Reality of tube amps
Almost all tube amps are built around their output transformers, one per channel usually the size of five or more cigarette packets, covered with a metal shroud. The entire performance of the amplifier is critically dependent upon the transformer's capabilities. Every note, every transient has to work its way through that lump of steel and copper, and as with all transformers, the signal passing through will be slightly (or greatly depending upon the design) corrupted by the magneto-electrical forces inside the transformer. So chasing some dream tubes to replace the ones already fitted to a tube amp is skirting around the issue: the real performance limitation is the output transformer which cannot be exchanged.
Originally Posted by BAS-H
I congratulate anyone smart enough to understand and wrestle with the many technical factors in the design of tube amps. But at best, they can only reach a very sophisticated point of compromise - getting rid of the transformer is the answer.
Alan A. Shaw
Harbeth Audio UK