V1 in a 2204 Build .....

griff10672

griff10672

Well-known member
starting to finish up my first build .... a 2204 clone ... I've noticed on certain layouts I've found online .... there is sometimes a 10p cap across pins 1 and 3 on V1 .... some layouts it's there on others it's not ... others I've seen a 100p cap across different pins in V1 ...
what does it do ?? Is it needed ?
I'm trying to build a bone stock amp ..... so moving forward I can hear what ever changes I make and learn from them .
Thanks !
 
I’d leave it out. They are there to stop very high end oscillations and should not be needed in a well built 2204. Just make sure you run shielded coax to both grids on V1 and you will be golden.
 
V2a said:
It does the same as a plate bypass cap (but a bit better).
Click to expand...
Not quite. Cap from plate to cathode is in parallel with the miller capacitance of the tube from grid to anode. Cap across the plate resistor forms a high pass filter to suppress inaudible frequencies from causing problems to stability down the circuit further or to tame brightness depending on the value.
 
glpg80 said:
Not quite. Cap from plate to cathode is in parallel with the miller capacitance of the tube from grid to anode. Cap across the plate resistor forms a high pass filter to suppress inaudible frequencies from causing problems to stability down the circuit further or to tame brightness depending on the value.
Click to expand...
I know you know the difference, but the OP doesn't, lol. Merlin B favours this HPF, and I can't really fault him on that...
 
You must log in or register to reply here.
Back
Top