JBL 476be/435be

[subwoof]

tell me about it....my shop is full of horns that have been drilled to accept both sizes. some of the 1.5" large horns have fiberglass real close to where the holes need to be so it's an engineering challenge sometimes.

And who at JBL was smoking WHAT when they gave a 1.5" driver ( 2450SL ) the same number as a 2" driver ( 2450 ).

But the snout can be removed from the 2450 and it becomes a 1.5" driver with NO mounting holes that match the horns. Another fun time when I bought 12 of them from a theme park for 50 bux each.

anyways.

but a set of 'plassed 2435Be's on the 2352 horns sound very very nice with little EQ or effort.

[HCSGuy]

but a set of 'plassed 2435Be's on the 2352 horns sound very very nice with little EQ or effort.

That's good to hear - I've got a pair of 2352's waiting for me to build into something.

[4313B]

Can I get Be aquaplas diaphragm for JBL 2450SL or 2451SL drivers!
I think they have 82,5mm bolt circle like JBL 2435hpl. how much does this drivers cost?
did you sell the pair of JBL 476Be drivers you have for sale for few month ago?


Thanks
Ari

Here's the link to driver prices. Transducer List.pdf

Note that the Pro version of the 435BE, the 2435HPL runs $2,798 a pair. I think you can get them off eBay for something like $20 though. They're pretty worthless. And extremely fragile! Don't bump them or let them come in contact with each other or the neo mags will rip the top plates loose from their super glue bonds. Then you'll have a $20 paperweight. They're very nice sounding but they aren't your dad's LE85's. They are meant to be bolted into a system and left there. They don't take well to lots of handling. Early versions suffered surround creep due to the manufacturing process. Later versions had that issue fixed. Mexico still isn't certified to make them. I guess they're kind of tough to make correctly. In fact, Mexico so far has only been certified to make three driver models. Three... That could be a problem...

I haven't decided yet whether or not I am going to sell my personal pair of 476BE's. They were awfully difficult to obtain and I might use them for something someday.

[hlaari]

I haven't decided yet whether or not I am going to sell my personal pair of 476BE's. They were awfully difficult to obtain and I might use them for something someday.[/QUOTE]



I have this drivers in my speakers JBL 2254j/2251j/2435hpl and 045Be
This is hornloded speakers with this crossover point 300Hz/700Hz/10kHz



regards
Ari

[Rudy Kleimann]

That's good to hear - I've got a pair of 2352's waiting for me to build into something.

Yeah, those were MY horns! I thought by now they'd be making music! What happened?

[HCSGuy]

Sorry, Rudy, no good excuses. Yes it's true, supermodels have been throwing themselves at me to keep me from building the speakers. It's also true that tens of billions of dollars have come my way and I continue my path towards world domination. But now that Obama's had his birthday and I no longer have the stress of figuring out what to buy him (I gave him a $10mil gift card to the Blackberry App store), I should have some time this month to build something. The 2352 horns have the larger bolt circle and won't bolt to a 2435 or 2452. I don't like to drill things, so I my current thinking is 2447's with Be diaphragms on the 2352 and either ME150H's or one of the woofers I got from Giskard. I'm hoping the Be diaphragm will keep me from having to use a tweeter. Any woofer recommendations?

[pos]

ME150H and... 1500AL?
I will be curious to hear your comments on hox they compare!

[Rudy Kleimann]

The 2430, 2431, 2432, 2435 models all have the same mechanical frame and bolt pattern that WILL interchange with the AQUAPLASSED first gen 4" coil drivers ( 2450SL, 2450SL-a ) but not with the 2451.

Why JBL dances around with these different dia's I'll never know.

I've been trying to obtain/verify the bolt circle for the 243x drivers to see what they'll fit of mine. The 2431 is used on "standard" PT-FxxHF horns in the AM62xx-series, but the 2432 is used on "-1" variants of the PT-FxxHF horns in the AM72xx-series. Nowhere can I find the bolt circle dimension on the public side of the jblproservice website -and I've looked everywhere. Are the bolt circles the same? What diameter? What is the difference in these horns?

What gives? I can't recall ever seeing a picture of a 2431. From the pictures I have seen of the 2435 and 2432, they look different in a few ways, namely the 2432 looks like it has a bit of a '"snout" on the exit side compared to the 2435. I haven't seen a good head-on shot of the flange side of the 2432 to even try to scale.

AFAIK the 2431 is Al, the 2432 is Ti, and the 2435 is bE (and delicate and too expensive these days).

Trying to find a high-power driver that I can use in place of 2447 to get away without a UHF on top for high-Q PA sound. I don't want to buy something only to find I can't use it on my 235x or 238x horns, or that the marriage sounds like hell. 2432 seems to fill the bill.

What say you, Subwoof? Anybody?

