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JBLP
06-03-2013, 04:27 AM
Dear All,
I'm Paul from the Netherlands and new on this forum.
I started a JBL 4344 DIY project and at the moment collecting the original drivers from The Netherlands, Germany and Austria. It is going well.
Next step is the cabinet.
I tried to find plans for it but cannot find them, so I did one myself. A copy of a front view picture in AutoCad. See drawing.

Now I like to ask enthusiast 4344 owners to help me with the measurements.
I will make a new drawing for the baffle (front panel) only.
What is the size of the front panel only (visible blue panel)?

Txs, Paul

Earl K
06-03-2013, 04:57 AM
Here are some links ( to a very slow server ) for large, detailed 4344 plans ( > 39M ) made by LHF member , ayaboh . ( Grab a coffee & wait .)

http://www.designcut.com/4344/4344-Final.pdf

http://www.designcut.com/4344/4344-Network.pdf

http://www.designcut.com/4344/Foilcals.zip

http://www.designcut.com/4344/Material-Layout.zip

:)

Odd
06-03-2013, 05:02 AM
I have drawings. Send a pm with your e-mail.
The file is too large for the forum.

JBLP
06-03-2013, 03:13 PM
Thanks Earl K and Odd; you referred to the same document.
It is a really well and detailed DIY plan for a JBL speaker.
But there is a but: he changed the design, the front look of the speaker.

He balanced the three drivers in one line and placed the 2405 next to the MH.
He also made the Foilcal bigger to match his 2405 frame. The two ducts are lowered.

I think I like to stay with the original design.
So with the information inside above mentioned document I can make the plan for the front view.
I will post the drawing soon.

JBLP
06-04-2013, 08:59 AM
This is the front view; combination of a scaled picture and the information in the document made by OS.
Can somebody confirm the measurements?
I do not have the size of the Foilcal and its position.
Thanks, Paul 59101

JBLP
06-04-2013, 09:10 AM
See difference original and design OS

59102

4313B
06-04-2013, 09:18 AM
The one on the right is the one to build.

The only thing I have to say with respect to the one on the left is "part it out". There are some good drivers to be had from that mess. :rotfl:

Odd
06-04-2013, 10:00 AM
Installing Drivers on line has clear advantages.

JBLP
06-04-2013, 03:30 PM
It looks like JBL initially put all the "big ones" down and in the middle. See 4343, 4344, 4345, 4350, 4355, ....

59127

The OS design does look good, but why is it changed? Is it only an aesthetic issue?

JBLP
06-15-2013, 04:11 PM
Made a circle jig today and tried it on a piece of plywood.
The center point goes under the router, so I can make small circles; the 2405-hole is only 79mm.
Waiting for the plates to make the cabinet.


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NickH
06-15-2013, 04:26 PM
Made a circle jig today and tried it on a piece of plywood.
The center point goes under the router, so I can make small circles; the 2405-hole is only 79mm.
Waiting for the plates to make the cabinet.


592265922759228

Hey Jblp,. Looks like a fun project your working on. Nice taste in tools too. I wish I could afford festool gear. Shoot I can't even afford a festool keychain:D.


Nick

JBLP
06-16-2013, 02:20 PM
Hey Nick.
Yes, it is fun. The sorting out, the making of the plan and actually working on it.
Taste of tools; if you choose JBL vintage, you have to choose for nice tools.......
Paul

NickH
06-16-2013, 06:58 PM
Hey Nick.
Yes, it is fun. The sorting out, the making of the plan and actually working on it.
Taste of tools; if you choose JBL vintage, you have to choose for nice tools.......
Paul

Don't get me wrong. If I could afford festool powertools I'd buy them. That would especially true if I did carpentry for a living. But I'm just a weekend warrior. Probably the most expensive brand of tools I have is porter cable. Jbl and festool are the same, the best of the best. And the best ain't cheap, lol.

Yes it is fun build your own loudspeakers. I love building things.

Good luck and keep us posted on your progress.

Nick

JBLP
06-22-2013, 03:41 PM
Got the material for the cabinet today, so the real work can start.

Again, good tools is half the work (Nick: not mine, borrowed!).


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NickH
06-23-2013, 06:58 AM
I have no problem borrowing tools, especially expensive ones. I don't own any machine tools. I use the ones I have access to at work. Makes life easier. My garage is not that big, lol. So your using mdf. I really like working with that stuff. Except for the dust. So fine it kills my allergies. But it is very easy to work with.

are you going to clamp and glue, use screws or what?

I use glue clamps and a pneumatic 18 gauge brad gun for most of my stuff. Except I did use confirmat screw on the side panels of my bass horns. Wanted the extra strength since they were huge.

I don't know if you can get it in Europe but I've had very good luck with a adhesive called pl Premium. Its made by loctite. It is like peanut butter and it expands when it cure making nice airtight seems. Its not quite as strong as pva but its way stronger then the wood its self.

looks like your one your way to having some fun. Keep us posted on your progress.

mech986
06-23-2013, 01:32 PM
This will be fun to follow!

JBLP
06-23-2013, 03:48 PM
My shed/garage. I have space, but it fills fast.....

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I'm using 30mm MDF Medite, the white milky glue, clamps and screws (5,0 x 60).
First secure the rectangle. Then clamp (binders) the top and bottom before drilling the holes for the screws.
Took the top and bottom one by one apart for the glue and bind it back before screwing.

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Keeps you off the street.....

JBLP
06-29-2013, 03:57 PM
Next step is making the base frame; makes the cabinets easier to handle/lift.
Made a sort of mould; one for cutting the 45 dr and one to glue the parts together.
I used 40mm furniture-plate / multiplex (left over from a solid door).

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JBLP
06-29-2013, 04:12 PM
Using the mould frame gives a nice joint (not that you will see it.....)

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The milky glue and screwed from the inside.

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I will not laminate the bottom with veneer, but just paint it black.

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NickH
06-29-2013, 05:26 PM
Making good progress. I like how you cut the miter joints on the base.

JBLP
07-01-2013, 02:06 PM
Making good progress. I like how you cut the miter joints on the base.

I'm using a handcircle saw to cut the 45 dr. Like this a mistake :banghead: (46dr or 47dr) will not be a problem.

JBLP
07-01-2013, 02:32 PM
Had to adjust the baffle a little (1 to 2 mm on two sides). Now it fits.

59344

Then, setting out the cut-outs. I'm still going for the original layout.
I'm also still looking for someone who can confirm the measurements. See post #5.
Also the foilcal. Txs.:bouncy:


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JBLP
07-05-2013, 05:25 AM
For the ports I can use a gray PVC sewage pipe: outside dia 110mm, wall th. 3.2mm and inside dia 103.6mm.
The 2235H specification sheet indicates a 160cm2 port; so 103.6 dia makes 84.25cm2 x 2 = 168.51cm2.
The length is indicated 28cm.
- What does it mean: "above mentioned port is tuning this enclosure to 30Hz"?

The 2122H will have his own enclosure inside the big enclosure.
This one is not having a port, although it will move some air.
- Why does this one not have a port; thus also not "tuned"?

:confused:

Odd
07-05-2013, 06:28 AM
Even if you try, you will not get the same volume as the original. The ports need to be adjusted after everything is installed.
Cut the pipes so they can be cut later.
Read about enclosuretuning here (http://www.google.com/#output=search&sclient=psy-ab&q=jbl+enclosure+information+manual&oq=jbl+enclosure+information+manu&gs_l=hp.1.0.33i21.2569.29881.0.33234.30.26.0.4.4.0 .160.2617.15j11.26.0....0...1c.1.19.psy-ab.4V2-lAoMwlo&pbx=1&bav=on.2,or.r_qf.&bvm=bv.48705608,d.bGE&fp=47e72f3278393839&biw=1280&bih=854)
2122 shall have a separate, closed box.

ratitifb
07-05-2013, 06:36 AM
The 2122H will have his own enclosure inside the big enclosure.
This one is not having a port, although it will move some air.For sure the 2122 will move some air and the closed box volume will act consequently like a spring, increasing the low resonant frequency of the system (adding stiffness of both elements, the driver and the closed box)

- Why does this one not have a port; thus also not "tuned"?
:confused:The port acts as a resonator and radiates its energy at low frequency above the resonant frequency of the driver. That is not necessary to tune the box when driven by a such speaker showing a low resonant frequency compared to the low cutoff frequency of the X-over band pass.

By the way, great craftmanship work you are doing and what a great project :applaud:

JBLP
07-07-2013, 02:58 PM
Hey guys,
Odd: So this will need to be tested when everything is in place. Did read the information, thanks.
Ratitifb: The network band pass is between 320 and 1300 Hz for the 2122. So the resonant frequency is below 320 and thus no port. Thanks.

Will start the cutouts soon......

JBLP
07-07-2013, 03:13 PM
This is what I collected so far:

5940659407

2235H are 100% (from Germany),
2123H to be reconed as 2122H (from Austria),
2425J + Beyma horn. Two different diaphragm's. (from the Netherlands),
2405H with not original JBL diaphragm's. Paint is in bad shape (from Germany).
Some work to do on them.

Odd
07-07-2013, 05:21 PM
Very nice work!

Refurbishment of 2405 info (http://www.audioheritage.org/vbulletin/showthread.php?30788-DIY-2405-refurb)

JBLP
07-08-2013, 03:51 PM
This is it; final layout. Did adjust a bit; more distance between 2235 and 2122.

5941459415

Thanks Odd; exactly what I have to do with my 2405's.
Some good tips from Wardsweb!

JBLP
07-16-2013, 04:26 AM
Next step, the cut outs, was nice to work on, they are on their way to become speakers......

59457

JBLP
07-16-2013, 04:27 AM
Cut outs ready.

59458

JBLP
07-16-2013, 04:10 PM
There is X-over 3133A for the JBL4333A for sale.
Can this be a good basis for a JBL4344 X-over by adjusting and adding some.....?

Fore sale:
59459

NickH
07-16-2013, 04:56 PM
Making good progress. You'll be listening to them in no time.

Are you going to put walnut veneer on the and paint the front baffle blue?

looks great so far.


