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Mike C
06-14-2003, 04:56 AM
Hi guys, does anyone have or know where I can source the plans to build a pair of 4345 monitors?
thanks Mike

boputnam
07-10-2003, 08:55 AM
Hey, Mike...

I intend on starting some resurrounds on my 2245H's and 2122H's this week-end. So, I'll have the cabinets in some very vulnerable positions for some pics (something with a boa, perhaps...? :D ) and measurements.

Let me know if you're still interested and what you are needing, and maybe I can start collecting for you.

Mike C
07-11-2003, 04:11 PM
Hi Bo, yes I'm still very much interested. I would appreciate any pics measurements and also any copys of owners manuals you may have. I want to build a pair of these things, but want them tobe as close to the real thing I can get!.
thanks so much for answering my post.
Mick.

boputnam
07-11-2003, 08:44 PM
Hey, Mike...

Pleasure, man.

I've no engineering plans - I'm (unfortunately... ;) ) only a recent caretaker of this wonderful design. And, like Don, being an ethusiast of vintage, would love to perpetuate the knowledge, in any way I can.

I will photo a-plenty, and measure best I can. I can forewarn - I've already been "inside" these badboys, and they are really built. "Brick crapper" comes to mind.

And, to a pm received, this iteration has the 4-1/8" by 8-1/4" ports (x 3).

I have "surprise" company arriving this weekend, and so that may slow the project. But, I'll post what I can, when I have it.

ps: lurking behind the twins, is a Sony 50-in LCD flatpanel, struggling to be scale!

boputnam
07-11-2003, 08:59 PM
I need to add the 4301B's I'm reconing, and my refurbished 4312's L/R, but even with all that, it won't approach Tom's stellar collection. :)

Mike C
07-12-2003, 06:30 AM
wow! how cool are these things, mate they are mint. So tell me how do these babies sound? . I have got at the moment all these drivers apart from the 2245's( I have 2241's) in individual enclosures and they sound pretty fat!. Having seen yours I am keen to get my new bins started. Tell me, what blue would be the baffle be on these things?
talk more soon.
Mick.........

boputnam
07-12-2003, 07:18 AM
They are simply quite astonishing. A seemingly near-perfect selection and alignment of transducers paired with well-thought-out networks and active crossovers. Smartly, the UHF are at-or-near sitting height - no stands or height adjustment needed. JBL engineers must've had Carte Blanch when designing these.
:cheers:

Every track is a new experience - whole lots of texture not before present (or at least audible... ;) ). The responsiveness of the 2245H's is every-day surprising. No sluggishness or muddy character at all - quite to the contrary. And, they don't need high gain - they only need be on to get everyone's attention.

I am a REAL lucky boy to have a chance to caretake these - and that all before me babied them so. And even more - to have a wifey who is lettin' me do it :D. She has become quite smitten with them! She groaned (not the good one... :eek: ) when I unboxed them, but they absolutley "sell" themselves.

They have become not only the visual "center" piece of the redone family room, but are the conversation piece all the while. As a matter of fact, I drafted-up plans for a wall cabinet with cubbies for these and a doored/roll-in area for the rack, and proper LCD TV space, but cabinetry of the 4345's and overall look is too good for that - so, we're stalled with the temp set-up you see, for now.

steveh
07-12-2003, 11:24 AM
The 4345 project looks interesting. Having most of the components, I was wondering if 2441 diaphragms be installed in 2440's and deliver the 2441 performance? Thanks for any advice with regards to this question.

boputnam
07-12-2003, 12:25 PM
Hey, Steveh...

Welcome! :wave:

And, I don't know about 2441, but here's a Link to some Forum discussion on the 2421B (the compression driver in this pair of 4345's), and possible diaphram swaps: http://www.audioheritage.org/vbulletin/showthread.php?s=&threadid=350&highlight=2421b

boputnam
07-13-2003, 08:55 PM
Be patient, and I'll slowly characterize these things. Frankly, its summer and there's many distractions and others calling for my participation and attendance! :smthsail:

Not much to report, but here's a close-up of the 2122H dog house baffle cut. The dog house interior dimensions are 14.5" wide by 10" high by 6" deep- completely sealed, and loosly lined with the batting shown.

Mike C
07-14-2003, 01:11 AM
Hey Bo, thanks for the info mate, keep it coming but please don't let it get in the way of your R&R:cool:
Mike.

boputnam
07-15-2003, 06:26 PM
Here's some pics of the front baffle, with measuring tape for scale.

Note the baffle front (inside the molding) measures 39 inches height, by 28 inches wide (sorry - we are NOT going metric :no: )

I tried no flash (not distinct enough) and ended-up thinking flash is better, but to mitigate flashback (oh NO!! :shock: ) I had to be slightly off axis. Let me know if these are not useful - here goes...

In response to some inquiries, I thought this series might be the best way to allow those interested to triangulate the center of the baffle cuts. If needed, you can "right click" on these and save them and enlarge in "Paint" or other graphics software for better viewing.

NOTE: All pics are with scale zero-end at baffle-left or baffle bottom.

boputnam
07-15-2003, 06:27 PM
across the 2405 and 2421B

boputnam
07-15-2003, 06:28 PM
across the 2122H (nice clean resurround job... ;) )

boputnam
07-15-2003, 06:29 PM
across the 2245H

boputnam
07-15-2003, 06:30 PM
across the ports

boputnam
07-15-2003, 06:30 PM
along the ports

boputnam
07-15-2003, 06:31 PM
"along" the 2245H

boputnam
07-15-2003, 06:31 PM
"along" the 2122H

boputnam
07-15-2003, 06:32 PM
"along" the 2124B

boputnam
07-15-2003, 06:33 PM
"along" the 2405

boputnam
07-15-2003, 06:34 PM
along the Lpad

boputnam
07-16-2003, 02:20 PM
(and in response to pm's from members on this...) my thinking was readers could use both the distance from baffle-left and distance from baffle-bottom to get a quasi X-Y coordinate of transducer centers. The center is where you would be positioning the router jig, hey? As example, the 2405 is 9" from baffle-left, and 34-1/4" from baffle-bottom. Make sense? This would reflect the most sensible way to replicate baffle-position related transducer imaging.

Or, simply put: :blah: :blah: :blah:

boputnam
07-27-2003, 07:19 PM
First, straight in showing the back bracing and position of the network.

Those are towels placed around the opening to rest the LF on.

boputnam
07-27-2003, 07:20 PM
Toward the left side (this is the RH cabinet).

boputnam
07-27-2003, 07:21 PM
Toward the right side (RH cabinet).

boputnam
07-27-2003, 07:23 PM
Looking up, toward the 2122H dog house.

Bracing is 1" thick
On back is 10-1/2" separation.
On sides is positioned ~12-1/2" from base.

Robh3606
07-27-2003, 08:12 PM
Hey Bo

What is the center to center for the midrange horn to the slot center?? Great pictures!!

Rob:)

boputnam
07-27-2003, 08:59 PM
Hey, Rob...

You can see that in a post of like name. It's on the first "page" of this Thread.

All measurements are made in from left-edge of baffle, and up from bottom-edge of baffle.

Earl K
07-27-2003, 09:28 PM
Hi Bo

Great pictures !!! I'm really enjoying them . I'm not planning on making 4345s , but I always do enjoy a peek under the hood . Since you have a lot of blue-faced wonders , is there any chance of you taking a small sample (box) to a paint store to get some computerized color matching info for the rest of us ( the DIY crowd ) ? I don't think in any of the past forums we've actually had a definitive on just what JBL blue actually is ( or maybe we did & I was AWOL that day ) . If the store needs a minimum purchase made - find out how much - PM me - & I'll consider financing this expedition through PayPal if possible .

regards <> Earl K :cheers:

boputnam
07-28-2003, 06:58 AM
Hey, Earl K...

