gres
Full Member level 4
It’s a lamp buffor on ECC88. Base diagram is taken from www.audioton.republika.pl , but i made some changes:
Diagrams you can find at previous web.
- extra potentiometer at output
- limiter of transmission range follower
After restart change was imperceptible so I add low pass filter <originally buffer should be addition for subwoofer>, but after I had added filter with Fg=640Hz, buffer made outstanding impression on me <althought is very smooth change, but limiting strand, sound goes to deep base with a note of middle tones that cause real vacuum tube sound. I goes one better and increased top frequency limit of filter to 3,5 kHz.
I have never listen music from real vacuum tube amplifier, but this what i made is much closer to vacuum sound then even best transistor. Plus I have great case.
I wanted to show of "massive" and "worm" elements <the same assumption was made by vacuum tube designers>
At https://www.elektroda.pl/rtvforum/topic1527096.html you will find more pictures and movie. Sound without lamp <transistor> and with buffer - to compare. There IS DIFFRENCE REALLY ! ... but it always could be better.