12AT7 cathode resistor
The schematic I have, which is from an owner of a TVA-1,
shows the resistor value at 2k2R. At the bottom is a note
stating that the "Latest TVA-1 has 47R in cathode". I don't
know which cathode the note refers to!? Possibly the output
tubes, in place of the 100R's.
The owner of the TVA-1 used it to power the base panels
of a Magnapan Tympani D-1 crossed over, with a Waldron
tube 3rd order xvr at 1000 cycles for the lowpass and a
simple 6dB cap filter to a Marantz 8B for the highpass.
The bass of the TVA-1 was awsome with GoldLion KT-88s.
The schematic I have, which is from an owner of a TVA-1,
shows the resistor value at 2k2R. At the bottom is a note
stating that the "Latest TVA-1 has 47R in cathode". I don't
know which cathode the note refers to!? Possibly the output
tubes, in place of the 100R's.
The owner of the TVA-1 used it to power the base panels
of a Magnapan Tympani D-1 crossed over, with a Waldron
tube 3rd order xvr at 1000 cycles for the lowpass and a
simple 6dB cap filter to a Marantz 8B for the highpass.
The bass of the TVA-1 was awsome with GoldLion KT-88s.
The schematic I used is available on line. Thanks for the response though, 33K is defintely wrong value, 3k3 cathode resistor results in 3.2 mA of tail current , 2k2 is around 4 mA.
The step network (4.7Meg in shunt with 0.022, in series with 470k) is pretty much useless, since the plate voltage of 12AX7 is only 25V.
Art
The step network (4.7Meg in shunt with 0.022, in series with 470k) is pretty much useless, since the plate voltage of 12AX7 is only 25V.
Art
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