I was thinking this weekend about tossing one of the dwarfs (4301B's ;) ) into the truck and seeing if they could match the baffle color. I don't think they're much computerized in these parts, but we'll see... Maybe Widget has the means?

Whatever JBL used, there was almost indiscernable batch effects - that color is identical on my 4345's, 4313B's and 4301B's. Same-same-same with the grill cloths. :hmm:

Tom Loizeaux
07-28-2003, 07:34 AM
Bo, Interesting photos. I enjoyed them.
Are those original stock crossovers? The crossovers in my 4333s and 4343s are housed in a large metal box with terminal strips and point to point wiring, covered with a perforated metal screen. I'm surprized to see that yours are different.

Tom

boputnam
07-28-2003, 07:48 AM
Hey, Tom...

"Are those original stock crossovers?

Near as I can tell. I had them mostly out, and partly dissassembled, yesterday for a member's (regrettably unrequited... :( ) request. There is no sign they are anything other than the Real McCoy.

boputnam
07-28-2003, 06:03 PM
Earl K...

I remembered a "laugh" wrt your suggestion of getting "color consulting" done...

Once time, I took a tired-old LE10A that someone had spilled something onto the face of, and went looking to try and match the old off-white Aquaplas face with some touch-up paint. This was the vintage LE10A with the fine, shiny white flecks of what look like maybe gypsum. Well, the HipHop boys manning the paint department were astounded by the size and weight of the motor, but were absolutely befuddled at, and insistant on changing, the white face. "It oughta be black, man - just not right..."

They thought I was, well, at the least, bi... :smsex:

Ha!

Ian Mackenzie
08-03-2003, 04:55 AM
Bo,

Regards the pics I'm impressed with your measurements.

I have one question however which may help us Slot fanatics extract the last once of HF performance.

Exactly how far proud does the lip of the 2405 Slot clear of the front baffle? It looks to be an 1/8 inch or so.

This is a key measurement given the small wave lengths at the crossover point, and may also effect HF dispersion and imaging.

regards

macka

Earl K
08-03-2003, 07:41 AM
Bo, Yes, again , great effort at providing pics and measurements for the 4345. With all the other available information including crossover schematics, it should now be pretty straightforward to build up a pair ( but of course, not cheap ).



befuddled at, and insistant on changing, the white face. "It oughta be black, man - just not right..." :scold: :coolness:

Well, I guess being the contrarian that I am, I prefer white cones for HiFi. (Helps keep me from getting confused & thinking that I'm listening to my black-faced SR gear - :bs: :) ).


I bought a mint pair ( NIB ) of ancient le10a woofs that I refurbished the LansaLoy surrounds on. Alas, I got one small dot of brake fluid on that "gypsum" faced white cone. Stained it like the dickens - the size of a quarter.

- Did the HipHop boys ever successfully match the off-white color( or get close ) ?
- Or did they manage to send you into retreat mode ?:duck:

regards <. Earl K

boputnam
08-03-2003, 12:40 PM
"Exactly how far proud does the lip of the 2405 Slot clear of the front baffle? It looks to be an 1/8 inch or so." Hey, Ian...

Sorry, for the unfairly delayed reply - I'm "moving in" to a new EQ, and, well, er, you know... :banghead:

The distance from face of baffle to face of these 2405's is 25/100ths inch. I say these, because there are some slight modifications to the 2405's from this vintage to today's.

On this vintage 2405 (16-ohm), the length of the "throat" is exactly 100/100ths inch. But, you can see in the attached from the current 2405 (8-ohm) brochure (JBL Pro 2405 Component Link (http://www.jblpro.com/pages/pub/components/2405.pdf)) the throat is 1-1/16 inch.

On the vintage 2405 (16-ohm) the mounting flange is also 25/100ths inch. I somewhere have a schematic for the vintage 2405, but it must be on my harddrive at work, and I won't be there 'til Thursday...

Hope this helps :D

boputnam
08-03-2003, 12:51 PM
"Did the HipHop boys ever successfully match the off-white color( or get close ) ? " Hey, Earl K...

Yea, they did. There's a kid here who has sniffed all sort of vaporous things and does a really good job matching paint.

However, each white-boy cone is it's own unique shade. Over the years they fade differently, and are colored by their surroundings (or spills... ;) ). So, I've got 4 half-quarts (smallest batch they would mix) for the 4 cones I matched - and I used like two dabs from each. Perfection, has its costs...

But, what the heck were you doing with brake fluid on those LE10A's - some new hydraulic damping? Huh? COME ON, GIVE US YOUR SECRETS!! :rotfl:

Ian Mackenzie
08-03-2003, 01:52 PM
Hi Bo,

Got you on those specifications.

At the moment I'm drawing up a new " super baffle " for 4345 clone thanks to your assistance.

It should look cool when I'm finished.

Thanks again for your help.

Cheers

Ian

Mr. Widget
08-03-2003, 02:37 PM
Bo, the brake fluid softens the old stiff lans-alloy surrounds.

Earl, I would recommend that you air brush the stain. That way you won't add any more mass than is absolutely necessary. Start with an off white that is a close match and blend it in. If you can find an artist friend to do the work suggest they use designers gouache. It is very opaque and matte so very little would be required.

boputnam
08-03-2003, 02:58 PM
"brake fluid softens the old stiff lans-alloy surrounds." Well, that would save quite a bit of work. ;) Every one I've come across has not only been "stiff", but cracked as well, so replacement was the only route...

Tom Loizeaux
08-03-2003, 05:54 PM
The 2405s in my 4333 and 4343 cabinets, when mounted from inside the cabinet using the rubber gasket ring, barely protrud and are basically flush with the front baffel with is 1" thick.

Tom

Earl K
08-03-2003, 07:48 PM
Hi All

Thanks for the air-brushing advice Mr Widget. :)

Bo, heck no, I haven't been holding out on this topic. Most of the chat on the topic "departed" with the implosions of all the previous forums. That's not really such a bad thing, because to successfully mess around with this technique, people must be able to do Fs measurements plus have a lot of patience. I thought you're posting of the pictorial step by step "refoaming a surround" was brilliant - BTW .
This forum does contain a bit of my info on the "brake fluid thing" buried deep within a thread, called 2235 Break in Time (http://www.audioheritage.org/vbulletin/showthread.php?s=&threadid=122&highlight=brake+fluid) .

regards <. Earl K :)

GordonW
08-03-2003, 08:27 PM
Originally posted by Mr. Widget
Bo, the brake fluid softens the old stiff lans-alloy surrounds.

Earl, I would recommend that you air brush the stain. That way you won't add any more mass than is absolutely necessary. Start with an off white that is a close match and blend it in. If you can find an artist friend to do the work suggest they use designers gouache. It is very opaque and matte so very little would be required.

Have you tried plain old pure alcohol (the main solvent in brake fluid)? I've found alcohol to be able to dissolve/soften/de-gunk many of the old surround materials and glues, without screwing up the stuff you want to keep...

Regards,
Gordon.

boputnam
08-03-2003, 09:17 PM
Heck, Earl...

I find that in participating on this forum, for the decades I was hefting pro-audio gear for my numerous efforts (and equal number of bands... ;) ) at LIVE sound, while largely ignoring the home gear (or at the least, suffering through store-bought gear...) I learn a great deal from y'all who have done the obverse - spending decades of paying strict attention to all this. Your experiences are vast, and priceless.