Nick

Guido
07-16-2013, 11:09 PM
There is X-over 3133A for the JBL4333A for sale.
Can this be a good basis for a JBL4344 X-over by adjusting and adding some.....?

Fore sale:
59459

I recommend using charge coupled crossovers made with new components.

Congrats to this wonderful project!

JBLP
07-17-2013, 02:06 AM
Hey Nick,
Yes, I'd like to go all the way: veneer on the sides and top with the walnut front trim, black back and plinth and THE JBL blue baffle.
I found some discussions about the JBL blue....... didn't find the right one.
RAL 5007 is close but not the one and the Kenrick Sound guys in Japan make them too blue.
So, still investigating.

Hey Guido,
Thanks for reading and your recommendation.
The crossovers will be a project on its own.....

NickH
07-17-2013, 12:31 PM
Even though I don't own any jbl studio monitors, I really like that blue. I'll probably never buy any. But I'll definitely diy some 4350. I've always though they are the coolest speakers on the planet. But in also do the veneer and the blue paint. But I'd have to put a unique twist on them.

JBLP
07-20-2013, 03:43 PM
Bought the Mounting Kit for the 2235 on eBay from Duncs1946, CA, USA. Good stuff.

59485

JBLP
07-20-2013, 03:59 PM
I made a reservation for 1mm packing behind the 2405 and 2425 drivers.

59486

Next step will be the enclosure for the 2122; I'm thinking of something prefab.... tube?

Odd
07-23-2013, 02:25 PM
Enclosure for the 2122
You can use tube if you calculate the volume
See post 10 (http://www.audioheritage.org/vbulletin/showthread.php?314-4345-monitor-plans)

JBLP
07-23-2013, 03:57 PM
Thanks Odd. How do you know all these posts....??? You know your way.
Looks like there is a answer on every question inside this Forum.

Factory sizes of outside sewage pipes are 250, 315, 400,.... outside diameter.
315 can fit. SN8, class 34 is the most thick one: 315 - 9,2 wall - 296,6 inside diameter.
Post 10 (4345) has 14,3 ltr. The OS design cut has 15,5 ltr.
If I go for the 15,5 ltr then I will need 225mm inside length. 10mm in the baffle and 20mm for the cover makes two lengths of 255mm.
Lets find a road-paving-sewage contractor close by......

59498

Odd
07-23-2013, 05:23 PM
Thanks Odd. How do you know all these posts....??? You know your way.
Looks like there is a answer on every question inside this Forum.

Factory sizes of outside sewage pipes are 250, 315, 400,.... outside diameter.
315 can fit. SN8, class 34 is the most thick one: 315 - 9,2 wall - 296,6 inside diameter.
Post 10 (4345) has 14,3 ltr. The OS design cut has 15,5 ltr.
If I go for the 15,5 ltr then I will need 225mm inside length. 10mm in the baffle and 20mm for the cover makes two lengths of 255mm.
Lets find a road-paving-sewage contractor close by......

59498

Google is your friend.

Search, jbl 4345 dog house site:www.audioheritage.org (http://www.audioheritage.org)

Odd
07-24-2013, 02:14 AM
59500

ivica
07-24-2013, 09:23 AM
Thanks Odd. How do you know all these posts....??? You know your way. Looks like there is a answer on every question inside this Forum. Factory sizes of outside sewage pipes are 250, 315, 400,.... outside diameter. 315 can fit. SN8, class 34 is the most thick one: 315 - 9,2 wall - 296,6 inside diameter. Post 10 (4345) has 14,3 ltr. The OS design cut has 15,5 ltr. If I go for the 15,5 ltr then I will need 225mm inside length. 10mm in the baffle and 20mm for the cover makes two lengths of 255mm. Lets find a road-paving-sewage contractor close by...... 59498

Hi JBLP, 250 is fine, I have used

regards
ivica

just4kinks
07-24-2013, 12:36 PM
Factory sizes of outside sewage pipes are 250, 315, 400,.... outside diameter.
315 can fit. SN8, class 34 is the most thick one: 315 - 9,2 wall - 296,6 inside diameter.
Post 10 (4345) has 14,3 ltr. The OS design cut has 15,5 ltr.
If I go for the 15,5 ltr then I will need 225mm inside length. 10mm in the baffle and 20mm for the cover makes two lengths of 255mm.
Lets find a road-paving-sewage contractor close by......

59498

You're sure there will be enough room to fit your 2425?

Have you considered that you might want to upgrade later, to something bigger like a 2450 or 2441?

JBLP
07-24-2013, 03:40 PM
Got 60cm 315-pipe from a local contractor.
Re-used the 2235 baffle cut-out to make the cover for the enclosure (save the planet...)

Odd: like your graphics, what kind of program is it?
Thanks Ivica, but I think the 200 will be too close to the T-nuts of the 2122.
Just4kinks: it fits! I will post a photo with details. Thanks anyway.


5951059511

Too much pictures? :crying:

JBLP
07-24-2013, 03:53 PM
Just4kinks: I also was afraid for it, but it worked out well.....
Maybe I will support the 2425 from the cover of the 2122 enclosure.

5951259513

Odd
07-24-2013, 09:35 PM
WinISD from LinearTeam. It's free and come preloaded with most JBL drivers.

http://www.linearteam.dk/?pageid=winisd

ivica
07-25-2013, 03:31 AM
Just4kinks: I also was afraid for it, but it worked out well.....
Maybe I will support the 2425 from the cover of the 2122 enclosure.

5951259513

Hi JBLP,

Your work is absolutely gigantic, but I think that You have made one "mistake" not arrange the place for the future expansion from 2425 to 4-inch diaphragm driver as 2441-45-50 with 2311.

Regards
Ivica

badman
07-25-2013, 10:57 AM
Beautiful work and great job on the mid enclosure- but I'd add a separator if you can, dividing up the mid enclosure into two crescent shapes, rather than a tube, for as much of it as you can. If that's not feasible due to already having mounted it, any hard barrier you can do to break up the tube shape will be beneficial. Stuffing helps, a lot, but combine stuffing with a rigid barrier and you can really prevent enclosure resonances. I like how it's offset from the mid mounting, btw.

NickH
07-25-2013, 01:19 PM
Awesome.

JBLP
07-25-2013, 05:15 PM
Thanks all.
I got the idea from the L80T which I've been working on.
The mid also has a sort of tube-enclosure.
Badman: everything is mounted, cover is closed. You think stuffing is enough?

Some pictures of my L80T:

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Greg86z28
07-25-2013, 08:37 PM
Nice pictures.

It's always cool when someone does really nice work and can also snap really nice photos to show it off :thmbsup:

JBLP
07-28-2013, 04:15 PM
Hey Greg, photography is my other hobby, so when I'm making something I have to take pictures.

I like your collection.
I've a set L80T and L20T hocked up in my small office at home.
The sound is not bad.

59545

JBLP
07-28-2013, 04:49 PM
Fixing the fronts.

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JBLP
07-28-2013, 04:52 PM
Some more:

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JBLP
07-28-2013, 04:54 PM
I see I'm not a "Junior" anymore....:bouncy:

Amnes
07-31-2013, 02:35 PM
This thread is awesome!

NickH
07-31-2013, 04:15 PM
Hey jblp, looking good.

Your going to be listening to tunes in no time.

kind of off topic but that's a very nice drill press attachment. What brand is it? If I can even get it in the USA that is, lol

Keep up the good work.

Nick

JBLP
07-31-2013, 04:44 PM
Dziękuje Amnes.
I studied your "Large studio monitor clone take two" thread before. Impressive and nice result!
And! still a long way to go for me, especially when it comes to "what's under the hood"..... the V8.
I'm a little afraid for the crossover; I'm not an electro-technician.

Hey Nick,
It's a cheapo (20 euro) no brand Internet-ordered drill-attachement-something-tool.
BUT really handy; I'm always fighting with drilling perpendicular (the right word?).
Small minus: cannot be used with battery drill (no neck).

59585

NickH
07-31-2013, 08:13 PM
Yep that's the right word. I have 2 different ones. But I really like that it has the handle on the base. The return springs are a bonus too. Both of the ones I have attach to drills shaft. But I alway have trouble holding them in place.

It might be a cheap one but its well thought out.

Nick

JBLP
08-05-2013, 07:32 AM
The bracing took me two weeks.
I wanted to brace the baffle and the back panel in the middle (horizontal) and then connect them from with each other.
Rest of the bracing is a mix from the Design-Cut drawings and keeping the vents clear in the back.

59638

JBLP
08-05-2013, 07:39 AM
Bracing-2

59639

JBLP
08-05-2013, 07:45 AM
Bracing-3

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JBLP
08-05-2013, 07:57 AM
A bigger overview.

59641

JBLP
08-05-2013, 08:16 AM
Nick: Found the box; it has a brand and even made in Germany.
Maybe you can find it there.

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JBLP
08-18-2013, 03:56 PM
Found a way to support the 2425 on the back frame/panel.

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JBLP
08-18-2013, 04:10 PM
I thought it was better when the support is not touching the ML enclosure.

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NickH
08-22-2013, 09:32 PM
Jblp, stellar work as usual. Thanks for posting that info. I'll check the manufacturers site. See if I can get my hands on one here in the states.


I bet you can't wait to get them playing?

Looking good,
Nick

martin2395
08-23-2013, 12:17 AM
Hi JBLP,

Great work, especially the details!

One more pair 4344's in the Netherlands :cool:

JBLP
08-26-2013, 03:18 PM
I painted the inside with a wood primer to make the cabinet less sensitive to humidity.
The baffle is painted with a wood primer in color. It's blue, but for sure not :crying: the JBL one.
I'm still looking for the right JBL blue.

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JBLP
08-26-2013, 03:20 PM
5982859829598305983159832

Odd
08-27-2013, 12:05 AM
I have used BRILLANTBLAU RAL 5007 with good results.

Very nice job with the wood work!

Mr. Widget
08-27-2013, 07:17 AM
What a labor of love... very nice.
Most likely the most beautifully finished interior of any JBL extant... factory made or DIY!


