I'm trying to calculate voltage ripples on bulk capacitors of my guitar amp. Here's a schematic of it:
According to formula Vpp=I/fC, that is Vpp = 0.82/(2*50*0.0011)= 7.4V
I = 0.82, transformer is rated 30W, for rough estimation 30W/36.6V, it's going to be less at maximum load.
C = 0.0011, since two capacitors are in series
Aren't 7.4 V ripples way too high for this application. There are planty of information on the internet about ripples. I'm pretty sure I got it right, or am I not?
The main question is 'if calculations are right, are 3.7 V ripples OK considering schematic above?'
But I more inclined that something is missing in calculation, because I can hear 100 Hz hum, but it is hearable only when ear is <10cm from the speaker. Considering speaker is rated 15W, I bet it's OK.