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clmrt
06-28-2005, 09:48 AM
A local pair came up for sale, I have dibs. She (!) is sending me pictures today. I have every intent to pick them up, to replace my L36's (:( ), and build custom cabinets to appease WAF. She also has other goodies, will advise in the FS forum if over my budget, to pass along info. I can ship if she can not....transmitters, subs, that's what I hear so far.

This may turn into my personal 4628 DIY cabinet thread, I hope!:applaud:

clmrt
06-28-2005, 10:05 AM
What kind of inputs are on a stock 4628? TRS? I'd like to bring my T-AMP along to test...Dunno if all drivers are working....:blink:

clmrt
06-28-2005, 10:08 AM
And if I do land them, I'll be on the lookout for the little suitcase model - 4612? To build up as a center...


"I laugh my evil laugh..."

- Sam Tellig

Zilch
06-28-2005, 10:34 AM
Yes, it's 1/4" phone jack speaker jacks. TS, actually, no "R." :D

Consider the Gold sound cabinet design.

http://www.goldsound.net/kit11.htm

If the Cabaret cabinets are in good shape, I want 'em. :p

4612B gonna make nice center - same drivers.....

clmrt
06-28-2005, 10:55 AM
The other items included a 2-way Samson powered PA job, and a powered mixer. MSP craigslist if anyone cares. Sorry about the OT.


Goldsound looks great!

Jinxing myself, I can feel it.:biting:

Zilch
06-28-2005, 11:05 AM
Goldsound looks great!It's a little "broad" at the top, is all. Doin' my own, I'd make the face trapezoidal. :p

[Goldsound gives the basics, tho....]

clmrt
06-28-2005, 11:08 AM
I emailed him for crossover costs, if they can be adapted to the K145 if deemed necessary. Just thinking they might be better than OEM? Maybe not, I know you like them as is.


I am no EE.

Zilch
06-28-2005, 11:17 AM
There's little doubt they could be improved with an engineered crossover.

The main problem with the stock boxes (other than WAF) is that they're not mirror-imaged. Drivers vertical in-line like the Goldsound would be an improvement, as well.

If you get 'em, we'll do more. RobH and others will have some ideas about cabinets and crossovers for us, as well, hopefully. :)

[Gonna want a separate sub, but that's fun too.... :bouncy: ]

clmrt
06-28-2005, 11:32 AM
I have an SVS-based DIY, 90L. Thumps pretty well to about 25hz. However, I have room for, say, 12cf as an end-table......hooooo boy.

Gettin ahead of myself.

1. Get the Cabaret's.
2. Make sure they friggin work.
3. Listen for a while
4. No regrets.....?

See you in the morning.

clmrt
06-28-2005, 06:53 PM
1.:D
2. One tweeter shows no Ohms, no sound. Bass drivers are E145, not K like I expected. Ferrite, not Alnico then, right? Cabs are typical used looking, not bad. All corners are there.
3. Listened to one in Mono. Bass shy, but dropping the pot nearly 75% and it came together OK.
4. .........

So, I think I'll see what new XO's would cost (JBL sourced or contract built), or wait for Goldsound's XO quote, if he provides it. Plus a new driver / phram.

Zilch
06-29-2005, 01:14 AM
1. :D

2. E145 is correct. Stock 2404 in those is "H-1," having 2402 diaphragm. Replacement is 2405 version. See Widget's ring radiator tests for the performance difference:

http://audioheritage.org/vbulletin/showthread.php?t=6368&page=1&p=60873

If you're switching to 2405, the recommended replacement, you'll want to change them both. Otherwise, PM me your address, and I'll send you a used (but good) 2402 diaphragm to install and get you running in stereo.

3. Try with sub, like you plan. Gettin' both running in stereo will boost the bass some also.

4. .....

Don't know what XO I'd recommend other than stock at this point, what you have. Maybe others will have some ideas....

clmrt
06-29-2005, 07:24 AM
:bouncy: ....ow, my back!:biting:

clmrt
06-29-2005, 07:28 AM
The wife FLIPPED OUT and started a whole "You're sick and you need help" thing.


