Single Ended Double Tap Ultralinear Transformer + Schade config. tests

[waltube]

But it is fun for us, and sometimes the journey is as important as the result

In general, I always search to get the best results using the best components available and, for power amp, the first one is OT
Then with test to maximize the circuit I decided to use.
Using some strange kind of mixture with sand and tube adding three or four type of feedback is not my goal.
One example of what I mean is here:

This is a freq. answer of an amp with 4 x 300B in p-p

With and without FB; 10 dB of FB that I normally use.
Red is without and blue is FB

The BW is 100 kHz at - 3dB, no FB, open loop!
Great OT and the use of Ecc88 and 6H30 helps.
There is a little peak. 0,5 dB, because there isn't cap on FB for compensation.


Walter