Widget

georgebrooke
09-02-2013, 12:17 AM
What a great project... but very dangerous. I thought I had got all that refurbishment stuff out of my system, but I can feel the old enthusiasm starting again. I am really looking forward to to seeing the finished product. Best of luck with all the work still to be done. What you have done so far looks really excellent

George

martin2395
09-02-2013, 01:38 AM
Hi JBLP,

As I mentioned before (through PM?) It seems that the original JBL blue paint is impossible to match right.
The color will always bee too vivid/bright compared to the original.

Still, it looks good! Klasse! :thmbsup:

JBLP
09-02-2013, 04:15 PM
Thanks guys :bouncy:
Odd: you're always there with an answer. Thanks for following.
THE Mr Widget: thanks for your encouragement. I'd like to come back to you at the time I have to do the crossover.
George: don't give up the refurbishment, it's the best therapy...... Yes, still a lot to be done. No rush!!!
Hey Martin: I know, it will be a fight. I'd like to have a splinter of the original and send it to a paint shop to scan.

Stuffing inside, question:
Is it there, to absorb the inside produced sound and is it "the more absorption the better"?
I have some absorption material which they use in offices (interior) to kill the reverberation / echo / resonance.
It seems to have the highest absorption factor of all; a lot more than the glass wool.
Is this better to use?
Txs, Paul

NickH
09-04-2013, 06:17 PM
I'm seriously thinking about building a pare of these next. Though they won't look anywhere near as good as yours.

Keep up the good work. What to build me a pare next, lol.

ivica
09-05-2013, 12:26 AM
Thanks guys :bouncy:
.................
Stuffing inside, question:
Is it there, to absorb the inside produced sound and is it "the more absorption the better"?
I have some absorption material which they use in offices (interior) to kill the reverberation / echo / resonance.
It seems to have the highest absorption factor of all; a lot more than the glass wool.
Is this better to use?
Txs, Paul

Hi JBLP,

Wonderful work.
Too much absorption would reduce bass-reflex contribution to the frequency response, as the driver alone is almost not 'emitting' sound near box resonance frequency.
I think that the best would be almost not to absorb the frequencies under (say 50Hz), and the absorb all over, but such is not possible in the reality, as absorbing low frequency is very difficult job.
On the attached figure, there is idealized FR response, and the possibilities for standing waves, (depending on the dimensions especially where Lambd/2=one of the internal size, here it is assumed that Dim=0.6m = Lamda/2 ==> Fr=344/(2*Dim[m]) = 172/Dim[m]= 287Hz and its multiple...)

JBLP
09-08-2013, 02:57 PM
Hey Nick, always good to hear from you. Build them! I will support you (mental.....).

Thanks Ivica, I'm a building engineer, I can follow a lot..... but this one...... you have to help me.
Dim is content? 0.6m = 0.6m3?, 600 ltr?
Then what is Lamda?
Did you calculate standing waves for a 600 ltr cabinet with the outcome of 287 Hz?
Can I read from your figure how much to stuff the cabinet?

Building sample:
A lot of rooms have a acoustic problem; too long echo's.
To take action you have to measure the echo time in the room. A norm for offices is 1.0 seconds.
When you measure 1.7 sec, you can calculate how much m2 of acoustic absorption material you will have to place/hang to bring it back to 1.0 sec.
The m2 is also depending on the absorption specifications of the material you want to use.
Samples:
60025600246002660027

So:
Does something like that exists for loudspeaker cabinets?
How much absorption material to use? What figure / norm I have to aim for?
Txs, Paul

JBLP
09-08-2013, 03:18 PM
Fixing the 2425 support and preparing the back panels.

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JBLP
09-08-2013, 03:20 PM
6003660037600386003960040

Krunchy
09-09-2013, 02:06 PM
What a labor of love... very nice.
Most likely the most beautifully finished interior of any JBL extant... factory made or DIY!
Widget

I was thinking the same thing as I looked at the progression. Great Job!

NickH
09-09-2013, 05:10 PM
Jblp I don't think your in the diy realm. Your speakers look like there professionally made.

I can tell by your work, your very meticulous in your task. You've put a lot of thought into what's and his's of your build.

Once I finish my field coil conversion of my 2440's then I probably will attempt an altered version with 2" drivers.

I just have to have my frames coned and source 2 of the 10 inch drivers.

JBLP
09-23-2013, 02:20 PM
RAL5007 is an often suggested blue for the 43xx series, but ......
My feeling was that THE blue was somewhere in between the RAL5007, RAL5012 and RAL5015.
RAL5007 is too purple.
RAL5012 is too light but has this "vintage" tone.
RAL5015 is too blue.
So I started mixing and tried several proportions.

Please note that a digital camera is fighting to keep it real! When it sees too much blues it wants to correct it.
RAL5007 even looks more purple next to other blues.

60201602026020360204

Odd
09-23-2013, 02:38 PM
You should take into account that the blue face JBL monitors were in production for many years.
There are several varieties of blue on the original.

You must make a choice.

60210

JBLP
09-23-2013, 02:45 PM
Then I selected the 'best' three options;
- nr 4: 1/2-5007, 1/4-5012 and 1/4-5015,
- nr 5: 1/2-5007 and 1/2-5012,
- nr 7: 3/4-5007, 1/8-5012 and 1/8-5015.

I got closer but,
nr4 is still too blue,
nr5 is still too light and
nr7 is still too purple.

Too blue --> less 5015.
Too purple --> less 5007.
Too light --> less 5012.

I narrowed the triangle but had to go in between again: nr13: 0.6x5007, 0.3x5012 and 0.1x5015.

Of course this is debatable and disputable....... it is an effort and maybe the blue I like.......

6020560206602076020860209

JBLP
09-23-2013, 02:57 PM
Hey Odd.
I saw that picture before and I like that blue.
My nr13 is close; the digi camera made it more blue.
Your picture is with a lot of brown (wood) in it so there the blue is maybe more like it is in reality.

JBLP
09-29-2013, 02:43 PM
The cabinet is on going and have to start working on the drivers.

I have a set 2405H in bad cosmetic shape and with a not JBL diaphragm.
See pictures:

6024360244

JBLP
09-29-2013, 02:49 PM
I also have a set 2404's with JBL 2402 diaphragms.
The magnet looks really good and clean.

My question:
Can I use the 2404 magnet, the 2402 diaphragm and the 2405 alu finishings (after repainting) to get my 2405 set?


See pictures:

6024660247602486024960250

JBLP
10-20-2013, 03:13 PM
I'd like to cut the vents and put them in.
Used your LINEARTEAM.DK vent calculator.

I deducted all the bracings, the LF-enclosure and the drivers from the volume of the cabinet:



Cabinet









58,2
100
33,2
1
193224
193,22
liter



minus









3,14
219,9289
22,5

15537,98
15,54
liter



5,5
2,8
33,2
9
4601,52
4,60




5,5
2,8
47
2
1447,6
1,45




5
2,8
20,5
2
574
0,57




1,9
7
54
1
718,2
0,72




1,8
7,5
33,2
1
448,2
0,45




1,8
4,9
58,5
2
1031,94
1,03




2
1
100
2
400
0,40




2
1
58,5
3
351
0,35




2
1
69,5
2
278
0,28




2
1
33,2
4
265,6
0,27




2,8
2,5
60
1
420
0,42




2,8
2,5
53,5
1
374,5
0,37




drivers




7,50
(4344 Active Project)







33,95


















Total:
159,28
liter













LinearTeam.dk
159
liter








30
Hz








2
number of vents







10,36
dia vent








27,762
length vent






Odd: how accurate will this be? I still have to test later?
Thanks.

Strange: when I fill in 159 liter, 30 Hz, 1 vent, 5cm dia -----> Length is calculated to be 0.456cm....... So why to make two big vents?

JBLP
10-20-2013, 03:26 PM
6040760408604096041060411

Odd
10-21-2013, 12:37 AM
You're probably pretty close.

You can tune the cabinet once everything is installed.
One method is described here. (http://www.lansingheritage.org/html/jbl/plans/1979-manual.htm) Page 28

There are also other ways.

2235. Volume Displaced by Driver When Mounted in Enclosure: 6 L
Other drivers?

So why to make two big vents?

If they are too small you will get noise from the air that passes in the tube.

Stuffing

Use glass wool as original.
Glass wool increases the volume in the cabinet a bit.

martin2395
10-21-2013, 01:23 AM
These 2405H's are rough, but there is nothing that can't be fixed ;)
Someone from LH forums has posted a topic about refurbishment of two 2405 tweeters some time ago, take a look:
http://www.audioheritage.org/vbulletin/showthread.php?30788-DIY-2405-refurb/page2

I second the opinion to use glass woo, I've spoken to some JBL freaks in the past and all of them told me to use only glass wool.
However I'm asking myself if there is any way to put a dust/particle filter on the bass reflex pipes since glass wool is nasty stuff.

1audiohack
10-21-2013, 08:44 AM
However I'm asking myself if there is any way to put a dust/particle filter on the bass reflex pipes since glass wool is nasty stuff.

I see this concern voiced quite often. I have vintage and new JBL and a ton of pro boxes and have yet to ever notice that any of them have ejected fiberglass. Some of its pro gear that gets banged around and moved a lot. I don't know but it's something I stopped worrying about a long time ago.

Barry.

more10
10-21-2013, 01:52 PM
There is a Swedish thread, Allram moffar i lådan (http://www.faktiskt.se/modules.php?name=Forums&file=viewtopic&t=40658), where different damping materials are tested. Google translate will probably make it readable. Gullfiber = glass wool. Moff = slang for damping material.

Conclusions are: Glass wool is good for midrange, but not for bass. Wool and twaron are good for all frequencies.

Guido
10-21-2013, 02:05 PM
THAT sense for detail makes me speechless! :spchless:

This baffle blue research is simply amazing.

JBLP
10-28-2013, 03:48 PM
Thank guys.

Martin, I agree with the fact that glass wool is nasty stuff. I don’t want to use it in the house (sorry Barry).
Filled my L80T’s with sheep wool, which is nice to work with and with good results in the low tones.