I only hope we don't lose this Forum, too. Don? Let us know when finances ar crimping the model. We're always ready... :yes:

boputnam
08-28-2003, 07:08 AM
For any interested, Ian and I have beem emailing on whether the MF 2122 is centered, or off-set, within the "doghouse" subenclosure. I think we have sorted the mystery, but I will make confirmatory measurements this weekend. Here is an excerpt from an email to Ian:

*****

Hey, Ian...

Your logic appears spot-on. But, I have attached a more compelling picture, and perhaps better guesstimate to your question. This view is looking into the baffle-cut for the 2245H, up toward the doghouse. The 2245H is centered in the baffle, as you know.

The perspective is disorienting, but the view is from the base of the cabinet upwards into the cabinet body. This is of the RH cabinet, thus the ports are on the right. The vertical bracing holding the network is centered on the cabinet back, and thus, so is the 2122 doghouse.

The baffle width (measured inside the molding) is 28 inches wide.

Therefore, using the LH cabinet (where all the photos with the measure tape are collected), since the 2245H is centered, but the 2122 and 2421B are aligned but off mid-line (to the right in LH cabinet), and the approx. center of the 2122 is 17-in from baffle left edge (see relevant view on this Thread), versus baffle vertical mid-line at 14-in from baffle left edge, the 2122H is exactly 3-in "inside", or to the right of the mid-line (3-in right of mid-line in the LH cabinet, and 3-in left of mid-line in the RH cabinet). Thus, the 2122 is not centered within the doghouse.

Make sense? :thmbsup:

boputnam
08-28-2003, 07:20 AM
Looking at some photos of 4343's, I wonder whether the 2121 MF is mounted above subenclosure center point, for the same reason.

But, I'm (again...) out on a limb, here... :duck:

boputnam
09-14-2003, 05:32 PM
For completeness, here is a shot through the rear access panel. The 2421B is removed, so you can see through, out my window to the neighbors...

The 2307 is mounted to the baffle, and the 2421B motor is held by a bracket that bolts to the motor-horn join, and then wood-screws into the back of the 2122H subenclosure.

So, I think that's it.

Any questions, post 'em or pm 'em. Good Luck! :thmbsup:

Class, dismissed... :smthsail:

Ian Mackenzie
09-15-2003, 03:23 AM
Bo,

You never told us your 4345s (she) has rear entry for easy access.

Got any more tricks Bo!!

Mind you how else would one be able to service the drivers.

Ian

boputnam
09-15-2003, 07:09 AM
Originally posted by Ian Mackenzie
You never told us your 4345s (she) has rear entry for easy access. Why, I thought everybody knew that! :yes:

That is the boot of the 4345. Where do you think we store all those illicit recone kits? :rotfl:

boputnam
03-14-2004, 06:36 PM
Hey, Ian...

I thought I'd better tag a reply to this long-ago Thread - there's quite a few dimensions and such you hassled me through (damned Aussie...) and maybe some of the newer fans haven't-yet stumbled this far into our collective past...

Ian Mackenzie
03-14-2004, 09:22 PM
You are entirely correct Bo,

My error.


One of the problems is that unlesss we use stickies, many of our valuable threads disappear, and are only visible to new users for 30 days...as I understand it.

Perhaps we can twist Dons arm and move this and the build thread into a special area

Ian

Well we better get qualification on that, Don mentioned as much in conversation the other day.

4313B
03-15-2004, 04:17 AM
Wow, I guess I didn't know that. I've sure been wasting time posting on this forum. No wonder the same old shit keeps coming up over and over again.

boputnam
03-15-2004, 07:28 AM
Yea, that is in-part why I've adopted the Try the Search Button (you dope... ;) ) mantra. It is an amazingly powerful tool, even on so poorly organized a database as is this.

And, that has encourged me to properly label all posts - particularly when there is only an image being posted. Without a label, that image is unattributed (not tagged) and is lost to the ether...

maxwedge
03-15-2004, 08:42 AM
Originally posted by Giskard
Wow, I guess I didn't know that. I've sure been wasting time posting on this forum. No wonder the same old shit keeps coming up over and over again.
Your time's not wasted.:no: I just wish you wouldn't be so quick on the delete key.:)

boputnam
04-08-2004, 10:27 PM
Hey, Giskard...

Stumbling around last night, I discovered (loosely used...) that while the active 5234A and passive 3145 networks both crossover at 290Hz, the 5234A uses an 18dB slope, while the internal passive 3145 uses 12dB.

I apologize if we (or you all...) covered this before, but wonder why the passive was not engineered with the same slope as the "preferred" bi-amp active option...?

Mr. Widget
04-08-2004, 11:33 PM
Bo,

I believe JBL used the 18dB card to build a tweaked 12dB circuit for the 51-5145. I believe this "tweaked" crossover was to correct for the upper bass bloom that I discovered in my earlier 4355 experiments.

Widget

Ian Mackenzie
04-09-2004, 02:12 AM
I have recently looked at this odd thing myself.

The 51 5145 card values are a standard 18/18 slope 290 hertz curve. Giskard has modelled that more me recently while I have been quietly developing a more current active network for the 4345/4344 system down here in the deep dark southern hemisphere.....with an Americana Pizza thrown in for good measure. Just waiting on some special juicy parts.

More enlightening however is comment from Greg Timbers:

"Bi-amping, bypassing the input inductor, almost always gives better and tighter bass performance. However, most electronic crossovers have fixed crossover slopes and shapes and our passive crossovers are custom tailored for the response of the specific drivers used. This usually results in more precise acoustic drive parameters. You will note that the specifications call for 290 Hz for the electronic crossover and the passive one is 320 Hz. This was done to get the best response possible from off the shelf electronic curve shapes.
The bottom line is that an electronic crossover on this system probably will sound better than the internal passive, but it is a bunch of extra parts and trouble. "

So, there you have it.

That email is now taken pride and place among others in my Audio Hall of Fame.

I can't wait to commune with Bo's 4345's .

cheers

Ian

4345
04-09-2004, 05:00 AM
Bo,

So, your 4345's have a 2421b(alnico) and 2405h(ferrite). I would have thought both would be alnico. Do you think it was done at the factory like that?

subwoof
04-09-2004, 05:17 AM
Mine have alnico 2405's and 2421B's but the network / cabinetry is the same as bo's.

Another cool option for biamping is the urei ( pre jbl ) 525 crossover. Since it has 18db slopes, it can be precisely adjusted to 290hz via the front panel frequency counter which actually measures the resonant freq of the crossover point by making it feedback ( ring ) slightly when the momentary switch is engaged.

And if you use in in stereo 3 way mode, and change the first 2 section's filter caps to 2X the original, you can use those as HP filters down to 20hz.

The internal output buffers and xformers can be ignored and the signal picked off earlier for those who fear iron and class B....

:)

sub

Ian Mackenzie
04-09-2004, 05:34 AM
The Spice curves.

One of the things I am looking at is S/K filter options for unity gain like the JBL cards or equal component values that offer easy adjustability of crossover point, slope and Q but the higher order filters and high Q options have gain in the passband.

See also Giskards graphs here
http://www.audioheritage.org/vbulletin/showthread.php?s=&threadid=462&highlight=4345+voltage+drive



Ian

Mr. Widget
04-09-2004, 09:15 AM
I guess I got my wires crossed. Too much cross talk in my brain. Perhaps it was a different JBL monitor that used the 18dB card for a "special" curve.... hmmmm.

Ian Mackenzie
04-09-2004, 10:42 AM
I can see me casting my L100 off after laying eyes on those darlings.........



