Again, could you please post the schematic? I can re-draw it for you.
hello ok i try to remember everything,its not easy job.
from direct coupled(by grid resistor and RK 4K7 for 6A3) like in the photos
the best choice its capacitor coupled,K40Y9, sound just better musically
each channel get triode 6S19P-E 300V regulator by two gas miniature VR tubes 150V in series
6A3 cathode caps are two PIO 160V 30uF//
30mA on lundahl LL1692A/25mA its just perfect in line out setting.
please do not come to said 300V too low, 10K input no good, direct coupled its better, grid choke moove to 6A3, electrolitic no need etc etc etc
the 6A3 grid resistor its 390K ohm not 390!!!
every step its tested in different configurations and humans like the sound,
FFT and THD its also very good so thanks no need to change anything,
this preamp its for a friend, my personal preamp its almost the same but 6B4G sylvanya double black plate or 6C4C and classic regulated power supply
and only one input for the moment. also cathode oil caps are bigger but 20uF
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thankyou Jazbo8 great job, really very nice
Kai this resistor lower H3 little, sometime i mount, not always,
also sound more airy, open , i feel, really i do not remember exactly
i do not find were i write down thd test, please do not kill my
wen i do diy there its a bit of measurement and also listening,
i now value should be 2K and no cathode bypass capacitor at lower triode
but sound colder
if you like math and calculations do not ask my!!!!
read this:http://www.valvewizard.co.uk/SRPP_Blencowe.pdf
Kai this resistor lower H3 little, sometime i mount, not always,
also sound more airy, open , i feel, really i do not remember exactly
i do not find were i write down thd test, please do not kill my
wen i do diy there its a bit of measurement and also listening,
i now value should be 2K and no cathode bypass capacitor at lower triode
but sound colder
if you like math and calculations do not ask my!!!!
read this:http://www.valvewizard.co.uk/SRPP_Blencowe.pdf
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