More10, I (and my friend Google translator) checked the Swedish thread where they test the damping materials.
I like the way they do the test and included the IKEA bed.
What I miss is the starting point: What are you looking for and THEN try to find it. I still cannot find the 'goal', the 'aim' of the internal stuffing.
Is it to kill as much as possible sound inside the cabinet? And then only for the low frequencies; it's only the 2235 who makes sound inside the cabinet.
The Swedish test comes with wool and twaron to be GOOD...... for ??? damping.

Is glass wool maybe used because of the price?

I'd like to use this special (left over from a project) acoustic damping material which costs a fortune (with a reason). Not for me in this case......

In the meantime searching the web for "damping inside speakers".


Thanks Guido: if you do it, you better do your best.

JBLP
10-28-2013, 04:00 PM
6045960460604616046260463

NickH
10-28-2013, 07:53 PM
Nice. Your going to have some first rate speakers when done. Its a happy feeling listening to speakers you built yourself. Its like a drug.

pos
10-31-2013, 06:34 AM
looks better than new!

1audiohack
10-31-2013, 08:33 AM
Martin, I agree with the fact that glass wool is nasty stuff. I don’t want to use it in the house (sorry Barry).

No worries here! I just think people worry about a lot of things needlessly so I just wanted to share my experience with glass. But, I have a tritium powered exit sign in my bedroom and 10 pounds of mercury on my bench so,,, :)

The stuff I use comes from a company called CWSI and is lightly coated with something that resembles hair spray. If its not identical to what JBL uses its by far the closest thing I have found. The down side is that it only comes in a great big roll that has to come freight.

ivica
11-04-2013, 07:02 AM
I also have a set 2404's with JBL 2402 diaphragms.
The magnet looks really good and clean.

My question:
Can I use the 2404 magnet, the 2402 diaphragm and the 2405 alu finishings (after repainting) to get my 2405 set?



Hi JBLP,

sorry for too late answer: 0.6m means 60cm.
http://www.audioheritage.org/vbulletin/showthread.php?34471-DIY-JBL-4344-project&p=352504&viewfull=1#post352504

so for your box INTERNAL dimensions frequencies (and their multiple) around 172Hz, 295Hz and 530Hz can introduce internal standing waves.

some interesting about damping material can be seen :

http://www.faktiskt.se/modules.php?name=Forums&file=viewtopic&t=40658

As I can see from the figures you have 2405H (ferrite ) and 2404H magnets, so I think you can use 2404 magnets and 2405 Phase plug, but using D16R2402 diaphragm ( from 2402 drivers) would reduce 2405 frequency response ...

Regards
Ivica

kawasakitech
11-07-2013, 11:17 PM
Hi

Really like your detailed build, awesome quality
I always wanted a 4 way JBL system as well but after reading a couple of books by Philip Newell (1 with Keith Holland) about studio monitor design and studio design I contacted Philip via email and he recommended to stick with 2 way as it's much easier to deal with the phase shift in the system.
He explains it very well in his books.


:blink:

I have 2205s in 8 cu foot sealed cabinets with Altec Lansing 808-8As on 811B horns.
I use a DBX electronic crossover with a bi-amp and would recommend that you pursue that as opposed to a passive crossover.
Much cleaner sound with an electronic crossover.
Philip Newell also recommended the sealed 8 cu ft cabinet, I had it vented (both 4th order and equalized 6th order) at first but sealed is much cleaner, it is much easier to follow what the bass player and drummer are doing.
I was also using an SAE parametric equalizer but it deteriorates the sound quality.
Read Newell and you will get rid of all your Digital signal processing and EQ.
Your sound quality will improve.
I have ordered 2231s locally to try and get a bit more bass as I don't really need the efficiency of the 2205s.
I also purchased JBL 2425 drivers with 2370 horns to try to find out if the alnico/ceramic debate really means anything as well as the Ti/Al diaphragm thing.
I also have JBL 2447 drivers with an aftermarket horn to experiment with.
My plans are sand filled walls on the 8 cu ft bass cabinets and separate horn cabinets also filled with sand.
Wharfedale used a sand filled back on the early 60s W60 and it's way better damped (dead) than anything I've been able to construct using bracing, dead sheets, extra layers of wood etc.
If I turn up the volume the walls of the cabinet start to move caused by the sound off the back of the bass driver and it muddies up the sound.
(The advantage of a small cabinet I guess)
I just don't like the sound of modern speakers with a tiny bass driver and a dome tweeter, (no dynamics and they sound loud before they really are loud.
My system doesn't really sound loud until it's really loud, I just want more of what I have already.
"Too much is never enough"
My wife thinks I'm nuts but see if I care.:rockon1:
Maybe I'll post some pics as well.
BTW I'm from The Netherlands as well, Obdam in North Holland, moved to Canada in '03.
Good luck with your project and let us know what you drive it with and what it sounds like.
Thanks

Bloys Dekker

ivica
11-08-2013, 04:02 AM
Hi

Really like your detailed build, awesome quality
I always wanted a 4 way JBL system as well but after reading a couple of books by Philip Newell (1 with Keith Holland) about studio monitor design and studio design I contacted Philip via email and he recommended to stick with 2 way as it's much easier to deal with the phase shift in the system.
He explains it very well in his books.


:blink:

I have 2205s in 8 cu foot sealed cabinets with Altec Lansing 808-8As on 811B horns.

I have ordered 2231s locally to try and get a bit more bass as I don't really need the efficiency of the 2205s.
I also purchased JBL 2425 drivers with 2370 horns to try to find out if the alnico/ceramic debate really means anything as well as the Ti/Al diaphragm thing.

I also have JBL 2447 drivers with an aftermarket horn to experiment with.

My plans are sand filled walls on the 8 cu ft bass cabinets and separate horn cabinets also filled with sand.



Bloys Dekker

Hmm, with 2231A/H may be 2205 can be used as mid-bas, and some 811B "look-a-like" (bi-radial) horn but with 1.5" inch throat used with 2447 ( say at least with Radian 1245-J diaphragm),
and for sure a kid of UHF driver ( 2405, or may be 2402)...

regrds
ivica

JBLP
11-10-2013, 04:40 PM
Hey NickH: building them is also like a drug, what to do when they are finished.......
Pos: I was in Poland to visit a furniture-painting-factory and took them (2405 alu splits) with me. They did a nice job!
1audiohack: I'm stuffing them with the modern-lab-tested-sound-absorption-material and just see what it brings.
Ivica: So I will have to test them and see if there are standing waves. Take then the proper action?

Hoi Kawasakitech: what's number one on your list: Kawasaki or JBL? Your wive prefers JBL?
So you're really busy with a serious project: filling cabinet walls with sand.
I remember some audio freaks at the university testing concrete cabinets in the concrete lab. Talking about damping dead!

I will pursue your proposed crossover setup like this:
60558
Driving it with:
I'm infected with the Sansui Vintage virus. I will drive it with a CA/BA-2000 set and the bi-amp will be the AU-11000A.
I also still have my first S(on.)ansui AU-7900. A good and warm sound.

6055960560

So what system do you have now? Show us some of your projects.
Thanks Bloys; defend our cheese and tulips over there, cheese-head!

Mr. Widget
11-11-2013, 11:18 PM
I'm infected with the Sansui Vintage virus. I will drive it with a CA/BA-2000 set and the bi-amp will be the AU-11000A.
I also still have my first S(on.)ansui AU-7900. A good and warm sound.
As far as peculiar ailments go... it's not so bad.:bouncy:

Those are some beautiful pieces!


Widget

kawasakitech
11-13-2013, 11:56 PM
I think they go hand in hand.
My wife prefers motorbikes, she rides a lot better than I do but then she's 20 years younger as well.
Sometimes the student surpasses the master.
Go for a Sunday ride on a nice morning and listen to Rock and Roll later in the day or in the evening.
I actually fix motorcycles for a living but still enjoy riding and fettling my own as well.
Loudspeakers and audio/music is purely a hobby.
I try to get people that have put it all away back into it.
I've built loudspeakers for other people and only charged for materials as I find I learn with each project I do.
I build what I want not what they want.
If you never build anything you never learn anything.
Is concrete not a material that really rings?
I have always found that acoustically concrete houses (in The Netherlands) sounded terrible. (houses in Canada are wood frame)
2nd choice is brick with lime mortar much more dead than concrete or cement mortar. (Had an old house in Sint Maarten 1869)
New houses in Canada are lumber just like old ones but the wood is more like compressed toilet paper than real wood
The best acoustics are to be found in old wood frame houses where the wood is old growth and very heavy.
I have the DBX 223 2 way stereo electronic crossover as I mentioned
I use a Nottingham Analogue Space Deck or an older Pioneer PD-S502 CD player.
My vinyl takes priority as you can see but the CD player does work well.
I have a Croft Micro A tube pre amp and a Croft Series 5 power amp (28watts a side) for the horns.
I actually switched the 3B and the Croft and found they sounded the same.
I will need to repeat this experiment with the NAD.
I recently replaced a Sim Audio 4070 Celeste amp (borrowed) with a NAD 906 multi channel amp.
It is actually 3 stereo 30 watt/channel amps in 1 and I am using 1 channel to drive the 2205s.
I thought it would be great to experiment with bi/tri amp systems and at $150 pretty cheap.
The most transparent sound I've ever had if not the most super low bass.
I used to have a Bryston 3B but loaned it to a friend in Vernon. (He who owns the dead HH Scott)
I will have to try it again, I also have an HH Scott 150 watt Mosfet amp to try after I reassemble it with new caps etc.
I used to use 3 3B Brystons, 1 each bridged (400watts) for each bass drivers and 1 stereo for the horns.
I used to drive this to clipping regularly with no ill effects to the speakers that I can tell.
The NADs can also be bridged at 100Watts and I will try that as well.
I think that simple and small seems to offer more clarity than brute power.
I love your amps, they look like brand spanking new, where do you find stuff like that?
My first amp was a Sansui AU 2900, I used it on my Altec horns many years ago and found it harsh.
That was no doubt due to crossovers and levels etc, I'd love to try it again but don't know where it ended up.
A friend used to have a Luxman L80-V (40 watts a side) and I always liked that too.
I've always used Motorola piezos for super tweeters and found they work well regardless of what everybody says, remember to use a resistor to protect your power amp.
Lots of Dutch people here on Vancouver Island, our Honour will be protected.
As well as old world craftsmanship.
My Dad was a real "cheese head " from Alkmaar.
Thanks

Bloys

JBLP
11-17-2013, 03:32 PM
Mr Widget: a peculiar ailment one can grow old with.......

