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My first Tube Amplifier

I have a 40 years of audio history starting with Garrard Turntable, Fisher Intergrated(SS), ADS bookself speaker on 1978.

But I started using tube amplifier on 1999.

Since then I had been using only tube amplifier in my main system.

My last SS main amplifier was Krell KSA 150 to drive Apogee Duetta Signature speakers.


http://www.jadis-electronics.com/photos/ja500/45/3/ja500.jpg

My first tube amplifier was Jadis 500 which comprised of 4 pieces weighing 120 lb each.

B&W 801 driven by Jadis 500 gave most deep and powerful bass at my home.

But it generated too much heat so it was hard to use during summer.

It was memorable experience to use it for 4 years.

I may not go back to such monster tube amplifier again.



How about you?

What is your first tube amplifier?



I bet two cents on no one had used larger one as the first tube amplifier than mine.


shkong78

Showing 8 responses by roberjerman

roberjerman
4,319 posts
 
September 1981: Bought a rare single-chassis dual-mono Futterman H3aa (#111AB) OTL amp from Bob Heenan at Q Audio, Cambridge MA. $750. Used it with a pair of Quad 57's (22585, 25391). Sold it July 1991 for $600. It needed new tubes and servicing. Should have kept it! Anybody out there know what happened to it?
roberjerman
4,319 posts
 
Tube amp no.2 was a Heathkit AA100 bought from the original owner/builder (1963). I paid $25 in May 1993. Came with a still good quartet of 7591's and a GZ34 rectifier. Used it with my Quad 57's. Still have it!
roberjerman
4,319 posts
 
@atomheart411: see my two posts above! I'd go for a pair of W5's or a nicely restored Dyna ST70 with 6L6/KT66 output tubes!
roberjerman
4,319 posts
 
The venerable 6L6 (late '30s) is an excellent output tube. Limited to about 20-25 watts for a PP pair. Its sound quality is limited to the make of the output transformer. Cheap ones, like in the Mesa Boogie, have problems with bass and high frequencies (hysterisis distortion caused by core saturion at low frequencies and capacitance/phase shift affecting highs). Excellent output transformers can cost a lot (hard to build). Tango (Japan) may be the best! I have seen the Mercury (US) transformers advertised. You might consider buying a pair and using them in your Mesa Boogie as an upgrade! 
roberjerman
4,319 posts
 
Alternately, you could buy a nicely restored pair of Heath W5 mono tube amps. 6L6 PP with outstanding transformers (Peerless). A true classic! I have a pair, so it's an easy recommendation! Can be found on EBAY!
roberjerman
4,319 posts
 
@bdp24 : I've had Futterman OTL's  in long-term use with Quad 57's. They do sound great together, even though the impedance falls to <2 ohms at 20khz. Partly due to the Futterman's low output impedance (high feedback).
roberjerman
4,319 posts
 
@bdp24 : Ralph Karsten's OTL amps are based upon the Wiggins Circlotron and are inherently well-balanced. But they do have an output impedance of several ohms! Not good because of interaction with a typical speaker's varying impedance! Best used (like Futterman's) with autoformers.
roberjerman
4,319 posts
 
@bdp24 : The inherent problem with Julius's circuit has been getting the two halves of the output stage to act in balance due to differing gain (one half acting as a cathode follower). And the circuit requires high feedback to have acceptable distortion (60db) - not a problem because of the low front-to-back propagation delay.
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