How to Mod Rat distortion pot to be less sensitive in super low range

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awakespace
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Joined: 30 Jun 2021, 15:51

Post by awakespace »

I basically use my rat between 8 and 8:30 o'clock - or right above zero on the the pot sweep. It is super hard to dial in with the stock design since every micro movement makes a huge difference. This is the only part of the pot range I use, so I'm wondering if there is any modification I can do to get more sweep in this range so that I can use this pedal more easily and so I don't have to spend a few minutes micro dialing it in if the pot moves a smidge?

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dai h.
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Post by dai h. »

was it 100kA? Pots can be different in the number of sections on the resistive track (the minimum for audio/rev. audio) is two. (What are generally considered) "better" pots might have 3, 4, etc. sections. Also they can have different percentage of total resistance at half rotation, such as "15A"(15 percent of total resistance at half rotation), "10A", etc. (I'm not sure exactly how this is worked out, but I've seen in mic pres that 10C (might be marked as "RD" as in "10kRD", with R=reverse audio, and D=10% taper) can be used for a 40dB range, and 05C for 50dB, and 25(?)C for 30dB.) So perhaps somewhere in there you can find a pot that behaves (resolves) more to your liking (that "goes" where you want it to). Also two of the same "15A"(or whatever) pots may not resolve in the same manner (which I'm guessing is due to a differing number of sections on the track). Additionally, I've seen interesting pots that have what look like some zero ohm end resistance measure such as solder on the end terminals to ensure an end resistance close to zero ohms (also conductive silver bearing epoxy is sometimes used from what I understand) which could matter if resistance very close to zero is required at end of rotation.

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Manfred
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Post by Manfred »

This sensitivity potentiometer could help.
RatInputMod.jpg

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x-tn
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Post by x-tn »

awakespace wrote: 30 Jun 2021, 16:01 I basically use my rat between 8 and 8:30 o'clock - or right above zero on the the pot sweep... This is the only part of the pot range I use, so I'm wondering if there is any modification I can do to get more sweep in this range...
Replace the distortion pot with a A10k pot and try. If the maximum distortion is still a lot, replace the pot with a lower value one, for example A5k. Decrease or increase until you find a good value. If you don't like the sweep then try a B tapper pot instead of A.

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Eet3m
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Post by Eet3m »

I can confirm that a 10k pot does the trick, I left the old 100k pot in and just soldered the 10k one across the outside lugs. I love the Rat as a low gain pedal and this definitely achieves that. Don't mind the very awkward placement of the knob, I'll get around to drilling it in later haha
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