Hoi Bloys: thanks for sharing. I had to look on Internet for your amps and pre-amps to see what you mean: quite impressive gear!
Got my Sansui set from Germany, Ebay and picked it up from a smokers-house.
When I turned it on, nicotine smoke came out of the chimney......

So I took them apart to clean, polish and tip some black paint.
I had them re-capped by a professional.

60644

JBLP
11-17-2013, 03:55 PM
Went to Martin2395 this weekend. Met him on this Forum and lives only 35 km from me.
Lansing unites :)

Martin has a set JBL4343 (with 2235H's), so I had my first 43-series experience: amazing, amazing, amazing!!!
So open, clear, pure, defined and quiet. No big wave of sound attacking your ears.

I so hope I can reach this point with my adventure.......

But he also has some gear driving them!!!! Active crossover and Bi-amped. Woofer cable direct to driver terminals.
What a sound!

I bought the JBL 5235 Crossover, he had for sale, with modified cards: 300Hz/12dB.

With Martins permission some pictures:
606456064660647

Amnes
11-17-2013, 04:29 PM
Looks like a very listenable setup.

kawasakitech
11-17-2013, 08:33 PM
Thank you
Does look like it's very listenable.
Don't the plants rattle on the cabinets?:(
I remember when my ex in The Netherlands watered her (not mine) plants and flooded them and my vinyl records.
I nearly killed her over that.:crying:
I have a dedicated room now with plans for acoustic treatment and no plants:applaud:
Nice to meet someone with a shared passion so close to home.

martin2395
11-18-2013, 03:02 AM
Oh yeah, these look familiar, 4343A with 2235H, 2121, 2421B and 2405 :D
I'm using a BSS FDS360 x-over set to 300Hz/24dB, Krell 50mkII amp for the mid/high section and the K2 is powering the 2235H's.
Cables are (almost all) MIT - 330, 750S2, Digital ref. and two ZCordII's.

@kawasakitech
The plants were my own idea ;) The idea is to let them grow long enough to cover the sides of the cabinets and the flower pot itself.
I only forgot that this kind of plant has water dripping from the leaves when you water it regularly, I saw it just on time when I saw some water on the cover of the amp.
The cabs don't mind a bit of water since they are not vineered, only painted.
The flower pots are like 4-5kg each and there is a piece of cloth between it and the speaker so the only things that rattle are the windows ;)

@JBLP
The foto's turned out better than expected I must say! They look quite decent when resized.
Sadly a lot of people think when they see the 4343 is that these are some kind of PA speaker and the first question they ask is "How much do your neighbours hate you?" :D
At least until they hear a nice piece of jazz or blues they quickly realize how 'polite' these monsters actually can sound....

You Sansui gear looks lovely!

kawasakitech
11-19-2013, 12:05 AM
I bought a set of 2425s with 2370 horns and Ti diaphragms. $290 including shipping, very nice shape.:applaud:
Not sure if they are OEM JBL diaphragms, how can I tell?
They are 8 ohms as opposed to originally they were 16ohms (writing on back cover confirmed with a VOM)
The rear cover foams are bad but I've already found another thread on that.
Also the bolts to the horns and rear cover screws are plated steel (magnetic) my 2447s have stainless steel studs and screws.
Would it be better to replace these with stainless steel?
You can see I just laid them on top of the cabinets for a test, I unhooked the Altecs of course.
Very nice on first impression, listened to 4 sides of vinyl.(Genesis, The Police, Dire Straits and Lemolo):D
Not harsh at all but more efficient than the Altecs so they need to be turned down.
They actually sound like they have more clarity and less noise (turning the amp down always reduces noise with it).:o:
Just used cheesy speaker wire and normally horns sound better bolted to something on the flange as it damps out resonances.
Hopefully they will sound even better in the sand filled cabinets with respectable speaker wire, I usually prefer solid core as it is less harsh.
You can also see how I blocked the ports as opposed to the earlier pics.
You can also see the 2205 in place of the 2220 I had before.
I have no idea why I replaced the 2205s as I had them first but I did.
Would anybody have any ideas on how to get the Altec horns out of the cabinet without damage as i glued the flange with silicone, I thought it would damp resonance well.
It really sticks to both the wood and the aluminum casting.


JBLP
I like your cabinet bracing, mine is not as extensive but still extensive, I used tropical hardwood as Suzuki Motorcycles used to come in crates reinforced with really nice 2.5 cm square (1in) clear hardwood.
I built these cabinets in '85/'86 and got the hardwood at work for free.
Where did you get the design for the bracing?
Did you come up with it yourself or is it similar to OEM JBL?
Do you use any dead sheets or some such to damp panels further?
I have used thick roofing felt and tar adhesive along with ring nails for retention.
Does make a cabinet very heavy, but if you don't plan to move.:o:
Remember to let it all dry for a while before installing your drivers as adhesives can release solvents that soften the adhesives in your drivers.
I like your user name and gather JBL Paul but like the LP reference, do you have any vinyl?
Have you listened to your 2425/Beyma horns, I was wondering what you thought of them?
If I come to The Netherlands for a visit we should get together and spin some vinyl at least, if you're OK with that.6066260663606646066560662606636066460665


Martin2395
Does this refer to the JBL horn and acoustic lens?
Yours is a smaller version or am I wrong?

Mr. Widget
11-19-2013, 09:23 AM
Piezo tweeters... that takes me back. :D

On the question of impedance, you do understand the difference between AC impedance and DCR which a multi-meter will measure?

On horn removal, the throat of the horn will give you significant leverage. I bet if you unbolt the horn, you will be able to gently torque on the throat and get the front flange to pop free. If a gentle effort doesn't do the trick, take a single edged razor and slide it between the flange and cabinet, then try again. I no longer use silicone as a gasket but over the years I've glued dozens and dozens of drivers into cabinets and never had a problem removing them later.

Now about those horns... are you sure you want to go with that 2370 over the Altec? I'm not sure I would.


Widget

kawasakitech
11-20-2013, 02:43 PM
MR WIDGET

Thank you for the tips.
I'll give it a try, I hope the veneer does not delaminate from the front panel
Any experience with bathroom silicone solvent?
I do understand the difference between AC impedance and DC resistance.
I measured 6.6/6.7 ohms and I presumed the impedance to be 8 ohms and not 16.
I will listen a bit more before I decide which horns to use.:o:
I also listened to the JBLs crossed over at 1.2k and understand they are allowed to go lower.
I tried the Altecs at 800hz as opposed to 1.2k but that only works at very low level, as soon as I turn it up a bit it gets harsh.
Is it possible that the harsh sound people get from their Ti diaphragms is caused by a too low crossover point?:blink:
I will also try the Altec without the piezos as I listened to the JBL without as well.
I still want to get the Altecs out of the cabinets as I plan to put the horns in separate sand filled boxes to damp resonance.
I'm not as ambitious as JBLP but am proceeding with ongoing experiments over the long term.

Bloys

JBLP
11-20-2013, 04:31 PM
Hey Kawasakitech: See post 2 of this thread; Earl k and Odd gave me the plans for a 4344-DIY.
It's a very well detailed and well worked out plan. The author is OS (on the plans) but I still don't know who this is and thus to thank.
But as discussed after, the design of the front look was changed in these plans. I went back to the original layout of the factory made 4344.

I used this plan for a start (very helpful) but used my own guts-feeling for thickness mdf-sheets, bracing, supports, fixings, etc.
It was also depending on the wood I had on stock in my shed. Like you did: building with left overs and free materials is always nice (and green....).
The bracing is based on "it cannot be too strong", so I put more in. Same principle for the round sewage pipe (10mm thick) for the 2122 enclosure; I thought it would be stronger.
When I now knock with my knuckles on the enclosure, it sounds dead and solid.
So I think I don't have to use dead-sheets or other materials to damp the panels (30mm MDF-Medite).

I'm filling the cabinet now with special sound absorption material; high tech stuff. I'll see what it does.

User name: LP does not refer to vinyl. I don't have vinyl.....
My last name starts with a L, like James' last name and the P is indeed Paul.

Did not listen to the drivers since I don't have any crossovers. I have to start with them ...... as a NOT electrician......
I can start listening to the 2235H's with the JBL 5235 before the Amp.

Yes, visit, when you are back in cheese head land. No vinyl but for sure some good music. Hope the 4344's are finished and sound at least as good as Martin2395's JBL's.......

I'm so curious about your sand filled boxes, talking about NOT being ambitious...... :cheers:

JB LP

martin2395
11-20-2013, 05:31 PM
Cheese head land, nice one. I'd rather call it Cheesemouth country :applaud:

Paul, I still had a feeling that my BSS xover was doing something wrong with the signal, the cutoff frequency seemed too high to me.
I sent it to a guy from a Dutch DIY forum(he's also active member of LH) for a major check-up.
He sent me a graph showing that the crossover point was actually not 300Hz but around 350 and with veeeeeeeeery slow rolloff (certainly NOT 24dB/octave) actually allowing the woofer to play up to 2KHz, This may also clarify that strange room resonance I always experienced. :eek: Not to mention phase shifting...

Can't wait to hear it with new pots, op-amps and (partially)recapped and of course with the right crossover frequency since the components on the cards were wrong...

kawasakitech
11-20-2013, 06:20 PM
Mr Widget
What makes you say that you would choose the Altec over the JBL horns?

JBLP
I'm looking forward to listening at your place already, thanks for the invite, not very Canadian to kind of invite my self.:o:
I'll have to extend an invite for you and anybody else on this thread to listen to my efforts in Ladysmith BC Canada.
Contact me through this website please.
Too bad you don't have any vinyl, The Netherlands did have early and quite high levels of CD acceptance.
I did always get a lot of great vinyl deals on "Konninge Dag" (Queens Day) street markets when I lived there.:)

Martin2395
Interesting story on the crossover, how old is this unit?
Could be a lesson to us all to test equipment that we are relying on to be accurate and is possibly not.
Canadian cheese is crap, I do get some very old Gouda once in a while but it is very expensive as the duty on it is high.
It makes a great gift when visiting ex pats in Canada;)

martin2395
11-21-2013, 03:30 AM
@kawasakitech

My crossover is somewhere from the mid 90's so it's probably already 15-20 years old.
It was mostly the tech's fault who got the components on the frequency boards wrong, though.

