One more quick Axis Fuzz question

[rhdwave]

Hey all, one last Axis Fuzz question...
http://www.diystompboxes.com/pedals/axisfuzz.gif

In terms of the 2.2 cap just before the volume control.  What will changing this value do to the sound if anything? Is this simply a noise filtering cap or will it act as a tone filter in conjunction with the resistors coming before it?  The reason i ask is that I finally got the pedal i built for my friend working and it sounds great.  I like it's sound i think a little better than the one i had built for myself some time back.  Now the only difference i can find in the two circuits is that when i built the original, i didn't have any 2.2 caps on hand and so i combined a couple of different values in series which yielded about the equivalent of a 2.7 cap. 

Any responses are always greatly appreciated!
Much thanks!

[petemoore]

  Caps have increasing impedance as AC frequency gets lower and tries to pass through them..and are DC blockers [the lowest possible frequency, ie no frequency].
  Smaller caps in *series with signal path, at some value point..start rolling off low frequencies, smaller than that rolls off more low Freqs.
  Any type of capacitor can work there, non-polars have no polarity.

[tcobretti]

The 2.7 would allow slightly more lows to exit the pedal.  To add to what Pete said, usually the last cap in a pedal acts as a high pass filter, and the larger its value the more freqs it allows to pass.

[rhdwave]

Thanks guys for the replies! Now just to understand completely here: I thought that might be the the situation...that it is acting as a kind of filter at the end of the circuit.  So, just to be completely clear...I understand that as the cap gets larger, there will be more lows getting through (is that correct?) And if so...in this scenario, since the cap is hooked to the volume pot, will the lows that get through make it out as more lows in the sound of the pedal or will those lows be rolled off throught the pot's ground connection?  And also, as you said, Pete...concerning using caps in series: should there be a difference if say i had just used a 2.7 cap instead of two in series to equal that amount as far as the filtering aspect goes?

I know this is pretty elementary stuff, it just gets confusing to me.
I really appreciate the time that has been taken to answer some of these 'simple' questions for me!

Thanks again!!!

[tcobretti]

I should issue a disclaimer that I am not one of the smarter guys here, but I try to help out with the easier questions.

I understand that as the cap gets larger, there will be more lows getting through (is that correct?)

Yes, in all cases I know of.

Since the cap is hooked to the volume pot, will the lows that get through make it out as more lows in the sound of the pedal or will those lows be rolled off throught the pot's ground connection?

More lows in the sound of the pedal.  With some notable exceptions (I don't think this is one of them), the volume pot has very little effect on the tone of the circuit.

Concerning using caps in series: should there be a difference if say i had just used a 2.7 cap instead of two in series to equal that amount as far as the filtering aspect goes?

In most instances, it shouldn't make a difference.  But you do know that two caps in series will create a lower amount of capacitance (I believe it is roughly equivalent to the product of the caps' values divided by the sum), right?  So, two 4uf caps would be  4*4/4+4=2uf.  Running two caps in parallel makes their values additive, i.e. two 4uf caps in parallel = 8uf.  I may be wrong about this, but it seems like I read somewhere that this is the way stacking caps works.

[rhdwave]

Thanks again! I thought that was what was meant.  And yes...it was two caps valued at i believe 4.7 and 6.8 which in series came to roughly 2.7.  So that's that i guess.  I guess i'm just left with the prospect that certain components will be lucky or magical with their sound for whatever reason.  My friend got lucky in the components i chose for his pedal.  It's not to say that i don't like mine...i do...it's just that i like the new one better...it seems smoother or sweeter...less harsh and metallic sounding.  And the funny thing is, my pedal sounds like it has more treble in it, but his according to the capacitor discussion should have more treble. 

Maybe some things are just meant to be mysterious.  That having been said, i may still experiment with swapping some of the caps.  I just didn't really want to start messing with desoldering and all and not knowing really if it was going to make any difference to the sound.

If anyone has any other ideas, i'd be open to them...otherwise thanks for all the responses!

Peace