:blah:

OT -

I also have like 6 bikes in the garage, as I am an avid mech. Can't ride much...no time for it. SHe hates looking at the garage, and now the basement. It's all hidden in the furnace area anyway, under drop cloths so it's all really neatly stored.

Oh well.

On T -

Thanks for the offer Mr. Zilch. PM on the way.

clmrt
06-29-2005, 07:32 AM
Dusty drivers...Damp cloth and wipe gently?

edgewound
06-29-2005, 07:51 AM
Use a paint brush and a vacuum to clean the dust off...not a good idea to get the cones damp. Yeah....wipe off the baby butt cheeks (2404H-1) with a damp cloth. Windex works fine too.

I love the 4628B....the Cabaret Series, I think, was some of the greatest speaker systems JBL ever made. The E145 is a KILLER LF driver. 35-20KHz. Very useful playback speaker...esp when cranked with plenty of clean power...say 300
-400wpc

Nice acquisition:applaud:

Edgewound

clmrt
06-29-2005, 08:25 AM
Keep eyes open for decent AVR with pre-outs.:blink:

Zilch
06-29-2005, 02:11 PM
The wife FLIPPED OUT and started a whole "You're sick and you need help" thing.Yeah, well, show her this thread:

http://audioheritage.org/vbulletin/showthread.php?t=6379

And tell here you're coming here for "therapy" at LEAST once a day.... :D


Dr. Zilch

Zilch
06-29-2005, 11:08 PM
This, maybe?

[Variation on a theme.... ;) ]

clmrt
06-30-2005, 06:01 AM
Sayyyyyy.....looks killer. Almost Sony-like, if you know which model I mean. I like how you incorporated the tilt back. I like that aspect a lot. Time-alignment or asthetic?


Magnetic grille attacher thingies...I have the perfect magnets for that.

Time to buy a table saw, unless I can figger out how to do it with a circular.:o:

clmrt
06-30-2005, 06:03 AM
Therapy - yeah. Where's my Methedone??????:barf:

Zilch
06-30-2005, 11:12 AM
Sayyyyyy.....looks killer. Almost Sony-like, if you know which model I mean.Actually, forum member Pangea's work inspired this design. Lemme see if any of it is still up here....

Alas, he deleted his early design exercises, apparently. :(


I like how you incorporated the tilt back. I like that aspect a lot. Time-alignment or asthetic?All that, but mostly, so's they don't play to yer knees. :p

Key to this design is that it's got big volume at the bottom (over 2 sqft. area inside), but, because of the angles and tapers, it doesn't appear massive, an important WAF element.

Even after deducting internal enclosure of the 2118, net internal volume is probably over 4 cuft., about the same as 4628B. It's an exercise in trig for you to calculate the actual internal volume.


Time to buy a table saw, unless I can figger out how to do it with a circular.http://audioheritage.org/vbulletin/images/smilies/redface.gifSkill saw ain't gonna get it. Trust me on this.... :D

clmrt
06-30-2005, 11:14 AM
Trig...trig...Oh - yeah, I remember now.

I'm farming out the plans to local woodworkers, to see if anyone wants a few $$ to try it out.

Think the Vas is 427 on the 145? Seems there's a thread about how JBL's spec sheet might be SNAFU'd.

Otherwise I'll stick with the original cab design, but I like to play with tuning points.

Zilch
06-30-2005, 11:20 AM
Make one outta cardboard first to get the "feel" of it. Fill with plastic peanuts to determine the actual volume. :p

johnaec
06-30-2005, 11:29 AM
Hey Zilch - I'll try to get that 3D stuff out this weekend...

John

Zilch
06-30-2005, 11:32 AM
Thanks, John!

I'll send you a .dwg file on this one, also. :applaud:

Heh, heh.

John's got some 4628B's what could use nice boxes.

[And he knows how to build 'em, too! ;) ]

clmrt
06-30-2005, 11:45 AM
If ya wanna get scary - -


I have an email buddy (member, too, or just a lurker maybe?) who has GRANITE - enough to build the plans, he says. He can cut the stock, and he has a contact that can polish and bevel the finished edges....and he's 5 miles away.