[Robh3606]

Hello Rudy

This doesn't answer your question directly but I find this to be a really useful page. A 2435/2431 has the same mounting pattern as a 2452. The 2432?? I have been curious as well. I am thinking that the longer snout may be a new and improved phase plug over the 2430/31/35 drivers.

http://www.jblproservice.com/navigat...%20Models.html

Rob

[Rudy Kleimann]

Hello Rudy
This doesn't answer your question directly but I find this to be a really useful page. A 2435/2431 has the same mounting pattern as a 2452. The 2432?? I have been curious as well. I am thinking that the longer snout may be a new and improved phase plug over the 2430/31/35 drivers.

http://www.jblproservice.com/navigat...%20Models.html

Rob

Yes,... years ago already (sigh) Wish it was there, but the 3" drivers are NFS, so...

Thanks Rob, but deeper sleuthing around all over the site has only produced the hint of "-1" variants of PT-F horns going with the 2432H... so, by deduction, I'm reasonably certain the bolt pattern is different. Why is yet TBD.

RE: the longer snout, there's something to it, but it is odd, considering that the trend since the 2447 has been ever-shorter exit throats on the drivers- every new model has been shorter, to the point that the 2435 and 2452 have been referred to as "Throatless". It's all about the lower-distortion "rapid flare" philosophy with more of a direct line of sight from the diaphragm to the desired coverage area, beginning with the 1.5" exit 2447 driver and "Optimized Aperture" (Marketing "Hoopla" for rapid flare) horns to go with them, the brainchild of the then-freshly recruited Engineer JBL hired away from Renkus-Heinz.

That's why the bolt circle changed from 4" to 4-1/2" -to keep horn throat/driver mismatches from occurring. that, and to provide extra bolt or stud/nut clearance for the 'rapid flare' rate horns...

So you might have something to that. I wonder if the PT-fxxHF-1 horns are shorter by the same amount as the longer 2432 "snout", with a correspondingly larger throat size so the flare contour is really the same, only the driver/horn parting line is further down the path?

[pos]

I thought the -1 PT variants were 1" horns?...

Imporved phase plug on the 2432 ?
If that is the case that would be interesting to see if 2435 Be diaphragms would fit in this 2432?

edit: Hmmm the diaphragm structure looks similar to the 2407 or 2416...

[Rudy Kleimann]

I thought the -1 PT variants were 1" horns?...

Imporved phase plug on the 2432 ?
If that is the case that would be interesting to see if 2435 Be diaphragms would fit in this 2432?

edit: Hmmm the diaphragm structure looks similar to the 2407 or 2416...

The 2432H drivers, whatever their exit size and mounting bolt circle measurements are, come exclusively on the AM7xxx series speaker sytems, and all on "-1" variants of the PT-FxxHF(-1) horns. 2431H come on the "Standard" "non -1" PT-FxxHF horns

Rob's guessing there is an improved phase plug on the 2432- I just said there appears to be an extension, a "snout" on the driver, a la 2446 vs 2447, or 2450 vs 2451. In these cases, the snout was nothing more than a section af an exponential horn to transition from the new 1-1/2" exit to the standard 2" horns they were built to fit.

I am guessing the snout on the 2432 may be serving a similar purpose, but a guess is all I have. It could be larger than 1.5", or not.

You have a 2432 driver in your possession? Why don't you enlighten us all here with some good pics and accurate measurements. It's a golden opportunity to help us all out here with a valuable contribution to the forum. I know I would do it if I had the driver!

First off, what is the mounting bolt circle diameter? that is the question of the day.

Shine a bright light at various angles into the screen and have a look down there to see if a phase plug is lurking up close to the screen inside the extension. Pulling the gasket/screen and measuring the exit up top would be next. I have a feeling you'll find the snout is held on to the driver itself by 4 screws, a la 2450H/J 2" adapter. Then you could pull the snout and measure the snout thickness and it's entry and exit holes to see what the flare rate is. It could be that the 2432 has a slower flare rate, ending at 1.5" at the part you see and somewhat smaller at the driver exit itself. Take pictures with a good ruler across the openings. better yet, a precision caliper good to .001".

Check how far below the face of the driver the phase plug ends. A machinists' measuring tools (or machinist friend with them) would be in order right now.

Inquiring minds want to know...

[pos]

Sorry I don't have that driver, the photo comes from ebay

[herve M]

and Here ?

http://www.audioheritage.org/vbullet...ighlight=2432h

[Rudy Kleimann]

But the snout can be removed from the 2450 and it becomes a 1.5" driver with NO mounting holes that match the horns.

You mean. like this?

http://rover.ebay.com/rover/0/e11051...TQ%3AUS%3A1123

Auction number 300453848455 in case the above link is invalid.

Talk about timing!

This came up from my saved searches last night. I already pointed out that these are not really 2451's as they are, but look to be 2450's with the wrong labels. Stuinning, actually, considering they are consecutive serial numbers and in mint shape otherwise, according to the seller. Seller deals in high-end gear, so this is a real mystery. I'm trying to get him to pull the 'snouts' off now and verify a 4-1/2" mountig bolt circle exists under them.