Ian

Mr. Widget
04-09-2004, 10:49 AM
You guys are sick, they're only speakers.

OMG, what have I said....:confused:

Ian Mackenzie
04-09-2004, 11:04 AM
No No,

Today is officially JBL Blue day...even down here.

Ian

Alex Lancaster
04-09-2004, 11:13 AM
Giskard:

I thought You could not use profane words, like You just did, in these forums.

boputnam
04-09-2004, 11:45 AM
Originally posted by Ian Mackenzie
More enlightening however is comment from Greg Timbers:

...You will note that the specifications call for 290 Hz for the electronic crossover and the passive one is 320 Hz. This was done to get the best response possible from off the shelf electronic curve shapes. :confused: That is most odd, because the graphics I posted show that the passive internal crossover was 290Hz. Odd...

You boys been BUSY this morning...!!

Oh, and subwoof - you are correct (good eyes... ;) ). That is the 2405H. The only AlNiCo motor in these is the 2421B - which Widget thinks I've otherwise luckily "tamed" quite pleasingly in my setup/EQ. There is no indication anything in these had been tampered with, except one of the 2245H's which look like someone dropped a screw driver through it, and after repairing the pierce (oh no - more white glue noise...!! :shock: ) re-installed it in a non-factory orientation. But I have two new 2245H's that are going in those gaping baffle cuts... :yes:

boputnam
04-09-2004, 01:23 PM
Originally posted by Giskard
...electrical ... which means active. Yea, exactly right. Odd this was on the 4345 brochure, while the 5234A is a separate, and obviously, quite tedious, part to work with... :rotf:

Then again, I can see where tri-amped is somuch simpler... :spin:

Thanks, dood... :thmbsup:

boputnam
04-09-2004, 02:27 PM
Yes, indeedy... :yes:

From this:

Robh3606
04-09-2004, 02:29 PM
Hey I want a copy:bouncy: :bouncy:

Rob :)

boputnam
04-09-2004, 03:31 PM
Dood...

No sweat - pm me your email, and you'll get filled!

Ian Mackenzie
04-09-2004, 03:39 PM
Done it already


Ian:cool:

boputnam
04-09-2004, 04:33 PM
I know. Buy YOURS is printed upside down... :spin:

Ian Mackenzie
04-09-2004, 04:52 PM
Oh,

Okay..

Better post the original.........with the instructions.......from our Legend Greg Timbers.

I should point out that without his kind assistance we certainly would not be where we are today with these Forums. Take it away Greg Timbers....

"I have attached some internal Engineering Specification sheets for the 4345 system. I hope they prove useful.


I do believe the gross (excluding the MF sub enclosure) volume on that system was 9 cu.ft. The fiberglass lining adds volume in about the same amount as the stiffeners and back side of the woofer subtract it - giving a net internal volume of 9.The enclosures were lined with 3/4" fiberglass on all surfaces but the baffle. I don't have accurate records of the tuning frequency, however, the impedance curve indicates around 26 Hz. That method usually reads a little lower than the effective tuning when real motion is occurring. I would guess that 27 - 28 Hz is what the system really was. The tuning was somewhat empirically done, based on the results of listening tests. One can change the tuning frequency of that system by +/- 2 Hz and still get a very presentable low frequency curve. It really came down to the preferred sound character. The DCR of the LF inductor will have an audible effect on the sound in the tuning range. The inductor in the 4345 had a DRC of around 0.5 ohms. Your 0.2 is a better number (unaffordable for us in production). It might result in the need to raise the tuning frequency by 1-2 Hz. Your choice of tuning will not hurt the woofer any and should be done to satisfy your taste.

Good luck with your project. "

Greg

Ian Mackenzie
04-09-2004, 05:00 PM
The graphs

Ian Mackenzie
04-09-2004, 05:08 PM
The graphs

boputnam
04-09-2004, 06:07 PM
You're making me weak in the knees... :D

Ken Pachkowsky
04-10-2004, 03:47 PM
Stop posting pictures of these damned things BO!!!

To quote Julie:

These sound really good but your old 4345's looked much nicer!

Well, at least they went to a good home. I must admit that I do miss them.

boputnam
04-10-2004, 03:57 PM
:rotfl:

It ain't me!! It's been Giskard, Ian, and whomever needs a fix! I was surprised to see them, too! But, I did give them cute 4313B's a hug for my buddy Giskard. ;)

Oh yea, Widget had his first sampling of the 4301B's last night - it was early in the liver abuse process, so he should recall. He ended the evening pretty close to Dead center with Annie Lennox' Medusa at his volume He walked outa the house like this :D ...

Ian Mackenzie
04-10-2004, 04:05 PM
About to go from dark to JBL Blue this end.......wow

Will post some worthy pics when done

Ian

Ian Mackenzie
04-10-2004, 04:10 PM
It ain't me!! It's been Giskard, Ian, and whomever needs a fix! I was surprised to see them, too! But, I did give them cute 4313B's a hug for my buddy Giskard. ;)

Bo, would you mind posting a close up of those 4313's. Gonna need to think seriously about building up a pair, I bet they sound Cool.

Ian:dancin:

boputnam
04-10-2004, 04:59 PM
Originally posted by Ian Mackenzie
...would you mind posting a close up of those 4313's. Gonna need to think seriously about building up a pair... :scold: No, no, no. JBL Evolution goes the other way... :rotfl:

Ian Mackenzie
04-10-2004, 05:55 PM
Okay, pair of Micro 9800 mini's then


Ian

boputnam
04-11-2004, 03:54 PM
MY wifey got tired of the old photo, and wanted to assure other wifeys out there, that while she agreed the 4345's in the family room, they needed proper presentation! :rotfl: No wires, cabling, or racks (or fans!!!).

Here it is...

Ken Pachkowsky
04-11-2004, 03:57 PM
I give up Bo!

Where did you hide the rack?

Ken

Ken Pachkowsky
04-11-2004, 03:58 PM
Has anyone found the dark blue JBL grill cloth yet?

Ken

Ian Mackenzie
04-11-2004, 04:16 PM
Hey Bo,

Does Suz keep having to buy new candles because they keep vibrating off the table or have you felt pads under everthing?

Seriously, my entire bar full of glasses literally rings on certain bass notes.

Ian

4313B
04-11-2004, 04:23 PM
Originally posted by Ken Pachkowsky
Has anyone found the dark blue JBL grill cloth yet?

Ken I checked again the other day and it allegedly isn't being used at all in the States. Just black.

boputnam
04-11-2004, 04:56 PM
Originally posted by Ken Pachkowsky
Where did you hide the rack? In the pantry... No kidding. My own little sound booth. :D

I 'spose now you want a picture of that...??!!

Ken Pachkowsky
04-11-2004, 05:02 PM
A pantry......................Hmmmmmmmmmmmmmm


Honey!!! Have ya got a minute?:scold:

boputnam
04-11-2004, 05:06 PM
:rotfl:

Yea, we agreed to sacrifice our secret repair to get the rack out of sight... :(

Ian Mackenzie
04-11-2004, 05:47 PM
Yeah, Have industrial hardware in the family quarters would be a bit abstract

Anyways , Glad your not doin that Bose Lifestyle Thing!

Ian:rolleyes:

Guido
04-12-2004, 03:56 PM
Thanks Ian for the system spec.

I think the page 2 is missing and page 3 is double. Could you fix this?
Thanks!

boputnam
04-12-2004, 08:16 PM
Damned Aussies... ;)

Ian Mackenzie
04-12-2004, 10:21 PM
OOPS,

Thanks Bo,

Hey my 4345 (diy) is now true JBL Blue..yippy

regards

Ian

Ian Mackenzie
04-30-2004, 06:08 PM
Well the benefits of proper EQ cannot be under estimated.

