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Original Message

RE: Futterman versus whatever

Posted by decca4 on December 21, 2010 at 07:33:47:

Lew and Ralph
Please read my original post. I am reffering to the original Julius Futterman amplifier and not copies, interpretations or "improvements" of this amplifier. Also I am not addressing any particular person on this forum. However it is my impression that to often you find comments regarding the Futterman amplifier when it is really something else than the original that is meant.

Its mentioned in some posts that Futterman blows up or can hurt your speakers. But it has also been pointed out by some of you that this is not true of the amplifiers built by Julius Futterman.

I once visited Harvey Rosenberg in his home and he said: "We will gladly publish the circuitry. Anyone that tries to build one will find out that it is a self-destructing booby-trap. It took us more that a year to make it work without blowing up." Maybe Julius Futterman knew something that others did/do not.

If you want to pass judgement on how the Futterman sound or behaves compared to other designs I think that you should use one built by Julius Futterman properly refurbished and not an amplifier built by someone else.

I have had the opportunity to compare the OTL-3 and the Futterman H3AA. Although the circuitry is probably 90-95% the same they do not sound the same. The original was clearly better.

I suggest than when people wright about amplifiers using the Futterman topology that they would not call it a Futterman because it is not.