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David V. Webber
05-18-2009, 09:47 AM
OK . So the P/N D16R2421B ( Aluminum ) and the P/N D16R2425 ( Titanium ) sound different . Aside from which might sound " better "
( whatever that means , ) which one pairs with the JBL LE14A Woofer to yield the " truest " sound in a normal - sized living - room , given an excellent input signal ? And , where does one buy it ?

( Price is not a factor ; I just got a $ 1,200 tax return !! )

David V. Webber

grumpy
05-18-2009, 12:39 PM
Beware... -personal opinions and observations included-

Google "JBL D16R2421" (no "B" suffix on diaphragm P/N) and choose your poison.

JBL published List price as of March 25, 2009, appears to be $284/ea.

It's odd that at least one internet vendor appears to mark up the "list price" and then
charge the published list price and call it a savings... perhaps this includes installation?

At any rate, it's not at all clear. Secondly, you should have this service done at a
JBL Service Center if you want any kind of warranty (and presumably get the
performance that you shelled out for).

http://www.jblproservice.com/service/index.html

David V. Webber
05-18-2009, 08:23 PM
Thank You Mr. Grumpy . OK ; I'll go with the Aluminum ones . [ Strange that aluminum would be better than " exotic sounding " titanium ! Also , I wonder why a small , pressed piece of metal with a ring around it costs so much ?? ]

The local JBL Repair Shop which has my LE85s is ; " Price Stevenson " in Downingtown , PA . Anyone have any knowledge about them , good or bad ?

David V. Webber

Earl K
05-19-2009, 06:42 AM
[ Strange that aluminum would be better than " exotic sounding " titanium ! Also , I wonder why a small , pressed piece of metal with a ring around it costs so much ?? ]

- It wouldn't cost that much ( $ 284.00 ) to make the device ( with a healthy profit ) if the diaphragm was for a current product ( driver ) .
- A goodly portion of that charge is a "premium" implemented to cover the cost of maintaining the old tooling ( as well as the personel "know-how" ) to manufacture these things correctly.
- I call it the "nuisance premium" for legacy systems .
- If one doesn't like it / then one needs to look elsewhere for solutions .

>< cheers :)

David V. Webber
05-19-2009, 07:44 AM
Believe me , I am thrilled that the diaphragms are still available . I loved my " bookshelf speakers " made out of the LE85s and the LE14As . I think the JBL crossover was the LX5 . Anyway , after 40 years or so , I guess the caps were getting old ! I was playing " Any Dream Will Do " from Phil Coulter's " Serenity " album . VERY bright and " tinlky " . Of course , I cranked the Hafler up a bit . POP ! Oh , well ; I couldn't replace the caps anyway , as they are buried in tar , ( I guess to prevent any vibrations . )
I posted a note on this forum asking for the diagram to build new X - Overs . Also mentioned That I'd like to make them into 3 - Ways . ( Perhaps with the Usher 9950s instead of the Ring Radiator . ) Guess what ? That is a " miniature " version of one of Greg Timber's most favorite designs !! SOMEHOW , he got hold of my letter , and sent me the diagram AND all the X - Over parts FREE ; including a pair of MONSTER , heavy - gage 4 mH Air Coils ! I haven't built them yet , as I couldn't afford the diaphragms . ( Just using the LE14s with the Ushers now . Yeah , there is a " dip " between the two , my own guestamate X - Over , but they are useable . )
The diagram he sent is just for the LE14A and the LE85 . I will have to find out how to add the Usher .
My twin brother has a pair of " Studio Monitors " ; 15" , 375 and Ring Radiator . His house is packed with junk , and the roof is leaking over those awsome JBLs . I told him they are collectible , and to cut through the wall if he has to to " rescue " them !

David V. Webber

tomee
05-20-2009, 06:19 AM
David,

What model of bookshelf speaker do you have? Sounds like you've had them for a while and still like them, which is great! We'd love to see a picture of them if you can.

What condition are the woofer surrounds in? If they are the original yellow 'Lansalloy' they most likely need replacing. Even if the original surrounds feel soft, they are too stiff - I have several pairs of these woofers and even the pair with very soft surrounds had a free-air resonance frequency (fs) of over 70Hz. Original JBL spec was closer to 25Hz for these. Replacing the surrounds will drop the fs back to where it should be. Of course the best solution is a complete recone as JBL recommends for all their woofers, but original recone kits are not available so a re-surround is the next best thing. There are aftermarket recone kits, but I have no idea how good these are.

Earl K
05-20-2009, 06:52 AM
Hi tomee,

- Davids' le85s have been broken for sometime now .
- Read this (http://www.audioheritage.org/vbulletin/showthread.php?t=113) for some backgrounding .
- Apparently Davids' twin brother popped the diaphragms back in 2003 .:(

>< cheers :)

David V. Webber
05-20-2009, 11:33 AM
Yes , I had the JBL shop in Downingtown , PA re - foam them a couple of years ago . JBL , ( at least in the 70s , ) had a design - book showing how to build - your - own using JBL components . Since the Mid - Range , ( also High , in this case , ) is nod dependen on cabinet volume , I wanted
the " best " Mid / high I could pair with a 14" Woofer . ( I had a pair of DIY
bookshelves , and one set was exactly 14" . [ Yes , a " 14 " woofer can fit in a cabinet with 3/4" material , and still have the OD in that direction exactly 14" !! ] Luckily , JBL had a crossover , ( the LX5 ) which paired the 14" with the LE85 ; ( a non - standard pairing . ) These speakers were
originally used on their sides , with the LE85s to the outside . Now , in my bedroom , they stand on their " bottoms " . Inside dimensions are 22" High , and 12 1/2" wide and deep . Outside dimensions are 23 1/2" High , 14"Wide and 13 1/2" Deep . Port is 4 1/4" Diam. and 7 1/2" long . Dad used to run the Laboratory for the DuPont Plastics Department . So , the nice
foks in the DuPont Shop cut me a pair of DuPont " Delrin " ports ! Distance from the center of the Woofer to the center of the port is 11" . I made the boxes , braced with actual 2" x 4" s . I had a " pro " cover them with Brazillian Rosewood ; ( the REAL stuff , now illegal ! ) The grills are frames which press in snugly , with a coarse - weave red / brown / black color cloth . I think they cross - over at 500 Hz . So , except for the very lowest octaves , there are no electronic components in the signal - path .
Back then , I used to haul them to " Hi Fi " stores and " blow - away " all
the junk they had for sale . Perhaps I still could ! The LE85s go up to , ( I think , ) 15KHz or 17KHz . So , I'm thinking of adding the USHER 9950
Tweets , which are flat up to around 25 KHx with fabulous dispersion . I don't know if this would be wise or not . There is JUST BARELY room , without cutting any component - edges .
We do have a nice digital camera here , So I could take photos . I don't know how to post photos here , but I DO have a photo - site :
http://DaveSail.SmugMug.Com Already there , are a pair of " computer " speakers I made as our new Computer has a " wide - screen " format and can play DVDs . Good for U - Tube / Susan Boyle , etc. !

David

David V. Webber
05-20-2009, 12:44 PM
I'm sory ! The " SmugMug " site shows my " U - PEEs "
not my new " Computer Speakers " . The " U - PEES " are in the Living Room as sort of a minimal " L + R " Home - Theater sound system . I'll have to post the actual " Computer Speakers " . David