JBLP
11-21-2013, 06:38 AM
Hey Martin; I like your Avatar! :rockon2:

Ruediger
11-21-2013, 01:47 PM
Piezo tweeters... that takes me back. :D ... Widget

Piezos require a crossover, because without an xover they sound harsh and they will break. The crystal will get cracks and will loose sensitivity. The impedance of a piezo speaker is a small capacitance. Putting an 8 Ohm resistor parallel to the piezo will turn it into an almost perfect 8 Ohm load.

Ruediger

Vahe Sahakian
11-21-2013, 07:12 PM
Martin has a set JBL4343 (with 2235H's), so I had my first 43-series experience: amazing, amazing, amazing!!!
So open, clear, pure, defined and quiet. No big wave of sound attacking your ears.



I have a DIY 4350, I am continuously amazed at the dynamic and super transparent sound of this vintage design, we are after all talking about 1970 technology but I would not trade this for anything else, although the design goes back to analog era I can not think of any speaker that can reproduce uncompressed digital recordings with such clarity and dynamics.

Good recordings sound spectacular on this monitor, crappy recordings sound horrible, I guess its garbage in garbage out design principle.

More recently I started searching for a smaller JBL’s for my second system, I have been searching for a pair of 4430’s for some years with no luck, but then one real clean pair became available in Houston so I packed a few CD’s and went for a demonstration, I had high hopes based on endless praise for these newer generation of two way JBL’s, but what a disappointment, I guess being used to the high frequency response of my 4350’s the 4430’s really sounded dull, the high frequencies were just not there, well had to give up on these after dreaming for these for over two years.
What exactly was JBL trying to accomplish with their newer 44xx series? Was this supposed to be an improvement over 43xx series? Not to my ears, not even close!

Vahe

Mannermusic
11-22-2013, 12:54 PM
I have a DIY 4350, I am continuously amazed at the dynamic and super transparent sound of this vintage design, we are after all talking about 1970 technology but I would not trade this for anything else, although the design goes back to analog era I can not think of any speaker that can reproduce uncompressed digital recordings with such clarity and dynamics.

Good recordings sound spectacular on this monitor, crappy recordings sound horrible, I guess its garbage in garbage out design principle.

More recently I started searching for a smaller JBL’s for my second system, I have been searching for a pair of 4430’s for some years with no luck, but then one real clean pair became available in Houston so I packed a few CD’s and went for a demonstration, I had high hopes based on endless praise for these newer generation of two way JBL’s, but what a disappointment, I guess being used to the high frequency response of my 4350’s the 4430’s really sounded dull, the high frequencies were just not there, well had to give up on these after dreaming for these for over two years.
What exactly was JBL trying to accomplish with their newer 44xx series? Was this supposed to be an improvement over 43xx series? Not to my ears, not even close!

Vahe

The bi-radial horns are designed to provide broader, more consistent "coverage" at the expense of the narrower, beamy high frequency flat output of the older exponential horns. They require significant equalization in the upper treble in order to achieve equivalent flat output response. Intended mainly for pro use. But, in terms of hi fi, they sound forced, dull . . . like you said! There is a technical paper somewhere in the data base here re the engineering development process. I experimented with a 2382A for about a year but never could make it "sound." Kind of like when you can't find the right trumpet mouthpiece. Come to think of it, never saw a brass instrument with a bi-radial bell. There is probably a message here! Mike:p

Mostlydiy
11-22-2013, 01:05 PM
I have a DIY 4350, I am continuously amazed at the dynamic and super transparent sound of this vintage design, we are after all talking about 1970 technology but I would not trade this for anything else, although the design goes back to analog era I can not think of any speaker that can reproduce uncompressed digital recordings with such clarity and dynamics.

Good recordings sound spectacular on this monitor, crappy recordings sound horrible, I guess its garbage in garbage out design principle.

More recently I started searching for a smaller JBL’s for my second system, I have been searching for a pair of 4430’s for some years with no luck, but then one real clean pair became available in Houston so I packed a few CD’s and went for a demonstration, I had high hopes based on endless praise for these newer generation of two way JBL’s, but what a disappointment, I guess being used to the high frequency response of my 4350’s the 4430’s really sounded dull, the high frequencies were just not there, well had to give up on these after dreaming for these for over two years.
What exactly was JBL trying to accomplish with their newer 44xx series? Was this supposed to be an improvement over 43xx series? Not to my ears, not even close!

Vahe

With the 4350 as reference Im not surprised that you found the 4430 lacking. The 2440 and 2405 are superb drivers and with the proper xo they work wonders. If you are more into vintage, you might like the L300 more than the 4430 for a smaller system.

/Mostly

JBLP
11-24-2013, 03:28 PM
Hey guys, thanks for reacting.
Vahe: post a picture of your DIY 4350, we like to see it.:bouncy:

Back to my 4344's.
I will bi-amp the low's and I'm thinking of keeping the passive x-over external so I don't have to open the 2235's everytime during the tests and fine-tuning of the x-overs.
So I bought 16 terminals, two pieces of high-voltage insulation board (10mm Pertinax) and made a layout. Right and left will be different.
Did a test cut-out with a 30mm piece mdf.

6071460715607166071760718

martin2395
11-24-2013, 05:33 PM
:D
Proper high-end project!
I will try to find that topic on LH where someone has built external passive networks for his 4344's!
As far as I remember he also had fancy wooden boxes for them.

Vahe Sahakian
11-29-2013, 11:35 AM
[QUOTE=JBLP;355440]Hey guys, thanks for reacting.
Vahe: post a picture of your DIY 4350, we like to see it.:bouncy:
Will try, not sure how to load images but let's see if it works

Vahe

JBLP
11-30-2013, 08:56 AM
Hey Vahe: Impressed by your serious DIY 4350, thanks for sharing.
All 4350A drivers what I can see. Did you also do the network?
So you changed the layout of the front. To fit the bookcase, or came the bookcase later?
I can imagine they sound like you described earlier.......:rockon1:

Thanks man!
Paul

martin2395
11-30-2013, 09:06 AM
Building your house around the speakers :p

Paul, do you know the model number of your Beyma horns? I hope to receive "2 2441 drivers soon as upgrade from the "1 2421B but I need the 2311 type horn which is much shorter. I can't find it anywhere in the Benelux so I wonder if Beyma has made a copy suitable for "2.

ds23man
11-30-2013, 11:02 AM
[QUOTE=JBLP;355440]Hey guys, thanks for reacting.
Vahe: post a picture of your DIY 4350, we like to see it.:bouncy:
Will try, not sure how to load images but let's see if it works

Vahe

Checked the picture several times this day, because something is wrong......

Now I know....:D

All the leads to the voice coils are pointing upwards..... :blink:

Mr. Widget
11-30-2013, 11:22 AM
[QUOTE=Vahe Sahakian;355641]

Checked the picture several times this day, because something is wrong......

Now I know....:D

All the leads to the voice coils are pointing upwards..... :blink:The beauty of the MA-15 woofer clamps is that you can rotate the woofers to prevent sagging. I used to go a few months with VC leads up and then a few with them down. I still would, but I don't have speakers with clamps. :(


Widget

Vahe Sahakian
11-30-2013, 01:16 PM
[QUOTE=Vahe Sahakian;355641]

Checked the picture several times this day, because something is wrong......

Now I know....:D

All the leads to the voice coils are pointing upwards..... :blink:

Those 2235’s were all recently re-coned with original JBL parts, I believe what you are seeing in that image is the image distortion caused by the wide angle camera lens. I re-examined all the cone drivers and everything is dead centered, there is absolutely no sagging.

Vahe

kawasakitech
12-01-2013, 12:32 PM
Vahe
Nice looking speakers, I bet you enjoy them.:rockon1:
What do you listen to?
What do you drive them with?
Widget is not suggesting that your drivers are sagging he is saying that he used to rotate his drivers regularly to prevent sagging which might happen if you left them in the same position for a long time.
My 2220s didn't sag in over 20 years but then they have a much lighter cone and stiffer suspension than the 2235s.
I would like to ask why you placed the horn/lens combo and the 2405s off to one side?
It looks like there is enough space in the cabinet to place everything in a vertical line, would that not produce a more stable stereo sound stage?
How does it sound with the speakers cabinets placed as they are in a bookshelf as opposed to further into the room?
JBLP/Martin2395
I was wondering why you used Beyma horns as opposed to JBL?:(
Would it not be better to keep it all JBL?:o:
I really like my new 2370s with the 2425s.:D
To me they are much cleaner than the my old Altec 808-8As/811Bs.
This is possibly the diaphragms, maybe I'll try the JBL diaphragms in the Altecs and vice versa.
Does anybody know if OEM Altec diaphragms are still available?
Where did you get this Pertinax?
I can only find it in 0.5mm thickness and think it would be too flexible.
Where did you get your binding posts?
Looking at your drawings it appears you have a drafting/engineering background.
My Dad did and always produced similar drawings of any project, he never made any speakers though.
I always try to as it helps precision but I have no training in those fields.

Mr. Widget
I had a machinist friend make polished aluminum clamps for me when I made my speakers.
If I make some more I will countersink the drivers flush with the front surface and will use simpler flat clamps.
Even steel could be used and fabricated with simple power tools, I prefer aluminum as it doesn't rust and rust is dangerous to speakers with open voice coils (most horns and all vented bass drivers).
Steel could be painted or powder coated though.
I prefer to just polish the aluminum.