400# 4628's, anyone?

clmrt
07-02-2005, 11:42 AM
Thanks Z!

:applaud:

I see what you mean about foil-like leads. I don't have a solder sucker, but I'm good with an iron.

The little JBL warning you included intimidates me a bit, about how this is non-self-centering. I haven't taken the driver apart yet because all my Allen's are straight - gotta pick up some tools - so I have yet to see how it all goes together.

I'll search up some tips and tricks in the meantime.

Zilch
07-02-2005, 12:03 PM
I forget. There may be pins in there. You might take some pics when you do it to show others here how it comes apart, and what's inside. That probably warrants a separate thread under "Technical."

Seems to me it's been documented here before, but I'm not finding it. Give it a definitive title for future reference, like: "Ring radiator diaphragm replacement." Lots of members have experience with this, and will hopefully jump in with their tips.

Mr. Widget and I did mine. His tip was to tighten the center cone (phase plug) only semi-tight after installing the diaphragm, just enough to clamp it, while doing the sweep and listening for buzzes and rubs. Then tighten fully, holding the cone firmly so it doesn't rotate and wrinkle the diaphragm, and give it a final test.

I also found some posts regarding polarity. The terminal with the black dot connects to the black terminal post. (If the dot was red, it, too, would go to the black post.... :banghead: )

I'd say the warranty is pretty much void on that particular one, anyways, since it's dated 1996.... :)

johnaec
07-02-2005, 10:04 PM
OK - here's a quick version of Zilch's modified trapezoid design for the 4628B components. The cabinet volume might be slightly less than optimal for the E145, but a little judicious EQ ought to take care of that.

John

Zilch
07-02-2005, 10:33 PM
WOO-HOO, John. Like clmrt said, "Killer!"

Thank you again for doing the 3-D renderings.

I hadda bunch of Sony Style magazines here with the similar model cabinet he's referring to in them. Can't find 'em now, tho, of course. I think it was part of the ES line....

We gotta build some of these. :D

I'll do cardboard tomorrow.

[After I install the new dishwasher.... :p ]

Zilch
07-03-2005, 09:07 PM
O.K., O.K., how many packing peanuts fill a Z2 cabinet?

[I'll count 'em real soon now.... :p ]

Same height as L200, basically.

Once I know the volume, I'll cut in the other drivers and ports.

Looks like it came outta Tut's tomb.

[Or offa the back of legal tender....]

johnaec
07-03-2005, 09:54 PM
O.K., O.K., how many packing peanuts fill a Z2 cabinet?So what do you do - measure the displacement of a peanut, then count the peanuts? What if they're different sizes?? :p

I had another idea - use something like a 2235 and instead of the 2404H use an 035Ti. With the right crossover that would be pretty slick, and also have enough LF to preclude the use of a sub. Oh, but to have the time and drivers to play...

I also thought about using the L100T components in a similar, somewhat smaller cabinet. It'd look good with the grilles on, but without them, wouldn't have that smooth progression in driver size. I may still do something like that. I've got all the spare components, (incl. L100T3 x-overs), except for the 2214's.

John

Zilch
07-03-2005, 10:10 PM
I've got two pair of 4628B's here, one of 'em in stock cabs that UPS busted up pretty bad that I could dismantle and rebuild in mirror image, which'd be an improvement.

But, vertical in-line might be better, even with the stock crossovers. It's a driver combination that seems to work especially well. Gonna try it.

Even Everest, which also used rebadged 145's, had an optional sub. It's a trade-off to get what that driver is good at.

LE14x would likely play nicely here too, tho.

[Subs are NOT a problem.... :p ]

Zilch
07-04-2005, 02:56 PM
Apparent L250 derivatives, Sony's ES series SS-M3 two-way and SS-M7 and M9 three-way systems, cited above. 1996 MSRP $900, $1400, and $3500, presumably per pair, they featured 24 dB/octave crossovers, 8" woofers (M3 is 6-1/2"), "anhedral trapezoid" time-aligned cabinet design, 1" MDF construction:

{*burp*} :p

Zilch
07-04-2005, 06:28 PM
Gross internal volume of Z2 box for 4628B components is 3.85 cuft. with 1" thick front baffle and 3/4" sides, back and bottom. Increase depth 1" to 18" (top becomes 14.75" deep) for 4.2 cuft. volume, if desired. "Can" for 2118 will use 0.17 cuft. of gross.

