Should I buy a pair of JBL 4343?

[Kai]

New to this forum and new to this subject ...

It must be close to 40 years ago that I listened to a pair of JBL studio monitors, very large ones with two 15' woofers - which effortless and powerful sound left an impression lasting till today. Now I'm in the position to obtain a pair of studio monitors, I've been offered a pair of JBL 4343B at what seems to me a reasonable price (€2000).

Since I never heard these speakers, my first question is concerning the sound. Currently I own a pair of Tannoy D700, so I'm used to horn driven speakers - do I have to expect colorations to some extent? For professional reasons I have to listen to classical music from time to time.
The seller is quite far away from me, I'm in Germany, he in Spain, so I can't have a listen myself.

This leads to the second point, which questions should I ask the seller? He claims, that the speakers are fully original, the surroundings of the bass and midrange drivers are undamaged and that he is the first, original owner. What else is important, what are the general weak points of JBL 4343?

The seller claims that all speakers are AlNiCo-drivers. The serial-no. is 001423 (and 001424, I assume) - were all drivers still AlNiCo then? In this context, I have read somewhere on the net these drivers should / could be re-magnetized - is this true?

A lot of questions, so I save the other ones for a later post ...

Thanks in advance for your help in advance,
Kai

[martin_wu99]

New to this forum and new to this subject ...

It must be close to 40 years ago that I listened to a pair of JBL studio monitors, very large ones with two 15' woofers - which effortless and powerful sound left an impression lasting till today. Now I'm in the position to obtain a pair of studio monitors, I've been offered a pair of JBL 4343B at what seems to me a reasonable price (€2000).

Since I never heard these speakers, my first question is concerning the sound. Currently I own a pair of Tannoy D700, so I'm used to horn driven speakers - do I have to expect colorations to some extent? For professional reasons I have to listen to classical music from time to time.
The seller is quite far away from me, I'm in Germany, he in Spain, so I can't have a listen myself.

This leads to the second point, which questions should I ask the seller? He claims, that the speakers are fully original, the surroundings of the bass and midrange drivers are undamaged and that he is the first, original owner. What else is important, what are the general weak points of JBL 4343?

The seller claims that all speakers are AlNiCo-drivers. The serial-no. is 001423 (and 001424, I assume) - were all drivers still AlNiCo then? In this context, I have read somewhere on the net these drivers should / could be re-magnetized - is this true?

A lot of questions, so I save the other ones for a later post ...

Thanks in advance for your help in advance,
Kai

1.get it for this price
2.4343b is much better than your Tannoy D700 in every aspect
3.ask the seller if the surrond is originl,after so many years the surronds must be broken,what surronds he has replaced?
4.4343b has 2231H and 2121H which are not AlNiCo-drivers,2420 and 2405 are AlNiCo-drivers, re-magnetized need specific equipment and is not necessary

[Kai]

1.get it for this price
2.4343b is much better than your Tannoy D700 in every aspect
3.ask the seller if the surrond is originl,after so many years the surronds must be broken,what surronds he has replaced?
4.4343b has 2231H and 2121H which are not AlNiCo-drivers,2420 and 2405 are AlNiCo-drivers, re-magnetized need specific equipment and is not necessary

Thanks so much for your response. The current owner swears that nothing has been replaced. May be you can confirm / deny this on the pictures?
If the surroundings are original and might be replaced soon: can this be done in original quality? What amount do I have to expect?

Did 4343B never ever had AlNiCo low- and midrange drivers? Possibly this was just a misunderstanding in the way that all what was ever available in AlNiCo is there.

Thanks again.

[martin_wu99]

Thanks so much for your response. The current owner swears that nothing has been replaced. May be you can confirm / deny this on the pictures?
If the surroundings are original and might be replaced soon: can this be done in original quality? What amount do I have to expect?

Did 4343B never ever had AlNiCo low- and midrange drivers? Possibly this was just a misunderstanding in the way that all what was ever available in AlNiCo is there.

Thanks again.

