Is it sacrelege? Am I evil? (long) - 4343 xover mods

[4343mod]

Bump!

[Lancer]

Yes... It is possible...

Replace your drivers having foam surrounds with a 1500FE, ME150HS, or 1500AL. None go as deep as the 2231 or 2235 but they don't rot as fast either. EQ is the best bet to fill in the very bottom end when using those drivers. The LE14H-3 is the only driver I can think of right now besides the W1500H that can go real deep. The W1500H is probably not a great replacement driver for the large format 4-ways... well, on second thought, it might actually work with a 2122 and a lower crossover frequency...

[ogmios]

I just got a pair of 4343 given to me. I've refoamed the 2121's sucessfully, they sound great. But the 2231's are weird. One is blown, but seems to be original cone. I know the baskets are original 2231, but the other 15" that still works has been reconed and I like it. I need help figuring out what it was reconed with.

Can anyone tell me which cone kit has a soft felt dust cap, and paper surrounds. The original 2231 I think has a hard dust cap and foam surround.

I love the subtle, gut wrenching thing it does, and I want to recone the bad 2231 as whatever the other one is.

My guess is 2225h, but does that have a soft dust cap?

Thanks, wonderful site, been lurking a few months.

[Earl K]

Hi

(a) Recone your 2231s' as 2235s'. They'll give you the very best VLF from your 2231 frames . Yes they have foam surrounds, but as you said, you're experienced in replacing these things .

OTOH :
(b) If you truly believe that a speaker like the 2225 will give you the bass you like , then buy a pair on eBay ( this will cost about the same as a single 2225h recone ). This will be a less expensive education if it doesn't work out .
- The 2225 has a free air resonance set to one octave higher than the 2235 ( 40 hz versus 20 hz ) .

(c) Pics of your mystery speaker would help (some) the identification ( an electrical anlysis of its' TS parameters would be the best ) .
- The 2225 has a hard paper dust cap and the cone has many ribs ( just like the 2231 ).
- You may have some aftermarket recone kit of unknown origin .
- Look for any printed markings on the underside of the black cone. They'll help the reconers here identify the recone kit .
- It is also possible the recone kit you have is a 2205 or some generic version of it . With a stated free air resonance 1/2 way between the 2225 & the 2235 ( 30 hz ), it may be creating decent enough VLF . This kit is no longer available . ( BTW ; The 2205H looked just like a 2225H ).

Recap > go with point "A" .

[ogmios]

Big Thanks Earl. I'll go with the 2235 recone. I hope it's still available somewhere as soon as I have some cash.

I will try to take a picture of it if you are interested. I just saw a pair of 2231A on ebay that had white cones?!?!? I'll get a pic of both tonight after work. I don't really have electric parameters other than resistance.

I guess it's possible they were both reconed. The original owner is in the family, so I know that he had jbl do it, if he had them worked on.

Unfortunately I can't ask as the poor guy's is in a vegitative state, and the previous owner who got them from this guy doesn't know anything about them, he keeps calling them "Fisher"s LOL.

[ogmios]

I definitely don't want "higher" resonance. This baby is LOOOW and I definitely don't want to mess that up.

They must not be 2225 recones if the dust cap was solid.

[Tom Loizeaux]

I agree that you should re-cone the 2231 with a 2235H cone. You'll love the sound and it will deliver what has made the 4343 a great speaker. Once the re-cone has broken in, compare it to your other 15. You will probably want to re-cone it with a 2235 cone at some point.
Other then carefully using "upgrades" for the 4343, its very difficult to change componants, or anything in the crossover, and get performance that equals, let alone exceeds, the original.
Get your 4343s restored and listen to them for a while.

Tom

[speakerdave]

I just got a pair of 4343 given to me . . . . Thanks, wonderful site, been lurking a few months.

Welcome to the forum, and please stick around so some of that can rub off.

David

[LE15-Thumper]

Yes... It is possible...

Replace your drivers having foam surrounds with a 1500FE, ME150HS, or 1500AL. None go as deep as the 2231 or 2235 but they don't rot as fast either. EQ is the best bet to fill in the very bottom end when using those drivers. The LE14H-3 is the only driver I can think of right now besides the W1500H that can go real deep. The W1500H is probably not a great replacement driver for the large format 4-ways... well, on second thought, it might actually work with a 2122 and a lower crossover frequency...

Where might a JBL'er find pics and specs on these new Consumer drivers ?
Lotsa info on the pro out there.
I hate to wake up Giskard again !!! I miss that cantankerous walking JBL encyclopeadia.

[Mr. Widget]

I believe they have all been posted here at one time or another.

http://audioheritage.org/vbulletin/s...7&page=1&pp=15

http://www.harman-japan.co.jp/produc...ons/1500al.htm

http://audioheritage.org/vbulletin/s...ead.php?t=6006


This is what I could turn up without trying too hard.

Widget

[4343mod]

Hey folks, well I finally did it. I have been dreaming about this since the JBL DSC280 speaker controller (x/o) came out in the mid 90's. The passive x/o's are sitting on a shelf in the other room, and the 4343's are now being driven by (2) Behringer Ultradrive DCX2496 digital active x/o's in mono into a Rane 100WPC 6 ch. amp and the existing Crown 800WPC 2 ch amp. When the DSC280 came out, it's street price was in the $4000 range with a 20/48 DSP engine. I got these 24/96 boxes which use the Analog Devices SHARK DSP for $260 each shipped. I finally put my telecom relay rack to good use! I just have to find a better place for my preamp.

The final word in inner detail and resolution is lost, but SO MANY other things are right, its a no brainer- the DCX's are pretty awesome. Being able to adjust every driver parameter with a laptop from the listening position is priceless, and more fun than I've had in a long, long time. The 2121's are singing better than ever.

Andrew Bacon

[glen]

Sounds like a sweet setup.

What settings have you arrived at from your listening position tweaking?
Crossoer points?
slopes?
phase shifts?
time delay?

Give us the birds-eye low-down on this caper!

[4343mod]

I just took 1/2 hour to put it all in, and when I hit the post button, it asked me to log in AGAIN and vB lost my post. This has happened before, and I forgot to copy my reply to clipboard BEFORE hitting the post button. Argh!

I'm going to go kick somebody.

PM me if you want to come over and hear it for yourself!

[4313B]

One always has to remember to do a Ctrl-A followed by a Ctrl-C before hitting that post button!

[glen]

... forgot to copy my reply to clipboard BEFORE hitting the post button. Argh!

Some times I'll actually compose my post in another program (notepad, or email) before dropping it in to the reply message body. This also allows me to bounce around on the internet without worrying about closing the "Reply to thread" window by accident.