There is much information out there about the function of guitar pots as volume and tone controls but briefly:
For Strats, Teles, P bass, J Bass and other guitars with single coil pickups you want to use 250K pots and for P90’s and Humbuckers 500K pots. The reason for this is that single coils are inherently bright and the 250K value tames that whereas P90’s and Humbuckers are more mid focussed and so a 500K pot is better. Gibson went through a phase of using 300K pots and the result was very dark and dull sounding.
Interestingly Jazzmasters used 1 Meg pots for a whole host of reasons, but we like them with 250K pots as suggested by Lollar who say “1meg pots are "vintage correct" and give a brighter overall tone than 250k pots, but either will work. It's a matter of preference.”
"CG" Potentiometers by CTS
After many years we had CTS make pots especially for us. Based on the 450 series 15% B taper with brass shaft and thread and with a + - 5% tolerance and slightly higher nominal value so that the values do not drop so much from the stated value, but still marked 250K and 500K to keep the look vintage correct. The “CG” pots are audio log and suitable for volume and tone.
We also offer RS Guitarworks Superpots, these have been copied many times but never really equalled. The construction is different to standard pots in that the assembly is held together with a circlip at the top of the shaft, the track is screen printed and heavier so longer lasting and with a custom taper which means that a treble bleed is not needed as the value remains for longer before dropping off. They are also never lower than the nominal value of 250K and 500K, they are usually in the 265-270K and 515-530K range. They are not suitable as tone controls.
All the pots we have are USA spec which means a 9.5mm threaded shaft, 6mm 24 teeth split shaft or 6.3mm solid shaft.
Do’s and Don’ts
On split shaft pots don’t be tempted to spread or squeeze the tabs as the shaft is made from a hard and brittle brass and can easily snap.
When fitting Gibson style knobs lubricate the split shaft with soap or a drop of WD40 and try your knobs before you fit them or on an old pot first. Very small differences in the moulding of knobs or the splines can make the knobs tight this is not a defect just something that we have to deal with.
CTS pots are pretty robust but if you heat them a lot and for too long you can damage them.
Be careful not to let small shards of wire or spits of solder get inside for obvious reasons as that can short things out.
