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In Reply to: RE: Help With Futterman Mono Amps posted by Toto on April 01, 2015 at 09:36:25
Shortly after making and selling this version to a few folks on a custom basis, Julius discovered the use of photoflash caps as output coupling caps on his amplifiers. Around that time (1972) I commissioned a pair of the later model, which he called "H3aa", with about six or eight photoflash caps per chassis, mounted where that one giant can is sitting on your amplifier. Getting rid of that gigantic capacitor in favor of a gaggle of modern much smaller value, much smaller size Panasonics (for one example) will greatly improve the sonics. The big cap has to go, anyway, because of its age. See if you can get George Kaye to look at the amplifiers. He goes back to Julius directly, but I don't know if he's still active.
As of the early 70s, if you wanted a new "Futterman amplifier" you contacted Julius, sent him a deposit, and waited. Eventually, he would call you and in muted tones of an old man he would tell you your amp was ready. Which meant you made an appearance at his workshop (cannot call it a factory) on West 72nd St in NYC, off Broadway, because there was no shipping. Power transformers that Julius made himself would be hanging on a clothesline so the goop that held the windings could dry. Just smelling that smell probably shortened my lifespan. The PT is very critical and not so easy to replace; don't fire those bad boys up until someone competent has serviced them. I used my H3aa's to run two pair of KLH9s, for a glorious sound.
Follow Ups:
H3a was my guess, too, until I found this image in rhinohifi714's gallery that's identified as an H3a.Looking at photos of the H3aa, I now think that the ones in my possession are early, hard-wired versions. Later, more finished looking builds replace the single cap with six smaller ones, but otherwise appear to be very similar.
George Kaye is still active. He's in Brattleboro, VT, and has a site called kayeaudiolabs.com. I also found references elsewhere on the OTL Asylum to a retired NYAL engineer named Ted Hammond, in Croton, NY, who also worked on them. However, health issues may have limited his activities.
Joe
Edits: 04/02/15
but of course I could be wrong. I once owned the model shown by Rhinofi. It is a much earlier amplifier, probably built in the 50s or early 60s that was produced under the "Harvard Electronics" label, when Futterman was more "in business". I think it was rated at 30 or so Watts per channel and was not in the "H3" series. But Rhinofi may be able to prove me wrong by showing a photo with the model number on the chassis. The H3s were all monoblocks, for one thing.EDIT. The internet is a wonderful thing sometimes. I did a quick search and found two facts to modify my post: (1) I am incorrect, not all H3 series amplifiers were monoblocks, and (2) I was correct, the amp in your photo is not an H3a; it is an H3.
Edits: 04/02/15 04/02/15
Yes, I think you're right. The previous photo is a mislabeled H3, mine are H3a's, and the later H3aa replaces the single large cap with six smaller ones.
For anyone who is interested in Futterman history, this website is great:
http://www.audioclassica.de/files/Dokumente/Die-Futterman-Story-2.pdf
The photos are surrounded by German text, but in the back there is an English translation of a description of a visit to Julius's shop in NYC. The author nailed it perfectly. That is exactly as I remember it myself. I was there at least twice. Julius was a sweet and humble man in all ways except one; he fervently believed in the superiority of his design for ESLs or for any high impedance speakers. Such speakers were more plentiful in the 50s and early 60s, before the hegemony of solid state amplification. Ralph and Julius have a lot in common.
This is the underside of one of the H3a's that I have. The Panasonic caps on the upper right (under the electrical tape) are not original to this build and were added later.
Edits: 04/02/15
That looks like a zener diode nightmare!!!
Julius used the zeners in a daisy chain to do the alignment procedure on the early versions of that amp, the pair that Ted and I did we brought them up to date using a single zener and an adjustable resistor, much easier, that amp has chains of 10 zeners in a row...WOW That's Beautiful!!!
I'm sure George will suggest a complete rebuild, that will be pricey but money well spent. They are awesome sounding amps.
I'll check the stereo amp for model number when I return home, I'm using it in my bedroom driving a set of Von Schweikert model 4's it has no problem at all driving them.
The stereo amp will put out 60 watts per channel, the mono like yours will put out 90 to 95 watts with a strong set of matched tubes properly aligned.
I doubt you would get that much power into 8 ohms. The downfall of the Futterman comes when the impedance reaches 2 to 4 ohms, which is sadly not uncommon in "modern" multi-way highly inefficient speakers built to be driven by transistors. I never perceived a problem with a true 8-ohm speaker, however.
.
Edits: 04/05/15 04/05/15 04/05/15
in any case, I was just making conversation. I had no idea that my posts were offensive to you or to anyone else. Henceforth, I will be sure not to follow up any of your posts. I never even dreamt that I had a beef with you or you with me.
.
Edits: 06/08/15
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Edits: 04/05/15 04/05/15
I just found a record of a similar pair, fully serviced and incorrectly identified as H3aa's, that sold on eBay in 2013 for $1782.32.
Edits: 04/02/15
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