Just been demo'd Smart Live, a precision measurement package, the FFT gives a true account of whats really going on.

The difference with EQ done right, even when subtle is very noticeable.

Damn Yankee, and those 4345 are sweet.

Back to the Bad Boys WOW

Ian :eek:

boputnam
01-04-2005, 08:06 PM
Just to keep things current, and properly cross-referenced:

The 4345 Foilcal has some close-ups, with scale.

boputnam
11-30-2005, 05:25 PM
Hey, Ian...

Here we go. These are tricky - can't use flash because of glare off the tape. With no assitant, here's what I mananged.

The grill is 2.75 inches (7 cm) thick, with the front slightly smaller than it's back. I will leave it to you to determine absolute dimensions from these pics.

First, height of FRONT edge of front of grill:

boputnam
11-30-2005, 05:28 PM
OK, now width of FRONT edge of front of grill:

boputnam
11-30-2005, 05:32 PM
Height of BACK edge of back of grill

boputnam
11-30-2005, 05:34 PM
Width of BACK edge of back of grill...

boputnam
11-30-2005, 05:36 PM
Edge of grill - front is to bottom of picture.

Note the flat edge that nests into the cabinet...

boputnam
11-30-2005, 05:38 PM
Back of grill, grill on it's side (top to left)

The second shot is into the grill (on it's side), showing the framework.

ibid, in upright position (showing base interior of grill framework).

Ian Mackenzie
11-30-2005, 09:18 PM
Bo,

Thanks for your prompt assistance


Ian

boputnam
01-14-2006, 03:50 PM
Rolf's URGENT plea for the 4343 "List" (which I interpret to be "lip"), reminded me we never posted these cut-aways of the edge of the 4345. I believe they are identical for the 4343, etc. The Widget collected this info - so you know it's right! :yes:

saeman
06-17-2006, 01:29 PM
I wanted to post these earlier but they needed to be cleaned up and made a bit more presentable. All of the dimensions on the attached drawings were taken from actual cabinets. I would urge any interested 4345 owners to bounce the data off their actual cabinets.

I have a few other detail drawings I will add later but the info here is sufficient for use should someone decide to start building.

Note that I have labeled the port diameter as 4" I.D. The cabinets I took these numbers from were actually 4 1/8" I.D. Earlier in this thread Bo posted some pics with a tape measure layed across one of the ports. From that pic the diameter looks closer to 4 and definately not 4 1/8. I would hope there are both out there. Tubes with 4" I.D. are readily available. 4 1/8" will be hard to find.

Rick

saeman
06-17-2006, 01:32 PM
A few more pics

saeman
06-17-2006, 01:39 PM
I thought this stuff would end up in the DIY category. I did a search to find the old thread and just added on. Moderators - please move it if you think it belongs there - maybe as a new thread - although all the info should stay together. Sorry!

Ian Mackenzie
06-17-2006, 01:51 PM
Excellent.

4313B
06-17-2006, 02:14 PM
All of the dimensions on the attached drawings were taken from actual cabinets. I would urge any interested 4345 owners to bounce the data off their actual cabinets.

I thought this stuff would end up in the DIY category.Once it is verified Techbot will put it in the read-only forum.
Thanks once again Rick.

Ken Pachkowsky
06-17-2006, 02:31 PM
I thought this stuff

Nice contribution!

Ken

John W
08-27-2006, 11:06 AM
I'm just finishing up my pair of 4345. Thanks for the excellent plans and the volumes of help from the forum for crossover and other design elements.

John W
08-27-2006, 11:08 AM
Here are a few shots from construction

John W
08-27-2006, 11:11 AM
Some more...

Ken Pachkowsky
08-27-2006, 11:12 AM
I'm just finishing up my pair of 4345. Thanks for the excellent plans and the volumes of help from the forum for crossover and other design elements.

John

Your hired!

Seriously, as nice a DIY job as I have seen anywhere. Congrats.

Ken

Steve Gonzales
08-27-2006, 11:18 AM
A true heavyweight JBLer if I've ever seen one. You continue to impress me with your creations. I am in AWE. Well done John :applaud: .

Mr. Widget
08-27-2006, 11:26 AM
Great work as always John. Nice shot of the budding Vanna Whites too. That really puts things into perspective.


Widget

speakerdave
08-27-2006, 12:00 PM
Outstanding work, John--congratulations.

David

Ducatista47
08-27-2006, 12:15 PM
OK, your's are better than mine! After carping as I have about members building 4345's, I shall carp no more. You and Ian have proved that building is well within the realm of possibility. The level of talent and comitment you have exhibited is beyond outstanding.

I hope you don't mind becoming a source of advice for builders and owners, because I am starting things off with some questions of my own.

I was going to upgrade the crossover components of my pair this winter, but your network is obviously a clean sheet. Is it from Giskard plans? Are the plans available on posts in the forums? I see it is charge coupled and involves only two L-pads (so I know you are bi-amping). Most of all, how does it sound? (I know you need some time to evaluate before attempting to answer.) What did they cost, how did you chose and where did you get the components?

The pic of your girls is priceless!

Congratulations, I hope you enjoy them as much as I do, Clark in Peoria

John W
08-27-2006, 12:24 PM
Thanks.
Very nice work on the recones of the 2122Hs SpeakerDave.

I'll post the crossover schematic I'm using tomorrow. Yes, it is Giskards equivalent, but I left the lpad off the 2122h and modified a couple resistors on the 2405 and 2425 to maintain the impedence and reduce the padding a little. Sounds great to me, and measured quite flat on the RTA.
I am still planning on building some grill covers.
I made 4 or 5 attempts on some foilcals, but nothing looked acceptable. Komodo has offered to make some, but the minumum order would be 5. Let me know if you need a pair of emblems, and if there is enough interest I will order some up. Right now, I kind of like the JBL badges put on a dowel and stuck in the LPAD hole, since it isn't being used anyway.

Ducatista47
08-27-2006, 12:38 PM
John, I pulled the grills off mine and am looking at the baffles. I think your very sanitary layout looks much cleaner and better balanced visually than the foilcal and knobs.

Given these and the Piano Black and Maple pairs we can now look at, this is a new game. Since it is the sound we are after, builders can construct them to look like whatever they want them to look like, including original. Obviously, aesthetic as well as sonic improvements are possible. I suppose we owners of originals are bound by tradition to keep the appearance as originial as possible. Score one more for building over buying.

Thanks in advance for posting the xover plans.

Clark

yggdrasil
08-27-2006, 12:44 PM
Incredible:applaud:

speakerdave
08-27-2006, 01:03 PM
. . . . Very nice work on the recones of the 2122Hs SpeakerDave. . . .

I just sent you the frames.

David

John W
08-27-2006, 04:21 PM
I just sent you the frames.

David
Correction.
Thanks speakerdave for the nice frames and a big thank you to edgewound for the great recone job.

Chas
08-27-2006, 05:54 PM
Nice work John, the baffles look better than factory new.

JBLRaiser
08-27-2006, 06:20 PM
:jawdrop:

norealtalent
08-27-2006, 06:38 PM
Incredible work John. Of course I would expect no less. Send me a pm with your address and I'll donate my 4315 foilcals for you to mod. I don't think I'll be in need of them any longer.:applaud: :applaud: :applaud:

Mr. Widget
08-27-2006, 06:57 PM
Send me a pm with your address and I'll donate my 4315 foilcals for you to mod.Mod?

