Fatpants 2013 questions

[midwayfair]

1) Is R6 necessary?
2) Is grounding R7 also necessary?

My assumption is that R6&R7 this creates a voltage divider with 100K output impedance, but the gain of the buffer is already slightly below unity. Is this mainly to trim a small amount of high frequencies, or is it because otherwise we'd have DC offset?

3) If I'm building with the buffered bypass, is there any point in including R1, R2, and C1? Past C2 I don't see any changes to the tone shaping, so I'm not entirely certain if this was all part of the "works better with humbuckers" changes, or if it was just to cure pops in true bypass arrangements without the input cap.
4) Is C1 now necessary due to the positive bias from R4, or will the FET gate still be at ground potential?

I also note that the C1/C2 change does create a very small amount of attenuation at the low E.

[madbean]

Obviously, it will work without R6. I typically put some small current limiting resistor on the outputs of circuits by habit. It's impact is very small, so it's safe to omit it if you want.

Look again: R6 and R7 do not make a voltage divider. R7 pulls double duty: setting output impedance for the buffer, and as a signal limiter before the subsequent gain stage. It also grounds the input of the gain stage in buffer mode. This seemed to be the most economical way to arrange the circuit at the time.

You don't have to include R1 and R2 in the buffered mode, but you do need to include C1. Without it you will have DC on your guitar volume pot.

Low end attenuation is a good idea in a boost, IMO. There is no reason to boost down into subs. It just makes it muddy.

[midwayfair]

Obviously, it will work without R6. I typically put some small current limiting resistor on the outputs of circuits by habit. It's impact is very small, so it's safe to omit it if you want.

I tried it with an without ... I think it's better without it. The buffer is actually a little brighter. I was mostly trying to get away with converting an old version, but it turns out I need to replace the whole board anyway (there's something very, very bizarre happening with the first one I built).

You don't have to include R1 and R2 in the buffered mode, but you do need to include C1. Without it you will have DC on your guitar volume pot.

Did some experimentation: Excluding R4 gets rid of the DC on the guitar when skipping C1. Of course, this dickers with the headroom of the buffer, so leaving C1 is probably a good idea.

I really like the new version overall. Having the third body switch position was a good idea, as it turns it into more of just a preamp. I might hardwire in the soft switch since I don't have another switch hole in this enclosure.

[madbean]

I'm glad you like it! It is a simple circuit, but you can easily do a dozen variations of it that sound good. Probably why I release a new version every year