JBL 2121: what to do?

OK, so quite a few years back, I came across a pair of 4340's [or were they 4343's?] that had their 2121's repaired by an unknown 'repairer', who obviously took a few shortcuts, by using surrounds from somewhere/thing else which were oversized and so the surrounds were cut and rejoined to match the circumference of the frame, BUT, not only but also, the cones were also 'trimmed' back by about a 1/2" to accommodate!
Well, I was quite taken aback by this madness, but to find re-cones for a 2121, as everyone knows only too well, is just impossible these days let alone trying to find two of them.

I should mention, that my mate has these speakers now, and has done a wonderful job of trying to restore them, but we'd really love to find an authentic pair of kits to do these speakers the justice they deserve.
Only problem is, we're in Australia.

I'm open to recommendations....

Can anyone help? Please?

George.

Hi George,

You have two options,

Contact Queensland Speaker repairs and request they obtain an aftermarket recone kit.

You can send them the drivers and they will install the recone kits.

Alternatively you can buy the Jbl 2123 mid driver (on eBay) which is a descendant of the 2121.

The 2123 does not have a foam surround and will therefore not require repairs. It’s also a superior driver subjectively and was used in the 4344mk11 monitor.

With some modifications to the crossover network it will work very well.

If you need assistance pls send me a pm.

Hello Ian,

It's been a very long time since we chatted last. Hope you're good etc?

Yes, QSR was my first thought. I know from past experience that they do most excellent work.
I was even thinking it may be possible to just replace only the cone including a new surround etc and fitting it to the original voice coil, if that helps....
There's a chap here where I am in Melbourne that used to be able to do that sort of work really well, and even myself in years gone by, but it's oh such a fiddly job and I just don't know if he's still active, and I certainly know I'm not up to it anymore.
The boxes currently do have 2123's fitted, but as you say, and has been said in the past http://www.audioheritage.org/vbullet...2121-2122-2123 by Heather James, that some work to the crossover would be necessary, which I think has been done, BUT I was desperately hoping to get these boxes back to being original as possible, but I guess you just can't win them all.
BTW, I'm doing all the research first before I present my findings to my mate that now owns the boxes.
He actually is unaware of my looking into this matter but I thought I'd ask around, and then present the options to him once I had done all the hard yards first.
These JBL's are currently situated in Sydney, but no big deal shipping the 2121's to Brisbane to get the job done properly.
So QSR it may have to be then.

Thanks so much for your most valuable input. It's truly very much appreciated.

Cheers lots,
George.

There are four 2121 on ebay. Not cheap but looks good.

Yep... If you look closely Odd, the two listings seem to use the same photos even tho' they're different sellers.
I feel something's just not right about them, plus the different dustcaps, and look like they may have been re-coned.
.... and those prices are pretty well right up there, hey?
I did find some authentic genuine kits, but I failed to get a response, so I think they maybe sold.
They weren't cheap either. Especially once converted to Aussie $$$$$'s plus postage.
Those ebay ones are around AU$2.5k plus paypal's 4 cents in every dollar. Soon adds up!
Prices escalate pretty quickly this side of the world unfortunately.
I think Ian's response is definitely the way to go.... QSR, but maybe just new cones/surrounds, original voice coils, and keep the original dustcaps.
I'll know more over the next couple of days I guess.

Thanks for your input tho'.

G.

Hello Woofer;

I have a pair of genuine JBL C8R2121 kits mounted in perfect E110 baskets for a project yet unrealized. Only the E110 foil cal makes them not exactly correct.

They wont be inexpensive but less than the ones from Japan that at the very least have incorrect dust caps.

Just add this to your options list.

Barry

I think the repair work needs some validation.

My reason for pointing to QSR is first to contact them and get a qualified opinion on the after market kits?

I looked into this a while ago and it’s possible the after market kits use the same pulp dye stamp at a factory in the USA.

As you say the VC also needs to be checked. You are right there are a few really good people in Melbourne who could do the cone assembly work but they may not be familiar with the aftermarket market kit.

So l this is what l will do.

I will contact QSR first and contact / email a few of the after market suppliers in the USA. I have seen very detailed kits and it’s possible you might be able to get the aftermarket market cone assembly as a part.

The JBL importers have changed hands not long ago and they are based in Melbourne.

I will also talk to them again. A few months ago l was told and given a price on JBL factory 2122 recone kits and a lead time! Yes that’s correct. The thing is l had to insist on them contacting the USA / Mexico and l got an answer. (They will often prefer to blow you off with an aftermarket kit. They really don’t want to know about it.) So it’s possible a factory kit can be obtained but at a higher price).

Unfortunately you are not the only one in this boat so l think it’s worth looking into and l agree an authentic 2121 recone in this instance is the preferred option if you don’t want to go the 2123 route.

I agree it’s unfortunate the 2121 cones have been modified in a prior repair. I don’t think buying expensive 2121 drivers solves the problem.

From the designer perspective the 2122 or the 2123 was the go to answer because the 2121 inverted dust cap had break up modes which impact on its performance subjectively. So historical any questions on a 2121 recone have been treated as an upgrade to the 2122 or 2123 variants.

Give me a few weeks.

Ian

Quote:

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Originally Posted by 1audiohack

Hello Woofer;

I have a pair of genuine JBL C8R2121 kits mounted in perfect E110 baskets for a project yet unrealized. Only the E110 foil cal makes them not exactly correct.

They wont be inexpensive but less than the ones from Japan that at the very least have incorrect dust caps.

Just add this to your options list.

Barry

---

Great option

Thanks again Ian and Barry also. [I'll PM you Barry in a few days for more details...]
I shall be discussing all the options mentioned with the current owner once I get a hold of him shortly.
In the mean time, QSR, I've found out, do have just the cone available and very very cheap: https://qsr.net.au/?s=jbl+2121&post_type=product so I'll give them a call later today.
Things are progressing faster than expected, so give me some time to present all the options to the owner.

George.

UPDATE:

I think the problem has been solved.

Thank you everyone so very much for the input. I'll issue a summary in a week or so regarding the outcome [with pics hopefully].

Ian, I've PM'ed you.

Cheers lots guys,
George.