Hell, give him the 4315 foilcals and a couple of weeks later he'll have a pair of better than factory 4315s built to mount them on! :bouncy:


Widget

norealtalent
08-27-2006, 07:05 PM
He already did that. They're 4345's!!!!!!!!! If he wants 4315's I'll throw in the cabs. Local pickup only...


Mod?

Hell, give him the 4315 foilcals and a couple of weeks later he'll have a pair of better than factory 4315s built to mount them on! :bouncy:


Widget

Mr. Widget
08-27-2006, 07:12 PM
Yeah, whatever... you 4345 fans. They are great and all, but John really impressed me with these.

http://www.audioheritage.org/vbulletin/showpost.php?p=83579&postcount=1


Widget

Robh3606
08-27-2006, 07:16 PM
Wow! Just great looking speakers!!!!

Rob:applaud:

John W
08-27-2006, 07:25 PM
Incredible work John. Of course I would expect no less. Send me a pm with your address and I'll donate my 4315 foilcals for you to mod. I don't think I'll be in need of them any longer.:applaud: :applaud: :applaud:
Hey, I'll have a look. Thanks for remembering. When I saw the picture, they sure looked the same, except for the 1 of course.

Ken Pachkowsky
08-27-2006, 07:36 PM
Yeah, whatever... you 4345 fans. They are great and all, but John really impressed me with these.

http://www.audioheritage.org/vbulletin/showpost.php?p=83579&postcount=1


Widget

Shows what a talented guy with the right tools can come up with. Makes me want to build new cabs for mine:) .

Hmmmm....Renton is not that far.........John ohhhh John....

Ken

saeman
08-27-2006, 07:52 PM
When I saw the picture, they sure looked the same, except for the 1 of course.

Hi John: FYI - the foil cals for the 4345 and 4315 are identical in size however the attenuator calibration scale for the 3 pots is totally different - if that makes a difference to you.

Ian Mackenzie
08-27-2006, 09:01 PM
I liked the pics, nice.

Ian

boputnam
08-27-2006, 09:10 PM
Golly gee, dood. You made me go take the grills off mine. Amazing. Truly.

I'm embarrased to admit how many times I've gone through that picture folio of yours. The precision (correction: accuracy) on reproducing those beveled fronts to the cabinet is eye splitting. Wow.

But, now tell us how they sound, and what is the signal path? I had a (re)peat friend/musician over tonight - I know I'm being used. I hope you are as blown away as you should be for the painstaking effort.

But excuse me - I have to go right now. Gotta go mark mine with an "Authentic JBL" fire-brand... :p

John W
08-28-2006, 07:40 AM
The precision (correction: accuracy) on reproducing those beveled fronts to the cabinet is eye splitting. Wow. :p

Thanks again,
The final trim on the fronts was one of the most difficult parts. The beveled angle makes clamping a problem. I installed mine after the veneer,but I might consider adding the front trim prior to the veneer if I did it again.

John W
08-28-2006, 07:54 AM
Here is the crossover information for the network. It is basically Giskard's equivalent network, without the Lpad on the 2122. Since I am set up for strictly bi-amp I can control this level through the active crossover.
The 2122 Lpad account for about 3db, so I modified the fixed resistor Lpad on the 2405 and 2425 to have the same impedance, but 3db more gain.
I used two sources for the parts.
Parts Express for the resistors and inductors and SpeakerCity.com for the Axon capacitors and Lpads. Axon is basically a re-brand of Solen.
I built mine using terminal blocks I bought locally. I screwed the components onto the terminal blocks to make adjustments easier down the road.

John W
08-28-2006, 08:06 AM
Also,
The network is only partially biased. I decided to only use bypass caps on the 2122h zobel and other bits of the network that didn't appear to be in the direct signal path. For bypass caps I used WIMA .01 630v MKP10 capacitors from mouser that I bought with the items needed for the crossover card.
I am open to hearing comments from the crossover experts about this.

I was able to dial the various lpads in using my Behringer RTA to acheive a nice flat response.
The speakers sound awesome, very dynamic and engaging. We have the soundtrack to Pirates of the Carabbean II which really came alive with its great dynamics and thundering bass.

Tom Loizeaux
08-28-2006, 08:43 AM
Great work and wonderful documentation. You've certainly raised the bar!

The folks at JBL should take a good look at your speakers and let it soak in. That kind of appreciation and care on your part should sober them up to the fact that there is still passion for quality speakers out there.
You are a credit to this Forum with your pursuit of excellence and willingness to share. You deserve the pleasure you will get from these speakers.

Tom

Zilch
08-28-2006, 09:42 AM
I am open to hearing comments from the crossover experts about this.I disclaim "expert" status, but here's the thinking from my experience:

Though not in the direct path, shunting elements function by subtracting from the signal. If the subtraction is distorted, what remains in the signal to pass is, as well.

As an economic compromise, I don't bias the LF circuit, just the mid and highs. The large caps typically required are just too bulky and expensive, and it seems the major benefit is to the higher frequencies.

However, if you're not biamping, the same argument applies. Whatever zero-crossing distortion is generated in the LF is being subtracted from the HF and the remainder passed on thereto; thus the LF should be biased as well.

Most fabulous work again, John! :thmbsup:

[I'm still partial to your mod L200t3s, tho.... ;) ]

Ian Mackenzie
08-28-2006, 02:10 PM
John,

Excellent.

I should have my Solen CC up and going in a few days so we can compare notes.

Ian

John W
08-28-2006, 03:10 PM
Though not in the direct path, shunting elements function by subtracting from the signal. If the subtraction is distorted, what remains in the signal to pass is, as well.
That makes sense. I guess I have a little tweeking still left to do, which is a good thing.:)
First I have to put all that nice grill cloth to good use.

Zilch
08-28-2006, 05:04 PM
I guess I have a little tweeking still left to do, which is a good thing.:)Looks like you've got most of it covered; just three more to do, and plenty of room on the board to do it.

I'll be interested to know if you hear a difference.... :thmbsup:

Ducatista47
08-28-2006, 08:13 PM
Thank you for sharing your crossover details, John. The cost of your components are quite reasonable and I am quite encouraged.



The speakers sound awesome, very dynamic and engaging. We have the soundtrack to Pirates of the Carabbean II which really came alive with its great dynamics and thundering bass. They kind of grow on you. The way I hear it, other speakers might have a better this or that, but the whole presentation of the 4345 is difficult to leave behind. Engaging is a nice way to put it. As for dynamic, does a bear relieve himself in the woods?;) The only thing you give up is pinpoint imaging and unrealistically deep soundstaging (which seem to be the current mania of the crowd who pay frightening money for speakers).

Clark in Peoria

boputnam
08-29-2006, 06:37 PM
They kind of grow on you. Not only that, but the 2245H's truly do get "broken in" with time. The new ones in my 4345 have only gotten better - more responsive and more tonal - after one-year in (routine) service. They are an amazing transducer.

gerard
09-04-2006, 10:27 AM
Hello John W

I was impressed by your work and would be interested to make a similar crossover if you do not mind .

The only problem is I do not know about anything in electronic but I can assemble the crossover .

I would like you to answer some questions and forgive me if there are stupid or if I miss something on the thread , english is not my first language :

1. You use an active crossover for Lf : what type and what freqeuncy and slope .

2. I have seen on the crossover picture some very small resistance which appear on the schematic but no value : What are they .

3. There are some conenctions between post I have not seen on the schematic .

4. what mean the bold line on the posts.

5 . Which cable or from which post goes to 2122 - 2425 and 2405 ? I can see "+" , "-" , "B" , "3" does not mean anything to me .