Front baffle of loaded cabinet is 99-44/100% "business."

(Don't be askin' how it sounds, tho.... :p)

John's rendering was "Spot ON!"

Decorative bezels on both woofer and mid-driver consume panel space. We'll likely move them up a bit to make more room for ports in the bottom corners.

Grille minimum 1" deep will be required to clear both butt cheeks and E145.

Special thanks to the Makita "Barbie" saw for assistance in completing this prototype.... :applaud:

johnaec
07-04-2005, 07:57 PM
Zilch - looking at your mock-up I realized I made a mistake in my version! I noticed the vertical speaker clearance difference between yours and mine and realized I mistakenly made my main cabinet 36" high, plus the 1.5" for the base, resulting in a total height of 37.5". :banghead: 'Sorry! It would make it easier to fit the ports, though. And I still like your design better than the Sony, including the base treatment. Also, I get a little closer to 1.25" required for 2404H clearance.

I'm seriously thinking of a cabinet like that but with an LE14A, 104H-2, and 035Ti, with L100T3 crossovers, simply because I've got all those as basically extra components. I'm not sure how that crossover would work with the LE14A, though, as the LF portion has multiple components for the 2214H, not just a simple roll-off...

John

Zilch
07-04-2005, 08:15 PM
And I still like your design better than the Sony, including the base treatment.Yeah, it takes on a different "character" once it's loaded. Z1 became an entirely different object once the grille was added, too. I'm pretty happy with both now, actually.

No doubt some think them the ugliest damn things they've ever seen. That's how I feel about L250 et.seq.. ;)

For added WAF, we COULD make these do the vacuuming as well, I suppose....



It would make it easier to fit the ports, though.The error is fortuitous. I don't want to push the drivers any closer together; it needs a little more height, and perhaps more rake, as well. The tweeter axis is at 30" right now. I'll alter the dimensions accordingly. We'll get a bit more volume at the same time....



I'm not sure how that crossover would work with the LE14A, though, as the LF portion has multiple components for the 2214H, not just a simple roll-off....Build 'em. We'll tweak them into submission! :p

Come by and have a look. It's quite stunningly deceptive, actually. Silly, I stare at the pictures; the real thing is right here....

clmrt
07-05-2005, 05:42 AM
:applaud: Thou dost rock.

Robh3606
07-05-2005, 07:17 AM
"The cabinet volume might be slightly less than optimal for the E145, but a little judicious EQ ought to take care of that."

That is a nice looking speaker!! As far as EQ you can't EQ what's not there. You have to have a useable response to work with for the EQ to work. If you look at an E-145 in about 4 cubic ft. they rool off at around 70Hz. By the time you get to 40Hz you are way down and at 30Hz you are in the mud. If you want good solid bass below what room gain will add your going to need a sub to get there.

Rob:)

johnaec
07-05-2005, 07:56 AM
If you look at an E-145 in about 4 cubic ft. they rool off at around 70Hz. By the time you get to 40Hz you are way down and at 30Hz you are in the mud.Hence my idea of using an LE14A instead. 'Biggest problem is then level matching, at least if using the rest of the 4628B components...

John

clmrt
07-05-2005, 07:59 AM
Is 4ft optimum for the 145? I messed, and 6 ft tuned to 50 looked better.


Is that legal?:D

Space = no worries for me, I have room for 8 ft3...lemme see what that does...

clmrt
07-05-2005, 08:03 AM
8 ft3 tuned to 35 = -3 @ 36

What's the consensus on the curve going down-up-down?


(I know this is 2x the size of the prototype.....yipes!):blink:

Robh3606
07-05-2005, 09:40 AM
Is 4ft optimum for the 145? I messed, and 6 ft tuned to 50 looked better.


Is that legal?:D

Space = no worries for me, I have room for 8 ft3...lemme see what that does...

