JBL does not supply surrounds; it's all aftermarket.Originally Posted by Evets
The presumption is that if the foam is shot, the spider's tired, too, or aged, so full recone is the only factory-supported refurb option.
JBL does not supply surrounds; it's all aftermarket.
The presumption is that if the foam is shot, the spider's tired, too, or aged, so full recone is the only factory-supported refurb option.
Thank you, Zilch.
For 5 bills just buy a set of OG L-100s or 4311s
Paragon
Olympus
L-100's
4311's
If the economics don't matter that much, and what you want is a "project," DIY speakers using L100 components (or some of them, at least,) would be a worthy pursuit. The answer to the "Why bother" question is you then have the potential of coming out with something actually listenable when complete. Here's my suggestion(s):
1) A cabinet sized and tuned to have 123A-1 play well. Closed box seems to be a valid, if not optimum, approach (EBP=48). BB6P suggests 3.3 cuft. (below, blue,) but I'm liking a bit smaller, 2.8 cuft. (orchid,) with heavy fill, to keep the excursion within spec. Bass response (-10 dB) goes down to ~27 Hz with that, i.e., quite good.
See here for more:
http://audioheritage.org/vbulletin/s...ad.php?t=12036
2) Mirror-imaged offset vertical-in-line driver alignment like L100T:
http://manuals.harman.com/JBL/HOM/Te...L100t%20ts.pdf
For horizontal, I'd look to 4412(A) as a model, though it might take some measurement and testing to optimize.
http://www.jblproservice.com/pdf/Stu...es/4412ALR.pdf
Reminder: One side only shown in the pdfs. You want to build a mirror-image pair.
3) 035tiA tweeter in lieu of LE20/25. That'll get you some decent HF, which stock L100s can't deliver.
4) A crossover designed to tame LE-5 "forward" response.
[I mentioned mirror imaging, right?]
Superbee,
I appreciate the practical and sensible advice. What does "OG" mean? Original? If I can find a good enough deal I may just do that. However...
...after all the threads I've been reading and advice I've received, I'm now leaning towards a pair of 4412s for starters. I'm worried that the JBL bug that many of you seem to have has bit me as well. I've even been looking into the 4345 as an expensive, long term project for the period after the 4412 (and/or L100T project) is completed.
Zilch,
Thank you for the additional advice and the corresponding links. As I mentioned above, I'll probably start by buying or DIYing a pair of 4412s, but if I change my find or find a good deal on L100 components I will certainly follow your advice. I found a new Dennis Murphy designed crossover for the L100s on another forum that might be fun to try.
Ideally, the project will involve building new boxes to the original specs and updating the original crossovers with newer and hopefully better caps and the like, but I'm flexible and open. This will probably be my first of multiple JBL adventures.
Thanks again.
You're doomed!
Widget
Follow the link in the first post here:
http://audioheritage.org/vbulletin/s...ad.php?t=10603
I cannot post what I said when I saw they weren't mirror-imaged.
It would have been SO easy....
Probably, and it wouldn't be the first time!
Yes Zilch, I saw that post as well in the midst of all my reading the past few days and I thought the same thing. Fortunately for me, I have already built several DIY speakers that other people have designed so I'm well-versed in making square boxes with mirrored arrays of round holes. I've even developed a moderate level of soldering skill, especially since I started using the super-expensive Cardas solder.
The pair of 4412s currently on ebay are not mirror imaged so I'm thinking that if I can get them for a decent price I will build new cabinets so that they are mirror imaged. If the price gets too high I'll simply wait for something else. I will adapt the project to whatever ebay, craigslist, recycler, and the like provide.
I made these:
They are very flat in response and a little dry, just like white wine. I had the woofers for years ( they needed refoaming of course) and I gathered the crossovers and other drivers from ePay. Not counting the woofers I already had I spent about 300 dollars on the project, + 80 getting the woofers repaired.
I ended up with a great studio monitor and saved a little dough. I also get the satisfaction of making them myself. I changed the design a bit by having the baffle board overlap the sides instead of being set in and the port was seamlessly blended into the baffleboard.
