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RE: Small IDHT tube cathode bypassing

Posted by drlowmu on July 6, 2015 at 09:28:53:
The commercial amp builder is dead wrong . LMAO. Amazing,..... but sadly typical in audio!!
Maybe eighty percent of what you hear in a two stage amp, is the driver tube. EVERYTHING about the driver tube is totally audible, and it demands to be built "as optimized" as you can get it. After all, if the driver stage loses ANY information, it is never received and "made up" in the finals stage, is it ? That logic does not take any EE degree, does it.
Rk bypassing on driver tubes should always be entirely done with only the highest-quality films.
Since no single cap plays the entire range of music perfectly, it is important to adjust the amp so it plays, at the speaker's voice coil, as you WANT it to, in as honest and as linear a fashion as possible. Only your ear is the judge here.
This requires multiple high-quality film bypasses ( get out your wallet ), to insure ALL the ranges are played, and all the music's nuances remain intact through the entire audio amplifier.
To date, ( since 1998 as far as I can tell, and in 2006, when I first attended RMAF to obtain direct experience ), I am very sure Dennis Fraker leads the audio world in Rk bypassing.
My present build, a Telefunken 1/2 12AX7, DCed to a Type 45, has a total of 24 film Rk capacitors doing duty on the Rk bypassing for the four triodes. I've been through three iterations of cap types the last few weeks, to get a more acceptable-to-me desired result.
AS a mater of fact, EVERY cap in a SE amp is IN the circuit, and EVERY cap needs to be fully bypassed IF you want the best possible result!! Cowboy logic, works !!
Other important build pointers,
(a) the film caps' orientations ( re: outer foil ) must each be properly determined and each installed properly "polarized",
(b) they must not touch each other's bodies, and
(c) not touch the chassis. Now you know.
Only YOU Raymond, can find the answers needed, ONLY by building and listening for yourself, until it suits you, and YOU are happy with the build.
Have fun, its a very cool trip.
Jeff Medwin