8 ft3 tuned to 35 = -3 @ 36

What's the consensus on the curve going down-up-down?


(I know this is 2x the size of the prototype.....yipes!):blink:

What value are you using for Vas?? There is a mistake in the JBL T/S table. When you run it in BBP6 it recalculates the Vas to 427L. When you make that adjustment and re-run the curves the difference is significant.


"So that means the Vas of the E145 is 427.7 liters instead of the published 274.7 liters. It makes sense since JBL likes to put this driver in a 4.0 cubic foot volume tuned to 40 Hz."

Last edited by Giskard : 06-22-2003 at 10:06 PM.



Check out this thread

http://www.audioheritage.org/vbulletin/showthread.php?t=361&page=1&pp=15&highlight=E-145


"Hence my idea of using an LE14A instead. 'Biggest problem is then level matching, at least if using the rest of the 4628B components..."

Hello John

That's the cobo I use in my mains. Le-14A's with E-145's up top. I really like the combination of these two drivers. I think the compliment each other well and blend nicely too. I use a active crossover an M552 to drive the plate amps for the Le-14'S and an M553 for the active crossover for the rest of the drivers. I tried using the rolloff from the E-145's and the crossover in the plate amp but the slopes were not steep enough to work well in my room. If you go with the Le-14 watch the x-max on them. I have mine tunned to 30Hz or so in 4 cubic ft. and the X-max peak is about 50Hz or so. I use that as a crossover point cause it works well in my room and it gives me 6dB of attenuation with the 24dB L/R slopes so it helps keep me from overdriving them. Don't know what you spacing will be but mine are close and couple below 40Hz so I get a rise in response which helps match them up efficency wise.

http://www.audioheritage.org/vbulletin/showthread.php?t=5896&highlight=coupling

You can also tailor the tunning on the boxes so the you don't have an abrupt change in the group delay at crossover. My 145's are in 5 cubic ft. and the GD at the crossover point is very close with Le-14's in 4.

Rob:)

clmrt
07-05-2005, 10:18 AM
:thmbsup: I was aware of the TS error and have it changed in my WinISD ProAlpha. Not a subtle difference.

Zilch
07-05-2005, 11:22 AM
I played briefly with E145 in WinISD and concluded there's not much to be done with that driver at the low end. Raising the volume, even substantially, has little effect.

BUT, it's also acknowledged that E145 is unique among bass drivers in other respects. I don't know what all of those are in detail, but I DO know I certainly like the way it plays in 4628B, and my objective here is to repackage those, and it looks like anything between 3 and 5 cuft. will be fine. It's no coincidence that JBL puts most of its 15's in 4 - 4.5 cuft. boxes.

It was a given from the start that these'd require subs. I have a pair of Citation 7.4's with LE14's in them, which Rob is telling us will play nicely with these. I'm presently playing the 4628B's with Sub1500's, and that combo will knock the house down with bass dynamics. Perhaps some restraint is in order. :p

Of course, a box is a box, and we can put whatever else might be appropriate in this design. We have about 4 cuft. to work with in these cool little things. The only woofer they won't accept in this size is an 18".

Y'all KNOW I'm not above putting like, LE14H-3's or others in these. Whatever perceived weaknesses LE14's have in the midrange can likely be mitigated through proper integration with the 2118's, themselves well recognized as excellent midrange performers.

Zilch
07-05-2005, 11:48 AM
Is 4ft optimum for the 145?WinISD says optimally flat tuning for E145 is 2.0 cuft. tuned to 57.10 Hz, actually. It's using Vas= 274.7. :p

With Vas= 427, is says same tuning in 3.109 cuft.

You guys building Everests: What's the volume and tuning used for E145 in those, please?

grumpy
07-05-2005, 03:26 PM
http://www.lansingheritage.org/images/jbl/specs/home-speakers/1985-everest/page10.jpg

looking at the tuning (dip & peak spacing), + history pages info, I get agreement with 8ft^3
and ~36Hz ... note that if you include some eq at ~250Hz, the curve flattens quite nicely
(eyeballed at -3dB, Q=.5), which is also present in the crossover. Should check this
with the nice dimensions others have sweated over + port depth & dia...

grumpy

Zilch
07-06-2005, 11:29 AM
Side view. I did that bend with a single kerf on the inside. Barbie Saw blade width is only 1/16", but that was enough in this 5/16" thick double-wall cardboard.

