Tremolo Insertion point and NFB

[BrainDeadAmps]

Hey All,

I’ve built this single ended amp that is essentially a Princeton reverb circuit. Works great as is but I do have space for another tube socket and have been toying with the idea of adding a vibrochamp tremolo circuit to wiggle the recovery stage feeding the output tube.

I much prefer the overdrive character With no bypass cap attached the cathode of the 3rd stage. Would it be possible to insert the tremolo at the same point as the NFB at the cathode?

or is it necessary to have the bypass cap and added shunt resister so that they are attached at seperate points?

[HotBluePlates]

I guess you could attach both directly to the cathode.

With the series 100kΩ resistor, you're only getting something like 84mV of feedback at max output power.  I think that will be something like 0.75dB or less, and probably not really audible vs "no feedback."

[BrainDeadAmps]

Went ahead and did some experimenting this afternoon.

Unfortunatly with the bypass cap removed a tick came through the speaker, very loud and present. Put the cap back and it’s gone.

[WimWalther]

A tick came through the speaker, very loud and present. Put the cap back and it’s gone.

A rhythmic tick, like pop-pop-pop, as in a motorboating oscillation?