You are wellcome.
Apparently the seller is no so honest,the cones and surrondings are too new to be true and someone who replaced it with no skills
Tthere are original JBL kits for cones and surroundings and many other good qulity surroudings for 2231 and 2235.
Yes,4343B never ever had AlNiCo low- and midrange drivers but 4343 had,that is the main distinction between 4343 and 4343B
Pay special attention!

[speakerdave]

I'm not so sure there is a "skills" problem with those woofer cones. Whether original 2231h or 2235 replacement kits, it could be the shadow and highlights in those low res photos making the surrounds and the glue lines on the domes look shaky. Either way, as long as those 10" midbasses are original or authentic recones, for me the deal would be a go at that price. Any problems with the woofers can be remedied.

[RMC]

Hi Kai,

An afterthought, and a possible money saving idea for you. I generally try to think about value for my colleague's money instead of just easily throwing good money at a problem.

If, and only if, the cones on the the woofer and mid are actually original JBL stuff and in good condition, it may be worth it to have these re-surrounded properly only (not reconed $), thereby saving a good amount of cash which you may well need anyway for the high frequency devices as mentioned by another and crossovers... That should be done with driver model specific material instead of simple generic surrounds to increase the chances of driver similar performance afterwards. This idea is based on the following.

D.B. Keele has indicated, in his sixth-order LF alignment paper, "The relative insensitivity of vented-box frequency response and cutoff frequency to changes in the driver's suspension compliance..." (1974, P. 354).

Ten years later, Electro-voice reaffirmed that idea in these terms: "... Thiele's model shows that system performance is relatively insensitive to variations in certain speaker characteristics, e.g. suspension compliance." (E-V, Pro Sound Facts, No. 7, Oct. 1984, P. 1).

What this means in practice is that even if new surrounds aren't perfectly identical, within limits, to original ones in terms of compliance (assuming spider is good), then the chances of noticing a difference or deterioration of sound from original ones would be slim. This may be worth a try.

One fellow here even tried it on JBL 15" woofers with Butyl Rubber surrounds (there's a thread here on this) and he was delighted. He added he could not hear the difference from before and after. Food for thought...

Regards,

Richard

[ivica]

Hi Kai,

An afterthought, and a possible money saving idea for you. I generally try to think about value for my colleague's money instead of just easily throwing good money at a problem.

If, and only if, the cones on the the woofer and mid are actually original JBL stuff and in good condition, it may be worth it to have these re-surrounded properly only (not reconed $), thereby saving a good amount of cash which you may well need anyway for the high frequency devices as mentioned by another and crossovers... That should be done with driver model specific material instead of simple generic surrounds to increase the chances of driver similar performance afterwards. This idea is based on the following.

D.B. Keele has indicated, in his sixth-order LF alignment paper, "The relative insensitivity of vented-box frequency response and cutoff frequency to changes in the driver's suspension compliance..." (1974, P. 354).

Ten years later, Electro-voice reaffirmed that idea in these terms: "... Thiele's model shows that system performance is relatively insensitive to variations in certain speaker characteristics, e.g. suspension compliance." (E-V, Pro Sound Facts, No. 7, Oct. 1984, P. 1).

What this means in practice is that even if new surrounds aren't perfectly identical, within limits, to original ones in terms of compliance (assuming spider is good), then the chances of noticing a difference or deterioration of sound from original ones would be slim. This may be worth a try.

One fellow here even tried it on JBL 15" woofers with Butyl Rubber surrounds (there's a thread here on this) and he was delighted. He added he could not hear the difference from before and after. Food for thought...

Regards,

Richard

Hi Kai,

I think this is good suggestion.
Regards
Ivica

[RMC]

Hi Kai,

Re: "...to check the drivers - is this possible from the front or do I have to unscrew the baffle?
The cone drivers you can remove from the front. As for the compression driver and tweeter you may very well have to remove the top front panel since there are separate chambers for 10" and 15" drivers, so there seems to be no access to high frequency drivers through a mid or woofer hole for example because of those separate chambers (see 4343b data sheet, enclosure section).