The angle is quite shallow, so same techinique may work on MDF or plywood. Slather the kerf with structural adhesive before bending to avoid having to make an actual joint there.

This view, and seeing the object itself, tells me it can easily afford to be deeper:

Zilch
07-06-2005, 05:32 PM
O.K., revised dimensions. Increased depth 1", kept the height the same, increased rake to 7. Each inch of increased depth adds approx. 0.3 cuft, now.

With 8" dia. Sonotube can for 2118H, building with 1" front baffle and 3/4" everywhere else, this should net just about 4.0 cuft.

Dual 3" ports are short. WinISD says 3.64" for 40 Hz tuning, 8.18" for 30 Hz:

[Sweeten to taste.... :p ]

If anybody expects these're gonna suck, tell us now, please....

Robh3606
07-06-2005, 06:08 PM
"If somebody expects these're gonna suck, tell us now, please....'

I can see them being killer! I would love to hear them if they get built.

Rob:)

Zilch
07-07-2005, 12:13 PM
As designed = yellow
Assisted = green (Q = 2 at 45 Hz)
"Extended bass" = magenta (6.25 cuft)

Excursion limits kill all at 38 Hz.

Assisted alignment is "protected".

Bigger box is fruitless. E145 don't hunt below there.

Disclaimer: I been usin' BB6P less than an hour.... :p

Zilch
07-07-2005, 12:34 PM
Perhaps top and bottom panels non-parallel as that will be the source of the lowest standing wave mode.:hmm:

O.K, it's gonna get a "wedgie" base, then.... :applaud:

Izzat enough to break up the standing wave?

I yanked it down 1" at the rear.

[LOOKS cool enough.... :p ]

Helps with the port location problem, too, 'cause they can go lower without running into the bottom insulation, there.

Volume inconspicuously "grows" another 0.096 cuft.

Good tip. Thank you. :bouncy:

clmrt
07-12-2005, 07:35 PM
:applaud:

I disassembled the 2404 and took photos of the repair process. Battery died after a few steps, but I think it's documented well enough. I'll post a seperate thread on it.

They sound great - no regrets.

:bouncy:

clmrt
07-13-2005, 07:26 AM
And sensitive - I have the home theater trim -9 to compensate. They scream with just a few watts.

BooBoo Magoo
07-13-2005, 07:55 AM
Yeah...

They aren't real introverted are they.

clmrt
07-13-2005, 10:42 AM
Just got back from a "lunchtime fix"...


PBJ = Natural Smuckers PB and Cherry preserves on whole wheat.

Songs -

A few from each:

The Who, 20th Century Masters
Pink Floyd, DSOTM

Average level = 90db, C weighted

HOLY CRAP!!!!!!!!!!!!!!!!!!!!

:blink: :D :blink: :applaud: :blink: :D :blink:

Zilch
07-13-2005, 12:48 PM
You've got them in the corners there, so you're probably getting good bass outta them, too!


:D :D :D

clmrt
07-13-2005, 01:26 PM
I should measure it, but it sounds much better with the sub blended tastefully in, nice and subtle.

Zilch
07-17-2005, 10:53 AM
Dahlquist, too:

Lancer
07-17-2005, 10:57 AM
Dahlquist, too:You boob! Don't spring surprise photos of crap like that on this forum! Now I have to go stare at something else for a couple hours to try and get that image out of my mind.

Not cool dude. :no:

Zilch
07-17-2005, 10:59 AM
Not cool dude. :no:At LEAST it's inna cage! :D



I should measure it, but it sounds much better with the sub blended tastefully in, nice and subtle.Where's yer sub, in the ottoman there? :)

clmrt
07-17-2005, 02:53 PM
I've thought about doing that - on casters, wheel it around...


Still enjoying these in stereo now that they are repaired. Thay are completely awesome, like totally!

DIY cabinets on the drawing board - simple first. Z2 down the road.