Fulldrive 2 - some confusion on inverting input cap/resistor values

[aion]

Can anyone help me confirm some Fulldrive 2 part values?

Almost all the schematics I've seen call for a 4.7k resistor with a 0.1uF cap coming off the inverting input of the op amp in the clipping section. However, the gut shots I've seen (and some discussion about Fulltone/TS differences) show what appears to be a 3.3k resistor in this section instead. (I can't tell the accompanying cap value from the pictures, but I've never heard of it being different than 0.1uF so will assume that value has stayed constant. Haven't had a chance to look at a real one.) This is R6 and C5, for reference.

This changes the corner frequency a great deal (339 Hz vs. 482.5 Hz) so it seems like it's a fairly significant tonal change and something that would be important to get figured out. I understand that Fulltone has probably changed these values over the long history of the Fulldrive 2, which is where the schematic differences likely originated, so I'm mainly looking for a recent major revision if possible.

[PRR]

> significant tonal change

1dB at most.

R-C filters are very gradual things.

If it's 3dB at 339hz, then it's 1dB at an octave up or 678Hz and probably around 2dB at the half-octave or 480Hz. If we change to a 482 corner, that puts 3dB where 2dB was. Can you hear a difference? It's really at the edge of perception.

Not to mention that a mass-produced box probably has +/-20% tolerance capacitors, so the "482.5Hz" can fall a quarter-octave either way, 386hz or 579hz, from one unit to the next.

I think the 3K3 is about added gain, 3dB, a for-sure difference. The cap drops-off a couple or three octaves of guitar bass (so the bass does not IM with the fuzz and sound too nasty), but is not a precision factor.

Yes,if you need to counterfeit the pedal to discriminating buyers, it matters; but for DIY then I think you do what you think best then tinker to taste.

[aion]

Very much appreciated! I didn't realize it was that inexact. I just saw the numbers and thought, "Wow, that sounds like a lot less bass." But I suppose we're not talking about a shelf here.

And nope, no counterfeits :) just a friend who thought the Fulldrive 2 was a good tonal target for a custom TS build, so I thought I'd start pretty close and then tweak from there as needed.

Thanks for the help!