Thank for your support if you can :D

Gerard .

John W
09-04-2006, 04:17 PM
Hi Gerard. Thanks for the kind words and feel free to copy all you want. That is basically what I did too. One thing to note is that I should have charge coupled the three capacitors that show up in the schematic as only being bypassed with the smaller capacitor. See the schematic in the response to question 2 for a proper example.

I hope I can answer your questions one at a time.

1. You use an active crossover for Lf : what type and what freqeuncy and slope .

I am using a JBl/UREI 5235 active crossover. JBL made a special card for these to use with the 4345. Basically it is a 18db 290hz crossover. Here is a link to some additional information, with the schematic for this card:
http://audioheritage.org/vbulletin/showthread.php?t=666&highlight=51-5145

2. I have seen on the crossover picture some very small resistance which appear on the schematic but no value : What are they .

The small resistors here are ¼ watt 3million ohm resistors that are part of the charge coupling in the network. I copied the basic schematic of the crossover from this post by Giskard.
http://audioheritage.org/vbulletin/showpost.php?p=52286&postcount=124
He does a better job of showing how these resistors fit into the plan.

3. There are some conenctions between post I have not seen on the schematic .
I hope not. You may be seeing the red and black wires I used to link up the three channels to the single input + and -.

4. what mean the bold line on the posts.
The bold lines signify soldered connections between various nodes on the terminal strips. These were soldered on the back out of view. Often more than one capacitor or resistors needs to link together so these show these connections

5 . Which cable or from which post goes to 2122 - 2425 and 2405 ? I can see "+" , "-" , "B" , "3" does not mean anything to me .

Check again, I tried to mark which section goes to which driver. “+” and “-“ are the inputs from the binding posts, and “R” and “B” are the red and black posts on the individual speakers. Where there is a “3” it means that the connection is to the third tab of the L-Pad, level adjustment.

Hope this helps and let me know if you need some further clarification.

gerard
09-05-2006, 03:14 AM
Hi John W .

Thank for your info.:applaud:

I will go back to item 3.

A- it seems the + red wire on 2122 post ( horizontal ) is going from (+ left ) to extreme right ( number 10 ) and there goes to the vertical post + on 2425 !.

B - It seems the red wire going from the battery to the 2122 post ( 2nd horizontal ) is then connected to a black wire to first 2122 post ( number 8 from left ) ? .

Than for info .

Gerard

John W
09-05-2006, 07:14 AM
Hi John W .

Thank for your info.:applaud:

I will go back to item 3.

A- it seems the + red wire on 2122 post ( horizontal ) is going from (+ left ) to extreme right ( number 10 ) and there goes to the vertical post + on 2425 !.

B - It seems the red wire going from the battery to the 2122 post ( 2nd horizontal ) is then connected to a black wire to first 2122 post ( number 8 from left ) ? .

Than for info .

Gerard

A - I see your confusion when looking at the picture. The terminal strips are elevated slightly off the plywood. The red wire does go from the + post on the 2122 to the + post on the 2425, but it goes underneath the right side of the top terminal strip. The camera angle makes it appear to be connected when it isn't.

B - In the layout, the small 1/4 watt 3m ohm resistors are used for the charge coupling. The + side of the 9v battery needs to link to each of these resistors. This isn't displayed in the drawing of the layout, but it is what you are seeing in the picture.
I have a big roll of fine black wire that I used for wiring these together. I probably should have stuck with red, but switched to black when linking these together.

gerard
09-05-2006, 08:27 AM
Hi John W

Thank's again , you helped me a lot , this will be my next project ....:bouncy:

Best regards

Gerard Mihel

Ian Mackenzie
09-27-2006, 08:03 PM
Here is the crossover information for the network. It is basically Giskard's equivalent network, without the Lpad on the 2122. Since I am set up for strictly bi-amp I can control this level through the active crossover.
The 2122 Lpad account for about 3db, so I modified the fixed resistor Lpad on the 2405 and 2425 to have the same impedance, but 3db more gain.
I used two sources for the parts.
Parts Express for the resistors and inductors and SpeakerCity.com for the Axon capacitors and Lpads. Axon is basically a re-brand of Solen.
I built mine using terminal blocks I bought locally. I screwed the components onto the terminal blocks to make adjustments easier down the road.

John,

I spoke to WAR audio over here who are closely affiliated with Axon and they advise they are better than Solen capacitors (but made by Solen). I have used them previously and based on my recent experience would have to agree.

Ian

Ian Mackenzie
09-27-2006, 08:10 PM
Here is an interesting Modification.

It has been documented that the mid cone high pass passive filter interacts with the woofer box tuning combination to cause some unwanted gain at and below 100 hz.

I was recently testing full passive mod for my 4345 clones and wanted to assess a new amplifier, the Passlabs X250.5 without resorting to biamping.

I discussed this with Kent English of Passlabs and Kent suggested placing a parrellel resister directly shunted across the 2245 woofer.

Following some experimentation of different values I found 100R and up to 150R made a significant improvement to the system balance..

This is such a simple modification that it is just too good to pass up and I suggest even if you are biamping to give it a try.

Special thanks to Kent for this idea.

Ian

richluvsound
02-15-2007, 01:20 AM
Is there anyone in the UK that has built a 4345 ? It would be great to chat to you about the problems I,m having.
Can any one help me with a swatch of this baffle blue ?. If someone could slap some on a piece of card and pop it in the post to me it would sure make things easier .
regards ,Richard

ayaboh
02-15-2007, 08:27 AM
The blue color is RAL 5007. This is a universal standard, and your local paint shop should have no problems supplying you with some of this stuff. If you want the original JBL look you need to use a spatter gun. It's probably best to get this job done by a professional.

What building problems do you have?

gerard
02-19-2007, 02:28 AM
Hello John W . ( or Anyone can help )

I bought the components to make a similar filter ( takes time to get in Morocco ! ) .

Just the cable to speakers are not clear to me .

1- On the last picture from "page 8 ( 08-27-2006 ) 12:06pm " view for the cabinet , we can see 3 cables going into the filter ?
Binding post + 3 speakers make 4 cables ?

2. On the layout ( see attached ) :

a- it seems cables named 2 is connected to R and R ?
b- there should be 4 cables and I get only 3 ( one is missing ? )
c- I do not clearly understand the "3" to the third tab of L pad ( Normally the 2 speakers wire goes to Lpad and 2 from L pad goes back to spekaer itself ) .


3. I have seen by passed on 5.6 and 2 uf ( what are the values you choose ) .

Again I appologize for the request but I am not technical and It is really unclear to me .

Regards

Gerard

John W
02-19-2007, 08:02 AM
Hopefully I can answer these:

1. In this picture it looks like the input wires from the lower pair of binding posts to the 2245 woofers aren’t hooked up. These crossovers are bi-amp only, so the 2245s are wired directly and don’t show up in the layout. Also, just to make things a little neater I bundled 4 wires into the mesh sleeve for the trip to the top of the cabinet. So in the picture one “cable” is really for the 2425 and 2405

2a) There should be two wires. One from “R” on the 2425 section to tab 1 on the L-pad and then to the red binding post on the driver, and one from the “R” on the 2405 section also to tab 1 on the other lpad and on to the red binding post on that driver.

2b) 4 wires are bundled together in the sleeve.

2c) Two separate wires again, each to tab 3 on their separate L-pad. Individual wires from tab 2 of the L-pads hook up to the black post on their matching drivers.