I listened to Zooey Deschanel singing the Carpenters "Yesterday Once More" that I found on this forum. (nice voice but very poor background music and levels set too high for dynamic range of her voice)
Then I listened to Karen Carpenter singing it on vinyl on my JBLs and was really impressed with the performance and recording quality.
Both Karen and Richard were very good at what they did.
You might not like the Carpenters but will have to admit that very few recordings match that level of quality and professionalism.;)

Vahe Sahakian
12-01-2013, 01:35 PM
Nice looking speakers, I bet you enjoy them.:rockon1:
What do you listen to?
What do you drive them with?
Widget is not suggesting that your drivers are sagging he is saying that he used to rotate his drivers regularly to prevent sagging which might happen if you left them in the same position for a long time.
My 2220s didn't sag in over 20 years but then they have a much lighter cone and stiffer suspension than the 2235s.
I would like to ask why you placed the horn/lens combo and the 2405s off to one side?
It looks like there is enough space in the cabinet to place everything in a vertical line, would that not produce a more stable stereo sound stage?
How does it sound with the speakers cabinets placed as they are in a bookshelf as opposed to further into the room?



Since you asked;

First and foremost I did not care much for the horizontal setup of the originals, those are very difficult to position in home music room settings, JBL used the same horizontal ergonomics with the next generation 4435 and all the way up the their Everest. In all residential setups that I have seen with 4350/4355, 4434 or the Everest these monster sit low on the floor and that is the worst possible way to utilize these speakers, I consider a distance of about 2’ an absolute minimum from woofers to the floor.

Mine uses all stock components including 3107 networks, the active crossover is JBL 5234A, have two of those, one with 250Hz card and another with 290Hz card, I have tried both and can not really tell any difference. There was a discussion here on this website a while back on charge coupled crossovers for these speakers, I got on a little late, I did send an email to the person making these to see if I could buy a set, never got a reply from him.

As for why I did not place everything on a vertical line, that would increase the height too much, and given the size and volume of the music room I do not think that such arrangement would make much difference, in their present configuration the tops of the cabinet is 64” from the floor.
I will try to load another photo of the stereo cabinet photographed from my normal listening position which is roughly 12-14 feet from the JBL’s. You can pretty much see how large the space is and how tiny these JBL monsters appear in that space.

The “bookshelf” is in fact a 24” deep cabinet, it is 8’ high and 17’ wide. The cabinet was constructed to house all my stereo junk including the JBL’s, I did all the work all by myself, I am an architect by profession. This is my music room, it is isolated from the rest of the house, no TV in this room, strictly music.
The rest of the room has acoustic wall treatment, all the books and other items stacked up in the stereo cabinet help the room acoustics, there are no echoes from the walls and the sound stage is superb, you can “see” where each instrument is located.

These DIY’s were built a long time ago, I am primarily into classical and some jazz, 100% acoustic instruments, I have a large collection of LP’s, even larger collection of RBCD’s but now I am pretty much into SACD, well recorded SACD’s do sound noticeably superior to CD’s on a wideband equipment.

The enclosure is made of ¾” birch plywood, the two separate 5 cu ft. low frequency enclosures have an additional ¾” dense particleboard liners laminated to the outer birch plywood. Throwing a punch at the side of the low frequency enclosures feels like hitting concrete, no resonance issues with this enclosure.
The downside of this is the weight, if I had to do it over again I would make the low and high ends in totally separate boxes.

These 4350’s have definitely good many strengths and also many weaknesses.
For reproducing pipe organ at full power these are ideal speakers, they produce very powerful and natural sound all the way down to about 28 Hz totally free of subwoofer style unnatural booming bass. The high resolution solo piano recordings, particularly reproducing the sound of Steinway D is one of the strengths of this system.

I use two vintage McIntosh 2205 power amps and also a Mac preamp, my music room is large, 18’ x 27’ with sloped high ceiling, the volume is roughly 6000 cu. ft. 20W per channel for each hi-low ends is the upper limit for the volume from my listening position, about 12 to 14 feet from speakers, that I can tolerate, above that the volume becomes dangerously loud.

And, although the design dates back to analog era, the way these 4350’s handles uncompressed orchestral recordings on SACD with all of the dynamic range is something that very few speakers can handle.

The extreme clarity does have its negatives, 4350 has killed the vinyl for me, classical music unlike rock/pop does have frequent very quiet whisper like musical passages, this is where all the surface noise, clicks and pops and high level of audio distortion that is the hallmark of the vinyl starts competing with the music, for vinyl I recommend B&W speakers, I have a pair of two way B&W’s that I use for vinyl, they do a better job of masking surface noise than JBL’s.

Garbage in, garbage out pretty much describes the sound of these larger 43xx series JBL’s.

Vahe

kawasakitech
12-02-2013, 12:55 AM
Vahe
Thanks for all that.:)
The first pic is kind of deceptive, this brings it all into perspective.:D
I thought the cabinet is tall enough for all the drivers in a vertical line, they need to be lowered and brought closer together.
I was also under the impression that drivers work better at crossover point if they are closer together vertically.
Why should a bass driver be at least 2' from the floor? mine are much lower and seem to work pretty good to me.
I listen mostly to 60s and 70s Prog rock but also later stuff from The Police, Dire Straits The Floyd Marillion etc.
Pretty much all on vinyl.
Lots of open spaces in the stuff I listen to and I find my Nottingham Analogue is very quiet if the record is well taken care of.
It also sounds very clean and natural.
I still have Led Zeppelin II that I bought new back in the day and it sounds fine.
Vertical tracking height adjustment is very important for low noise.

Bloys

ivica
12-02-2013, 06:13 AM
Building your house around the speakers :p

Paul, do you know the model number of your Beyma horns? I hope to receive "2 2441 drivers soon as upgrade from the "1 2421B but I need the 2311 type horn which is much shorter. I can't find it anywhere in the Benelux so I wonder if Beyma has made a copy suitable for "2.

Hi martin2395

I think that SELENIUM HL14-50 would be very good replacement for 2311.
http://www.parts-express.com/selenium-hl14-50-2-exponential-horn-45x45-4-bolt--264-316
Its price about 25U$D
But a kind of lenses ( like 2308) would be welcome in order to to spread horizontal dispersion.

Regards
Ivica

martin2395
12-02-2013, 10:45 AM
Hello Ivica,

Thank you for the advice, I already have the 2308 lenses but it looks like that the Selenium horn would require drilling new holes in the cabinet.
I always try to avoid any modifications that affect the visual appearance of the speaker, I don't really care what sits inside but the outside must look 100% stock. :)

kawasakitech
12-02-2013, 12:54 PM
I remember seeing a documentary about sound/music once.
Everybody who was interviewed introduced themselves and then made their comment
Ray Charles gets as far as "R" hesitates and realizes everybody watching knows him anyway.
Then he goes on to say "I only care what it sounds like"
I know we all have different criteria but I think he's on to something;)

Bloys

JBLP
12-03-2013, 05:15 AM
Martin, see pictures for the Beyma horns. Cast Aluminum.

Kawasakitech, this is why I use them: The guy I bought the 2425J drivers from had these also for sale; 15 euro per pcs.
I think they are exactly the same as the 2307, only black.

I got the Pertinax from a plastic products company in Utrecht; in Holland also called HAPA, hard-papier. Or it's called Tufnol, Turboniet.
They have them in all thicknesses and sizes.
Binding posts are from an intenet-shop: too much choices, too different prices (from 2 euro to 160 euro per piece). I just used common sense....
I'm a building engineer, building-management. The spindle between client, architect, constructor, contractor, government and all the rules.
I don't have a drafting background but I have to check/control/change drawings and sometimes design, so bought a CAD-program and a book "how to.....". Life can be easy!

Vahe: What a nice music room and I like you did everything yourself. I also try to do everything myself, special carpentry work. And I'm also not allowing another working on my classic car.
I live in an old farm which I still have to renovate; combination of old wood trusses details and new black steel elements. Later!
But first my 4344 project and then design an interior around it.... priority list!


608036080460805

martin2395
12-03-2013, 05:43 AM
Thank you Paul, they look really well made! I'm gonna do a search to find out if they also made the short "2 version.

kawasakitech
12-06-2013, 12:30 AM
JBLP
What do you use as a drafting program.
Your drawings look very professional, and I wouldn't expect anything less from someone in your line of work.
All I could find was 3D sketch-up for drawing houses.:(
I need a simple 2D drafting program, any recommendations?
Thanks

Bloys

JBLP
12-07-2013, 04:52 PM
Hoi Kawasakitech.
It's AutoCad 2013. Not cheap if you have to buy it, got it from a friend. The book to learn basics was 2 euro.
I didn't reach the 3D chapter yet, but I will probably not get so far, 2D is enough for me.

I'm putting the 2405's together; will post the pictures soon.

60841

butlern
12-08-2013, 06:02 AM
Hello Chaps
i have been following this and other similar threads with interest. im busy with a project of a similar nature myself here in South Africa, involving, the purchase/ assembly of all the bits for a set of JBK 4344MK11's. i have most of the "expensive" bits now and require only the horns for the 275nd drivers, the crossovers and the foilcals. can anyone here perhaps assist with this?
i have the plans for the crossovers, but, dont have access to a reliable individual to build them. would also far rather buy the real thing if at all possible.

anyone able to help here?

regards
nigel






Martin, see pictures for the Beyma horns. Cast Aluminum.

Kawasakitech, this is why I use them: The guy I bought the 2425J drivers from had these also for sale; 15 euro per pcs.
I think they are exactly the same as the 2307, only black.

I got the Pertinax from a plastic products company in Utrecht; in Holland also called HAPA, hard-papier. Or it's called Tufnol, Turboniet.
They have them in all thicknesses and sizes.
Binding posts are from an intenet-shop: too much choices, too different prices (from 2 euro to 160 euro per piece). I just used common sense....
I'm a building engineer, building-management. The spindle between client, architect, constructor, contractor, government and all the rules.
I don't have a drafting background but I have to check/control/change drawings and sometimes design, so bought a CAD-program and a book "how to.....". Life can be easy!

Vahe: What a nice music room and I like you did everything yourself. I also try to do everything myself, special carpentry work. And I'm also not allowing another working on my classic car.
I live in an old farm which I still have to renovate; combination of old wood trusses details and new black steel elements. Later!
But first my 4344 project and then design an interior around it.... priority list!