RE: "He says that he only could recone the bass drivers with original parts, all other drivers not with original parts, the midrange not all. Is this common sense? And is this the end of the story or has somebody expierence with 3rd party replacements which work equally well?"

This is the cruel reality of purchasing older speakers (1980 or so)... Original parts aren't available forever. And aftermarket parts quality varies from good to bad and ugly... It will work, the issue is how well? Unfortunately, its not written in the sky which is what, though experienced speaker repair people may know more than others about that.

As for aftermarket parts maintaining same specs and performance as original ones, this remains a big question mark. Welcome to the world of older speaker restoration. Regards,

Richard

[RMC]

Hi Kai,

RE: Post # 32

Though some people would like you to believe that speaker restoration (refoam/recone) is only a matter of "experience", its not necessarily the case, far from it. "Experience" appears more like a smoke screen when taken alone...

2 years ago on the web site of a known local Pro shop claiming to be "experienced" in doing nice speaker repairs, they had a picture of a 15" woofer they refoamed, this showed quite similar deficiencies to the 10" driver picture in this thread! Seeing this, I never gave them work. Later they took the picture down...

I was speaking a couple of years ago with an owner of Solen I know since I'm a customer there for 25+ years, regarding who does a nice refoam/recone job because I had a few to do. I mentioned names of known possible places (even authorized JBL and others). Solen did sent numerous speakers outside for repair, to very "experienced" and known shops, because they sell/distribute a LOT of brand name drivers from low to very high-priced items.

Interestingly, he said my shop names with most "experience/expertise" here were the places where the work done for him was the worst quality, that they should know better that, he even added he threw some repaired drivers in the garbage when getting them back, as they couldn't sell them in that condition! Also interesting are the places used for repair.

For refoam/recones, a one-man show shop, guy not even a technician, but rather a guitar player who started by repairing amplified lead guitar/bass guitar cabs, etc. He's conscientious and takes his time to do it right. Refoam turnover time a month! (has other jobs too), but Solen swears his work is top notch...

For electronic repairs, again not one of the major "experienced" shops, but a loner doing this in his home basement shop, he's an electronics technician from airplane avionics repair. He cares and does it right.

Many "experienced" professionnal refoamers/reconers do this by habit, on cruise control, since not rocket science, they go fast (claim 1/2 hr refoam), even rounding corners in order to attack the next jobs waiting. Some videos on the net are revealing. Quite understandable, business has to make money, time is valueable so can't spend too much and refoam work prices are even seen at a flat rate per size. So to be profitable no time to waste, doing it the fastest way. Some don't shim, therefore don't cut the dust cap saving time, when they do cut it many glue a new larger cap to cover their traces (adding mass) and its faster. The frame, cone and/or old surround clean-up is done quickly, sometimes barely, even seen foams glued on front side of cones instead of back side as original since its easier and faster, claiming its the same, then why JBL glued it on back side? That from "experienced" people! Yet, attention to details his important here, since the evil is in the details...

One person here says "I have done many over the years-just need very sharp tools [razor blades, exacto knives] good eyes steady hands, and patience." I certainly agree with the eyes, hands and patience (the latter of which businesses rarely have). As for the list of supplies needed, apart from the refoam kit, that list seems markedly short (shims, alcool, etc.), with all due respect.

My neighbor hired an "experienced" contractor to do a fence, long balcony and a large pool deck. The number of deficiencies on these is high (he had even installed two VERY twisted boards right in the middle of balcony!). Plus elementary mistakes related to ground freezing here in winter (often -20° to -30°C) and thaw (contraction and release, ground moving), which may well damage his pool! An "experienced" contractor living here should do better than that...

