Volume/Tone Pot Query

[gilmoreguitars]

Hey Guys
Can I combine a 250k pot with a 500k tone pot?
My Gilmore ESG prototype is using 250k pots on both with a .473 cap on the tone pot.
The tone is very fat and bassy on both pickups.
Turns out it is a great rock sounding guitar when you plug it in to a Marshall with the gain on 10.
But when you clean it up, I would like a little more mid to treble control.
I was thinking maybe a 500k tone pot might do the trick.
Thoughts?
Thanks
David

[Eben]

Well, in a nutshell, yeah, you can.

In general, higher ohm value yields greater gain and treb tone response, with less compression.

If by "When you clean it up," you mean when dropping volume, then I'd ask first what caps you're using on the volume and tone pots?

If that's the issue, then in keeping with The Easiest Thing First Principle, I'd solder a .001uf cap between the hot lugs on your volume pot; that'll give you a decent treble boost as you roll off volume without changing pots.
Keep in mind that caps cut specific frequency ranges, so you can diddle around quite a bit with the concept if you're up for it.
If doing that ends up sounding to you like it robs the balls of your tone (AKA mid and bass), as a result, then yeah, I'd yank the pot and try something new, (It doesn't actually act on any low freqs, but it can sound that way, here's kind of a cool little piece on it, if you're interested.)

As I recall, you did this up standard three way switching, AKA a LP, yeah?

I'd go with the 500k as volume; that'd get you better trebs and mids, for my mind,
(Hence, using the 250k as the tone with a .047 cap)...

Then if you change your mind later, you can always ratchet the 500k down to 250k by putting a 500k resistor between the outer legs - End output should be 250k with no appreciable tweaking of the taper curve, and you don't have to remove and re-do everything...

Final thought, I've used a 1Mg audio taper pot on a volume circuit before, (Fender used them for a time as the go-to volume pot on Teles and Jazzmasters, I think, or maybe it was Jaguars...). Mine was for a Duncan P-90; it had real nice qualities. You could try one of those as well, it's always good to have one or two around anyway.



Urb

[gilmoreguitars]

Thanks Eben
Ya brow beatin sob
Inside joke...sorry!

I only have a .473 cap on the tone pot. No cap on the volume pot. In all of the wiring diagrams I have come across, I don't think I have seen a cap on the volume pot. It is my understanding...and I am pretty much at kindergarten level when it comes to wiring...that the cap on the tone pot is what allows you to roll off the higher frequencies whithout changing the volume of the singnal. So by putting a cap on the volume pot, wouldn't that in essence turn the volume pot into a tone pot?

On Saturday I plugged the guitar into a Marshall half stack. Turned the gain to 10 and the volume to not quite 2. The sound coming out of those four 12" celestian speakers was absolutely magical! It turns out, with the pickups chosen and the current 250K volume and tone pots with a .473 cap and a 3 way switch this guitar is a true rock n roll beast. You could frett the 5th string at the 5th fret and just use a bit vibrato on the string and conjure up that harmonic feedback that just goes on and on. The first time I tried that, I almost peed myself I handed the guitar to a very accomplished player and he proceeded to play Nobody's Fault But Mine a`la Led Zep. I actually had to go to the bathroom and pee
I think I am going to leave this one wired up as is.
I have a commission now for the Gilmore ESG #2. We will be using the same neck pickup but install the Dimarzio "Fred" or the "From Hell" in the bridge position. Work on that one won't start til October.
Also, on a personal note, our son is getting married on Saturday Sept 10. So will probably be here only sporadically over the next week or so.
Cheers.
David

[Eben]

Thanks Eben
Ya brow beatin sob
Inside joke...sorry!

Hee HEE!!

So by putting a cap on the volume pot, wouldn't that in essence turn the volume pot into a tone pot?

The answer is kinda, bu not really: A small value cap like I recommended across the volume pot will act as a treble gate, if you will, allowing some higher frequencies to pass as the volume is turned down. Again, though, like any cap, it only impacts a certain range of frequencies and won't do anything to others!

So, keep it like you like it, by all means, but put this info into your file system for future use!

And CONGRATS on the kid gettin' hitched Buddy! VERY COOL!!

Urb