608036080460805

kawasakitech
12-08-2013, 05:52 PM
JBLP
Do your 2405s use stainless steel hardware?
My 2447s do but my 2425s do not.
I don't know which were produced first.
The 2447s also have studs to mount to horns and the 2425s have ordinary bolts that you can buy at any hardware store, they didn't even have washers but I put some on.
I am wondering if this is a cost cutting measure by the product cheapening department (accountants/bean counters):(
Has any one experimented if this is audible and hence worthwhile to up grade.

Bloys

mech986
12-08-2013, 07:23 PM
JBLP
Do your 2405s use stainless steel hardware?
My 2447s do but my 2425s do not.
I don't know which were produced first.
The 2447s also have studs to mount to horns and the 2425s have ordinary bolts that you can buy at any hardware store, they didn't even have washers but I put some on.
I am wondering if this is a cost cutting measure by the product cheapening department (accountants/bean counters):(
Has any one experimented if this is audible and hence worthwhile to up grade.

Bloys

JBL used appropriate alloys, metals, and materials where it was appropriate. I'm not aware of stainless steel being used in the 2405 bolts but they are good quality flat head machine screws for the mounting plates, and a round head or pan head machine screw for the center diffuser mount. I'm not aware of any audible difference encountered by using any exotic hardware to mount the horns to the compression drivers. What is required is sufficiently strong hardware torqued with appropriate force to hold the driver to the horn. since the vast majority of compression drivers seem to hold pretty well (and sometimes with cradles to support the driver weight), JBL's choice of hardware seems ok to me.

JBLP
12-09-2013, 03:07 PM
Hey Kawasakitech.
No, no stainless steel items. I cleaned and polished all, so maybe that's why they look stainless (without stains.....).
The screws and rings are steel, the big square black painted rings and the visible black "split-parts" are aluminum.
The binding posts look like chromed or otherwise coated.

Thanks mech986; feeling the weight it indeed seems the appropriate materials.

JBLP
12-09-2013, 03:12 PM
Hey ds23man.
Another cheese-head. Thanks for viewing.
Does the Ds23 comes from Citroen? What's your JBL connection; any collection / DIY?
Paul

ds23man
12-10-2013, 10:15 AM
Hey ds23man.
Another cheese-head. Thanks for viewing.
Does the Ds23 comes from Citroen? What's your JBL connection; any collection / DIY?
Paul

Paul I do own a Citroen DS23ie Pallas.:D


I have been working in the pro audioscene as a sound engineer from 1985, mainly with JBL powered speakers.

My current home setup is a two active system with 2235H low and B&G RD-50 high, Hypex Ncore amps and Hypex DLCP digital xover.

JBLP
12-11-2013, 04:14 PM
Cut the holes in the back panel for the connection terminals.
The Pertinax board with the terminals will be fixed from the inside.
I like the terminals to be recessed, so the cabinet can be put on its back later.

60874608756087660877

JBLP
12-18-2013, 10:15 AM
Put the 2405's together with 2402 dia's; have to start with these.
When the final sound / frequency response is noticeable shortcoming, I have to score the right 2405 dia's.

60910

JBLP
01-08-2014, 04:33 PM
Fixed the terminals on the insulation board; ready to screw on the cabinet back panel (from the inside).
Progress is slowed down due to temperature and humidity in the shed/workshop. I put the cabinets in my house to wait for the better season :snore:

61108611096111061111

JBLP
01-08-2014, 04:35 PM
61112611136111461115

pos
01-09-2014, 02:44 AM
Hi Paul

Why not use 8 pole speakons (http://www.neutrik.com/en/speakon/nlt8fp-bag)? That would have been simpler and sturdier.
Nicely done anyway!

JBLP
01-09-2014, 03:09 AM
Hi Pos,
My thoughts were: I will be bi-amping the woofers, so to bring the cable back to the 8 pole Speakons is more of a hassle then just go from Amp-2 with speaker cables straight to the woofer terminals.
For the passive part I wanted to make a sort of plug & play system. Also when I'm not happy with the results of the passive network of one driver, I can just take it (one) out and alter.
I don't know if I will make (two times) three little boxes or one box for the passive crossover.
I'm not there yet.......

This one I like; very nicely made!!!!:

61117

JBLP
05-25-2014, 02:35 PM
No further progress :crying:

Too many projects!

- found old L80T's and another pair of cabinets,
- found a set S119, mint cabinets, broken tweeters,
- put a new kitchen in my house:

6225662257

JBLP
05-25-2014, 02:44 PM
These are the nice cabinets, need only oil:

62258

And this is the set I found on Internet; badly shape cabinets, glossy repainted. But good hardware.

62259622606226162262

JBLP
05-25-2014, 02:50 PM
These I also found on the Internet. Perfect mint cabinets, but only broken tweeters.

6226362264622656226662267

JBLP
05-25-2014, 03:12 PM
Not much good to be found on the Internet.

This guy is very negative:
http://www.thevintageknob.org/jbl-S119.html

BUT:
I think the cabinet is really special, original from 1974! It makes a nice piece of art in the living room.

SO:
My idea is to make them more JBL. It looks like the woofer is borrowed from another brand, the tweeters also don't indicate JBL.
I have a set woofers from the L3 and found in Germany replacement tweeter (same size as the "control one" monitors).
I can also use the network from the L3.

The "audio-database.com" indicates following:
A magnetic-shield design for the woofer and only low cut for the crossover.
What does this mean?

Steps:
- built in the L3 woofer; small adjustment with the router,
- built 4 replacement tweeters in. Don't know the Ohm. Originals are 2 Ohm and connected in series,
- built the L3 network in,
- the L3 has a bass vent. The S119 not. Do I have to put in the (tuned) bass vent?,
- built proper connectors on the back of the cabinet (don't like the bottom in the original),

Pictures of the S119 hardware:

6226862269622706227162272

JBLP
05-25-2014, 03:16 PM
Pictures of the L3 hardware and the replacement tweeter:

6227362274622756227662277

martin2395
05-25-2014, 04:20 PM
Hi Paul,

It's amazing to see S119's in such shape!
Sadly i think that I have to agree with the TVK guy, looking at the units and filters JBL used my guess is that they will probably sound mediocre at best.
The tweeters are most probably Audax TW010 with some variation of the mounting plate, also the woofer looks ok to me.

The L3 woofer will most probably won't fit due it's rectangular shaped chassis not to even mention the different size of the boxes, different crossover point, tuning :blah: ;)

Also, as you can see the old woofer has a kind of metal can around it's magnet - that is the magnetic shield.
With it you can place the speaker close to your TV without it causing interference like a purple glow on the screen for example, afaik it's only visible on CRT TV's.

The low-pass filter means that your tweeters will start playing at a certain frequency (in the S119 - at 3KHz) and will not have to reproduce the bass as that would destroy them very fast.

Btw, the japanese version of audio-database is called audio-heritage.jp and is still being updated with new info while the english one stopped in 2010.
http://audio-heritage.jp/JBL/speaker/s119.html

JBLP
05-26-2014, 02:24 PM
Hey Martin,

Thanks.
I can make the woofer fit, and if the crossover is better I will change it also.
Bas reflex can be made if necessary and calculated to tune it.
I feel it's worth the effort.

"Low cut only".
Yes, the low is cut for the tweeters. And normally, the high is cut for the woofers within the same speaker.
Don't they mean with "low cut only" that the low is cut for the tweeters and the full signal is send to the woofer? So no "high cut"!

andyprice44
09-20-2014, 08:46 PM
I just found this thread today. I read through the entire length of it. Very impressive work. Have you made any further progress on the 4344?

Andy

JBLP
09-26-2014, 09:01 AM
Hey Andy, thanks.
No progress!!! I had some distraction.
Got a 4688 from internet; big m...f.... and I'm repairing the drivers. the spiders where deformed (to hot?)
Got the spiders from reconekits.com. They are not for sale in the Netherlands, apparently no market.....
Here some pictures:
6323063231632326323363234

JBLP
09-26-2014, 09:04 AM
Picture:
63235

I like to make this one...... two and maybe mirror imaged:

63236

martin2395
09-26-2014, 10:10 AM
You are one mad engineer Paul :D Now I know where that nice TCB that I wanted to buy went to!
I almost contacted the seller but my mum said no ;)

JBLP
09-26-2014, 03:28 PM
Yep, that one!
Your mum is right; you will wake and shake the neighborhood when you drive it with your amplifier :eek:...........

martin2395
09-27-2014, 12:15 PM
It's not that bad, it's only does 2,5kW @ 4 Ohm bridge :applaud:

I saw that you cut off the surrounds, when you replace them use the with original, hard onesand not foam or you risk blowing the drivers in the TCB ;)

JBLP
09-27-2014, 03:42 PM
Hi Martin,
Oeps...

Please explain.
Don't know yet if they will go back in the TCB; like to make the B460.

63256

martin2395
09-28-2014, 02:45 AM
There is a difference between the depth of the voice coil winding, the 2245H has 24mm and 2240H has 19mm but I don't think it will affect the performance much.
The quasi-2245H will be less powerful because a 2245H will bottom out quicker than 2240 because it has softer suspension.
Though it should still move the walls if needed :D

Toro Italo
11-17-2014, 04:33 AM
Good morning everybody!

First of all, thank you very much for sharing very useful info and advices.

I'm considering bi-amping of my beloved diy JBL4344.

Using an electronic crossover, I could bypass the low-pass passive 2235 and connect directly to the bass section final amplifier.

But how would I modify the passive high-pass, the one dedicated to the 2122? I mean that with inserting an electronic crossover network, the 2122 would be filtered by both the active and passive crossovers. Could this create problems of phase rotation or other kind of problems?

I hope I was clear enough ... sorry for my little English.

Thanks to you all for the wonderful job and for the support.

Best regards from Italy,

Toro

Odd
11-17-2014, 09:46 AM
If you have the original 4344 there is a switch at the input terminal.
This switch removes the components in the filter that should not be there when you bi-amp.
4344 and 4345 have the same crossover.

Chas
11-17-2014, 10:37 AM
By the way, when you are doing the necessary surgery for bi-amping, you also have an opportunity to bi-wire above 290Hz. A pair for the 2122 with its associated network and then likewise for the HF/UHF combination, if you really want to guild the lily.