Question about input cap

[Esppse]

Hey,

Usually I only build things 100% like provided layouts, I wanted to experiment a bit.

I built the simplest Bazz Fuzz and observed the effect of an input cap on the sound. Larger cap=more low before distortion.

I did the same to this here.

http://3.bp.blogspot.com/-vWMkonkn1jc/UQLbU8unvpI/AAAAAAAABFA/W1tUGTMe8CA/s1600/Marshall-Shredmaster.png

Does anyone know why changing the 10n cap to 68n, or 330n, or even 1uf had zero effect on the input signal? I tried it with both active and passive pickups, and put the caps on a switch, it sounded exactly the same on all settings.

Thanks

[PRR]

The 10nFd goes to a 1Meg resistor. This will pass down to 17Hz.

68nFd to 1uFd extends bass to 0.24Hz to 0.017Hz.

You don't have ANY sound down there. In fact the 10nFd looks generous.

Go the other way. 5nFd will have hardly any effect on guitar. 1nFd will shave the bottom octave or so.

[Fancy Lime]

However, with the 10n cap you have some phase shift up to 200Hz or so. In and by itself, that is irrelevant. But if you intend to split your signal before the Bazz Fuss and reunite the distorted signal with a clean one afterwards, you might run into phase cancellation at low frequencies, which sounds odd and hollow. Depends on the clean bypass circuit as well, though.

Andy

[Esppse]

Ah thanks for clearing that up. I knew it had something to do with the resistor. I'm just getting started figuring out how components affect the circuit. I built a diode selector on this and it sounds great. Oddly enough, they actually raise the volume, I must have put it in the wrong place, however the tone choices are great.

[PRR]

The phase shift will only be 90 degrees as the signal sinks out of sight. At 45 deg the signal is down enough it won't much matter unless your mix is real unbalanced. The effect is small.

For "linear" circuits, no objection to putting the cut-off SO low that we never know it is there.

In fuzzes it is sometimes more musical to shave the heavy bottom.

[Esppse]

OK so I did the switchable input cap mod. I found 1n had a very small effect on the sound. I used a 220, and now its super tight on the low end, very crispy sound. Thanks for the recommendation!