I like 'em a lot. They sound like my AKG headphones in that the bass and treble are balanced and not overbearing. The 4411 had a great crossover network with a third order HF network (with a zobel), a great 2nd order network for the MR with (IMHO) proper attenuation networks, and even bypass caps on the woofer capacitors. This network was my favorite of all these 12 inch monitors and I thought it was a key to the sound.
Uh-Oh. None of the above are shielded, if that is required with your TV monitor. This may change your plans.
DavidF.
A standard D123 sounds pretty good in that size cabinet as oppossed to the white one. It's livelyer and you can cross it higher. It's more efficient, you can still use that midrange it's not as efficient but you can cut it in and run them together till you bring the tweeter in never loved that tweeter maybe 066 or someone elses high efficiency tweeter. You get a lot more of a "JBL" sound than jbl ever put in a small box. I've got L100's something a little bigger than L100's built around the same components except for a white D130 and som heathkits that are 100's with green woofers and no mid. I used to (early 70's) sell jbl systems in knock off cabinents encluding just a 123 and a le20 against an L100 they even used to build sub woofers around the 123 (stuck it in what looked like a long wooden wistle) its the only yhing that can sound like a big jbl system in a small box. I've put a standard 123 in a 100 cabinet but it likes a larger vent. Yiu can make it sound just about like the L100 woofer by really stuffing the box if that is what you want. If you like live concerts (the kind played on large pa systems) this is as close as you can come to bringing it home in a small box. It will play many times louder than the L100. Jbl's D131 won't have any bass at all if you put it in a small box. Thiss woofer should be easier to find. I don't think it's considered highly desirable. Just my opinion.
I'm having difficulty envisioning that sub. Can you post a pic or a sketch?
it was called an air coupler. It was maybe 8 feet long (I don't know the exact deminsions and I don't know if they were critical or not. I wouldn't think they were critical because you wouldn't want it to play one note like a pipe but it might be critical I'm not sure) It was about 16 inches wide and 4 or 5 inches thick. their was a port the full width of it about 6 inches from one end and about 5 inches across. On the opposit side from the port begining just a couple inches past the port the D123 mounted, magnet out. It originated before stereo and like other large speakers became less popular after stereo. I'm not sure if it was known that frequencys below a certain point were non directional or not. I Don't remrmber how it sounded to much but we mostly sold 030 and 001 systems in C40 and I think it was C34 cabinets and they might not go that deep but when thats what you are used to an LE15A with a passive radiator was so that you could hardly stand to listen to it unless it was an hour past closing yhe bag was half empty and the knob on the c26 hooked up to the 2105 was mostly up, and the dead were playing then the s8r's in the store sounded really good
but otherwise the passive radiator sounded sloppy. Most of what you se at concerts are some sort of a D130 equivuilant the le15 types are mostly there for base. If they don't try to straight from an le15A (I'm sorry I never learned the 4 digit numbers I didn't even know there was a D120 till I read it hear the other day to us they were D131) to a 375 in a stadium why would I want to make that jump in my living room. I'm guessing you can make a good subwoofer around that speaker but in the home That's all. My friend added 6 feet and passive radiators to his parragon and in went a lot deeper but it got sloppy. Anyway I've always been going to try that aircoupler (in '73 when people I worked for took over the Hi Fidelity shop in sacramento there were several just laying around. Anyone read about the driver I described elsware. I've always wondered if they were made just for that install or if they existed at one time.
I'm resurrecting this post briefly to provide a conclusion of sorts. I have purchased a pair of 4412 monitors that are in need of a refoam. I originally planned to refoam the woofers myself with the aid of Rick Cobb's kit and Bo Putnam's "how-to" thread, but have ultimately decided to have Edgewound do that part of the restoration as he is highly recommended by so many members of this forum. As handy as I am, I can't see myself doing as good a job as a certified JBL repair tech with 18 years (?) experience and plenty of recommendations from people in the know. In the meantime, I'll touch up the walnut cabinet (iron out a couple of indentations, touch up a scratch or two, and give the veneer a good oiling.
So that's were this thread and all the advice it contains has led so far. Of course, I still have plans for at least three more JBL acquisitions/projects, including a pair of 4313Bs, a DIY center channel to complement whichever monitors wind up in the HT rig, and a DIY 4343. Thanks again.
-Steve
P.S. And yes, I did acquire a mirror imaged pair.
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