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Richard's Stuff

About 4 years ago, I was given a beautiful Bombay Co tea sampler chest (I love tea, great gift!).  Here is an idea for what to do with the chest once it is empty!

10WPC Class A 6AS7 push-pull:

:6AS7 Tea Chest.jpg (73237 bytes)

This amp was conceived to be low cost, small and light.  The parts cost is around $250, the tea chest is 12.5"x11.5"x3.75" and it can be picked up using one hand.  As usual, a regulated PSU is used. This approach permits a very quiet B+ without the weight and cost of choke filtering.  It makes 10WPC in Class A.  (Using 92dB/W/m speakers, it makes more sound then I can stand.)  The sound quality is surprising, quite SE like until the program density gets very high then it sounds like most PP amps, a bit confused.  (If one considers that music is electrically a complex presentation of sinusoidal fundamental frequencies and harmonics of differing amplitudes and phases, it stands to reason that there is a limit to how well a push-pull output transformer can accurately maintain the para-phase summation process.  Thus as the density of the fundamentals and harmonics increase, the process breaks down more and more.)  I am pleasantly impressed with the 6AS7 as an output tube.  Of course, Ralph Karsten realized this years ago.