I'm finishing this amp here and works pretty well the power amp and the 2 channels (normal and bright) but the other channel, vibrato/tremolo is getting a overdrive on instead a vib/trem effect..
I'm trying to test it with a 12ax7 instead a 12au7 (I dont have a 12au7 here, i bought 2 of them, but left 2 weeks to be delivered)... BUT just for test, I changed the cathode resistor from V3 to 47K instead a 1.5K, and the effect dont worked.. Nothing at all of vibrato or tremelo, nothing..
I wanna be sure that's because I changed the tube... Anyone can help? Perhaps explain to me how this effect channel works..
There's the schematic on attachment.
Thank you for read ^^
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I'm trying to test it with a 12ax7 instead a 12au7 (I dont have a 12au7 here, i bought 2 of them, but left 2 weeks to be delivered)... BUT just for test, I changed the cathode resistor from V3 to 47K instead a 1.5K, and the effect dont worked.. Nothing at all of vibrato or tremelo, nothing..

I wanna be sure that's because I changed the tube... Anyone can help? Perhaps explain to me how this effect channel works..
There's the schematic on attachment.
Thank you for read ^^

Do you have LFO output signal from V1a, and at anode/cathode of V1b ?
Why did you choose 47k ?
Do you get acceptable amplified input signal at anode of V1a and V1b ?
Why did you choose 47k ?
Do you get acceptable amplified input signal at anode of V1a and V1b ?

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