3. In this drawing the bypass caps are .01uf

Does that clear it up?

spwal
02-20-2007, 08:40 PM
You guys are absolutely amazing. I must have a pair of those. Something tells me they arent cheap money at all -- even in fixer upper condition. Are they >>> L300? what did they list for back when?

thanks

Mr. Widget
02-20-2007, 09:21 PM
You guys are absolutely amazing. I must have a pair of those. Something tells me they arent cheap money at all -- even in fixer upper condition.Clean examples tend to sell in the $5K range... and they are very rare. You'll see 10 pairs of 4350s before you see a pair of 4345s. Your best bet would be to DIY with the info posted here or ask Rick Riessen very nicely, he may build you a pair. He tends to build 4350s, but I'd hold out for a pair of 4345s. The 4350s look awfully badass, but the 4345 is a bit more refined.

Here is an example of some of Rick's outstanding work. http://audioheritage.csdco.com/vbulletin/showthread.php?t=12736


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gerard
02-21-2007, 07:17 AM
John W

Thank you for your answers ! Clear to me .

How can I proove my gratefulness ?
May be pay you a beer in casablanca ? :D


Gerard

gerard
03-04-2007, 10:19 AM
Hello Again John W .

I am soldering the parts ....

I forgot ....

What shall I do with the 20 watts resistor marked "1" and "2". ( the one near 0.27 mh ) .

Where goes those 1 and 2.

Thank's again ;)

Gerard

John W
03-04-2007, 01:41 PM
Hello Again John W .

I am soldering the parts ....

I forgot ....

What shall I do with the 20 watts resistor marked "1" and "2". ( the one near 0.27 mh ) .

Where goes those 1 and 2.

Thank's again ;)

Gerard

Great, hope everything is coming together nicely.
I soldered this resistor directly between posts 1 and 2 on the 2425 LPAD. Have a look at the schematic and it should make sense.

gerard
08-31-2007, 08:30 AM
I just finish my crossover last week .
it took some time to get the parts down in Morocco and make a box etc ...

Here is a picture of it .

My first thanks goes to John W who help me so much to realize a copy of his Crossover.

I also would like to share my impressions .

1. The Xover is extraordinary neutral and detailed .
At first time you do not look impressed but after listening I was able to find that

a- I did not need to listen at high level as I used to do before
b- The set up was quiet easy and the overall sound did not change
at different level .
c- the Xover is very detailed
d- The bass does not look like a Bass reflex , it's so clean even going down.
e- Treble is fine , detailed and full of Harmonics

f-After testing some hard records ( for me ) Davis crosby ( if I could only ...) for the bass , Diana Krall ( the look of love ) for the overall of the cd where bass and treble are different on most systems , I must admit the jbl are now at a very high level and even works better than my 250 Ti clones ( looks there is a competition between the 2 systems in my house !!!) .

Once again thanks to all forum members , I am not technical and I was only able to succed with the forum help .;)

Gerard

Earl K
08-31-2007, 09:27 AM
Hi Gerard,


Very Nice !

I had no idea you were building a 4345 till this thread just popped up ( I guess I've been living on the moon ;) )

Congratulations !

<. cheers

John W
08-31-2007, 09:42 AM
Hey, looks good. Congratulations on getting these together!

I was admiring your work, and something jumped out that you may want to look at. Check out where the red 9v battery wire connects at the arrow here, it looks from the picture that it should be on the other side of the resistor.

boputnam
08-31-2007, 10:21 AM
I made 4 or 5 attempts on some foilcals, but nothing looked acceptable.You guys may have missed this New Foilcals on eBay thread, and the earlier Foilcal Replacements are Available. These look near perfect.

btw, John, I've followed closely your contributions to this thread - that work looks excellent... :applaud:

John W
08-31-2007, 10:42 AM
Thanks.
Actually I finally broke down and purchased foilcal and grill plates from another forum member who had them made up by Kenji.

http://www.audioheritage.org/vbulletin/showthread.php?t=11663

They are very nice, almost perfect reproductions. I don't think the member I bought them from has any left. Plus, he got a speeding ticket on his way to ship off the package negating any profit and probably removing any incentive to bother selling any again. Still, thanks a ton :D

They may still be available from the source.

gerard
08-31-2007, 10:44 AM
Hello John W .

Sorry What do you mean by side of the resistor .
Does the wire has to be on one only side and why ?:blink:

Here is an other pic

Gerard

John W
08-31-2007, 10:50 AM
Current from the battery flows throught the resistor to charge the capacitors. You have it correct, except for the connection on the far right. This one has the battery connected directly to the capacitors, it isn't in series with the resistor. Have a look, the resistor connects from the capacitors to a dead end.

boputnam
08-31-2007, 10:52 AM
Maybe this will help...

gerard
08-31-2007, 11:06 AM
Ok

I will correct it and look at the other Xover .

May be I shall post a new pic of both Xover after so You might be able to check again .

Thank's again .

Gerard

gerard
09-03-2007, 08:24 AM
Hello

Here are the 2 crossover with mod on the two ( the mistake was on both of them ) .

Thank you for comment if anything has to be changed .

Gerard

JBLOG
09-24-2007, 02:26 PM
Are the side panel 1x3 bracings physically attatched (glue,screws) to the front baffle and rear panel? ..or just a snug it?

Additionally, are the 1x3s that brace the mid 'dog-box' attached via screws to the rear panel or to the adjacent vertical rear panel 1x3 bracings.

I have seen a few threads describing wedges to sure up that axis, but nothing describing physical attachment. I would imaging that end-grain glueing to the front and rear panels is not an optimal scenario.

Thanks

richluvsound
09-24-2007, 02:47 PM
Hi Mr Blog,

I screwed through the bottom of the brace into the dog box . I also put a fillet of consruction adhesive around everything that I had joined . Mine is only one solution of many . Good hunting

Rich

JBLOG
09-24-2007, 02:54 PM
Hi Rich,

Did you also screw the dog box brace to the rear panel, thereby 'tying' the front and rear panels together.

richluvsound
09-24-2007, 03:12 PM
the dog brace is screwed to the vertical brace of the rear panel;)

JBLOG
09-24-2007, 03:31 PM
:thmbsup:

Thanks!

Love that veneer!

boputnam
09-24-2007, 03:58 PM
Are the side panel 1x3 bracings physically attatched (glue,screws) to the front baffle and rear panel? ..or just a snug it?:no: - there are no screws through the baffle.

:yes: - there are screws through the back. I have not opened to look, but they are positioned about where I would expect the bracing to be. They are inset 2-3/4" from the outer edge of the cabinet. There is only one screw for each brace on each side (four total).

JBLCanuck
11-28-2008, 10:15 AM
......So I have questions...... :)
I'm looking at Bo's pictures & it appears that the baffle is 1" plywood. The bracing in the back of the cabinet appears to be particle board/mdf??
Is the cabinet itself built in mdf?? Can't tell by the pictures with the insulation inside.
Great pics & great thread!

speakerdave
11-28-2008, 10:17 AM
1" mdf

JBLCanuck
11-28-2008, 11:13 AM
I see....
So upon further inspection of Saeman's pictures...they seem to have a 3/4" Birch baffle & 1" PB sides/back.
In 2008/9...is MDF better than PB for this purpose or is there some other reason to use a particle board?
Thanks for the info. :)

Mr. Widget
11-28-2008, 12:01 PM
In 2008/9...is MDF better than PB for this purpose or is there some other reason to use a particle board? JBL used to use particle board, but by the 80's like most everyone else they switched to MDF.

It would seem that based on this secondhand account of a study comparing cabinet materials, it would make sense to use MDF for the main cabinet and use plywood for the dog house.

http://www.stereo.net.au/forums/showthread.php?t=8796

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