Its evident that "experience" isn't THE key to it all. The ASSUMED correlation between years exp. and quality work is very shaky in my book. Experience should rightly bring useful knowledge from having done something before (even by trial/error), but in NO way does it GUARANTEE how well this knowledge will be used nor the quality of work done. Those recurrent "experience" mentions in posts don't really mean much the way they're boasted. Probably not even in the top three or four requirements to get the best job here e.g.: conscientious, meticulous/care, strong desire to help YOU succeed, etc. Once you have such personnal qualities, knowledge from experience will sure help, but if those qualities are not there, then "experience" steers things the cruise control way... Skills can be learned, having the right set of personnal values or the proper mindset is much more difficult to knit.

Hiring someone who's sole or main pretention or asset is experience is a risky investment, more than that is required for great work, as shown above and elsewhere. I have always rejected such candidates, as employees, contractors or project vendors. Simply because it misses the point or hides something else.

So if I were you, I wouldn't give too much weight to this "experience" thing initially, as this can be quite deceptive. First, go for such as above personnal qualities with a set of indirectly related questions to assess the person, make him talk, get his project vision first, etc., if you feel he/she really has what it takes, then consider the experience as a plus. As for the budget question often asked, the bait to make it easier/more profitable for vendor, don't fall into that trap, let HIM put numbers on the table for work you want, then YOU decide if it suits you. Manage the project yourself (budget, work involved, prices quoted, execution time, etc.), business decisions. A budget given up front is fast depleted... Globally, are his interests aligned on yours, the customer? They all claim to be the best, you're job is to cut through the sales pitch... Regards,

Richard

P.S. BTW the best car mechanic I've ever had wasn't the most "experienced" of the dealership, instead he was the most conscientious and cared to do it right time after time, and he did! That's why I kept him.

[grumpy]

Not sure why post #32 was highlighted for reference, but sure, demonstrated proficiency is a big plus.
A 'speakers is speakers' volume shop may not be the best for restorations.

Several persons and businesses have demonstrated quality work and been highlighted in these forums.
Always nice to hear of one nearby (vs shipping and crossing fingers).

[SEAWOLF97]

Though some people would like you to believe that speaker restoration (refoam/recone) is only a matter of "experience", its not necessarily the case, far from it......

Well you covered a lot in that post.

I came to this forum as a FNG abt 12 years ago. Since then have done approx 100 refoams (no recones tho).
Got started as our local "expert shop" rather botched a job on my first JBL's (L26's) . I was unhappy about the sloppy glue all over (owner jokes that they "put the glue on with a firehose") and the wrong dustcap.

Studied the LHF tutorial and was doing so many that on our trip to Asia I stopped at the factory and filled my suitcases with all needed sizes. I have only 1 case where my refoam didn't work out and that was on a driver that I didn't fully check out before starting. It ain't rocket science.

My only trick was starting out on cheap throwaway drivers before graduating to JBL's. And yes, it can take 2 days or so for me to do a pair, but I do it right.

It's a great skill to have in your tools bag, I suggest that you start on something of low value and take your time.

[Triumph Don]

Hi Kai,


One person here says "I have done many over the years-just need very sharp tools [razor blades, exacto knives] good eyes steady hands, and patience." I certainly agree with the eyes, hands and patience (the latter of which businesses rarely have). As for the list of supplies needed, apart from the refoam kit, that list seems markedly short (shims, alcool, etc.), with all due respect.

I don't use shims. Play a constant 30hz tone through the woofer moves the cone. Adjust the cone while glue is drying to center the coil. Works every time [well over 100 now]. With very sharp tools I never have a need to use solvents!

[Ian Mackenzie]

I prefer to let people fight their own battles.

Solen are in receipt of post 33.

[johnlcnm]

Kai, I have the 4333B. They have the ferrite 2235, Alnico 2420, and 2405. Should not need a remag. as Martin said. The woofer is what takes a beating from the thump of a solid state amp. That is apparently what demags. the Alnico magnets of the low frequency drivers. From what I have read it only affects the direct DC connected driver.

[RMC]

RE post # 17

"That all is well" and "I say go for the deal" seems easy to say when you're not the one who has to go through all the work involved AND PAY for it! Regards,

Richard