Did I do well?

[Mike F]

After several decades of lusting over all vintage JBL`s, I finally came across a deal I simply could not turn away from.
Please refer to the following links, they will give you some insight as to where I was coming from.

http://www.audioheritage.org/vbullet...y-drivers-quot

and

http://www.audioheritage.org/vbullet...arts&highlight=


It`s been nearly a year since those posts were made but I`ve been busy scanning various classified ads looking for the perfect pair of L-100`s, 4311 or similar.
To be quite honest, I nearly gave up hope on finding anything worthwhile as most of the offerings were in far less than presentable condition and most had at least one tweeter dust cap poked in (what compels people to do that?)
Now I wasnt kidding myself, these speakers are more that 30 years old so naturally there would be some cosmetic issues to contend with but some were in down right awful condition.
Also, the prices that some of these units were commanding were just outrageous.

But this morning, all of that changed... I came across an ad for what appeared to be a very nice pair
of 4425`s! The pictures that were posted were those of the actual units.
I contacted the seller and was on my way to a small town 100 kms away in Ontario. Nothing could have prepared me for what I saw.
If I didnt know better, I`d swear these speaker were manufactured yesterday. Not a scratch, dent, rub, smudge, fingerprint, piece of lint or spec of dust to be see anywhere, including the bottoms!
I was shocked. The seller then tells me "I have some bad news" Uh-oh, here we go, too good to be true, that brought me back down to earth.
You see, in his haste to post the ad, the speakers were not tested and he discovered one of the horns to be non functional. Well thats not so bad, I was pretty sure diaphragms can still be had so he cut me a break on his price to compensate, got them for $500. BTW, they were freshly re-foamed.
So what do you think of that? I never considered owning a pair of those due to several reasons but I just couldnt pass on this deal.
Now I just need to get the horn working and figure out a way to get the speakers off the floor a foot or so. I know aftermarket diaphragms exist but is it possible to source an original?
I cant wait to fire these babies up!
Sorry for the long post but I`m really excited about this aquisition and I`m hoping these speakers will serve me well for a long time to come.

[Titanium Dome]

Others will likely chime in with suggestions on ways to check the condition of that driver, and it could end up being something pretty simple. I'll just say congratulations and best of luck with your "new" JBLs. They should give you much pleasure.

[DavidF]

A JBL 4311, or variant, would give you a perspective of JBL at its core legacy. For that reason you might enjoy them but up to a point. However, you could come to think that there could be more to what JBL sound is all about. I think that the 4425 could be just the right model to “stumble” upon for initiation purposes. Two-way, horn loaded high end, punchy low end response, but much smoother and listenable than 4311 era small format monitors.

[BMWCCA]

Others will likely chime in with suggestions on ways to check the condition of that driver, and it could end up being something pretty simple.

I always vote for a dirty L-pad. Worth a quick look. Just rotate it through its sweep a few times with the volume down, then give it a try. If that doesn't work it's time to swap the bi-radial from one box to the other and see what happens.

[Lee in Montreal]

Good find. For the diaphragm, you'll want to find an original one if you want to match the other horn. Also verify that the refoam was done with an original JBL part. Back to the bad diaphragm, measure its resistance, It is possible the problem is somewhere else. The owner must probably have been given the speakers as he didn't know a horn was dead. It'll be up to your to acertain the speakers' condition.

BTW There was a set of 4425 for $300 on Montreal's Kijiji last week. I am tempted to think it is the same one and it got flipped.

[berf]

You did well to skip over the L100's or 4311's. They weren't made to be flat or accurate and their current price far exceeds their value. The 4425's were what you wanted all along, you just didn't know it at the time.

[Robh3606]

Also verify that the refoam was done with an original JBL part.

???? There is no original part short of a complete recone. JBL doesn't sell foam surrounds. Just complete recone kits.

Rob

[Lee in Montreal]

Actually, you are correct. A refoamed JBL driver automatically involves aftermarket surrounds. My bad.

Lee

[Mike F]

I looked in to getting an original replacement diaphragm today, $252.00 plus taxes
Looks like I`ll have to settle on an aftermarket unit. They seem to be in the $40.00 region so I`ll probably
get two.
There are bound to be performance differences between OEM and aftermarket units so it seems logical to install two new identical diaphragms even though the aftermarket units are probably of inferior quality.

The other thing I didnt anticipate is what to use as stands? Now thats going to be a challenge!

[1audiohack]

If your going to go the aftermarket route at least buy the Radians, they at least follow the frequency curve of the JBL diaphragms although not as smoothly.

We shot a cheap new off shore 2425 diaphragm across the plane wave tube for fun and it's performance was absolutely horrible. If they were free they would still be a ripoff!

Have you determined that it actually has a failed diaphragm?

[Mike F]

If your going to go the aftermarket route at least buy the Radians, they at least follow the frequency curve of the JBL diaphragms although not as smoothly.

We shot a cheap new off shore 2425 diaphragm across the plane wave tube for fun and it's performance was absolutely horrible. If they were free they would still be a ripoff!

Have you determined that it actually has a failed diaphragm?

Oh no,that`s not what I wanted to hear! I went ahead and ordered 2 aftermarket diaphragms.
I`ll do an FFT analysis on both types and see what the differences are.

[Robh3606]

You have to watch the aftermarket diaphrams you never what you are going to get. Attached is a run with a pair of JBL's vs. an aftermarket. Did this what 5 years ago based on the above post things are not getting better.

Rob

[Lee in Montreal]

Oh no,that`s not what I wanted to hear! I went ahead and ordered 2 aftermarket diaphragms.

For the diaphragm, you'll want to find an original one if you want to match the other horn.

Two wrong diaphragms doesn't make one right combination

[DavidF]

"...Have you determined that it actually has a failed diaphragm?..."

Yes, yes. Can't rule this out before spending more bucks. Especially as you described the care given these speakers. Those Lpads in the crossovers, for instance. Built up grunge on the connectors.

[Mike F]

Two wrong diaphragms doesn't make one right combination

Indeed.
My reasoning is to have a matched pair. I`not about to spend $300 on a single OEM.
If I dont like them, I could go the Radian way.
Love your avatar btw