Swapping the 33K resistor on the Fuzz Face Q1 collector...

[mordechai]

I just went back and forth between the standard 33K resistor and a 47K resistor on the collector of Q1, and I found I liked the 47K a lot better...it allowed for a more open, richer and textured sound, whereas the 33K seemed to tame or even mildly choke the bloom of the fuzz.  Can someone tell me what is actually happening there?  I read RG's article on the Fuzz Face but wasn't really able to take away from it what I needed to understand the way that this swap actually affects the signal.

[jpiddy118]

I believe you're changing the bias voltage going to Q1. Most people tweak the resistor on Q2 collector, which has a more profound affect on the tone, but there's nothing wrong with playing around with both, as well as the 470ohm resistor which bridges the two (that one can range from 220 to 1k depending on which schematic you look at).

[petemoore]

Can someone tell me what is actually happening there?
  It could be the way it is driving Q2, and is particular to your set of circumstances.
   Q1's limited swingroom between the bias of it's C/B would be further limited becuase a larger collector resistor would have a bigger voltage drop across it.
  This can be measured: 15k parallel 47k is...measurable...something like 10k, piggybacking the resistor after measuring the Q1C bias, then with ~10k will tell what the difference in Q1c bias is.
  It might be interesting to measure Q2bias as well, Q2B is common with Q1C, so Q2 bias should show a change in DC bias.   

[LucifersTrip]

I just went back and forth between the standard 33K resistor and a 47K resistor on the collector of Q1, and I found I liked the 47K a lot better...it allowed for a more open, richer and textured sound, whereas the 33K seemed to tame or even mildly choke the bloom of the fuzz.  Can someone tell me what is actually happening there?  I read RG's article on the Fuzz Face but wasn't really able to take away from it what I needed to understand the way that this swap actually affects the signal.

what are the collector voltages on Q2 for 33K and 47K?   You may have chosen transistors where the 47K gets you closer to the 4.5v sweet spot.

[mordechai]

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what are the collector voltages on Q2 for 33K and 47K?   You may have chosen transistors where the 47K gets you closer to the 4.5v sweet spot.
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I'm using 2n404s...they sounded quite good with the 33k but seem to have come alive and roared a bit more with the 47k.

[skiraly017]

So this kind of got me thinking...is there a preferred mojofied bias range for Q1?