Pots 101

impmann

I've just read somewhere that in the 1950s Gibson used Linear not Log pots in their guitars. Thats at odds with what I "knew" so wanted to sense check that with folks.

Linear pots would explain why the likes of Joe B prefer the way that older Gibsons react to tone and volume control inputs compared to modern stuff. But does that bear examination?

I've always had it drummed into me that 'proper' guitars had log and cheap stuff had linear... 

Cirrus

I don't know what was used in the '50s, but I know I found both useful I played around with both options of my Explorer's vol and tone pots - especially with volume, it just depends on how you play. If it's into a higher gain setup and you want to clean up, log makes more sense because to get to a clean sound from a high gain one, it's much less fiddly between 0 and 5 with a log pot. Linear gives you clean-to total distortion between like 0 and 2.

If you play a cleaner, less compressed setup, linear is more useful because you don't necessarily want the signal to fall away loads between 10 and 8.

ICBM

Linear pots are a different option rather than a sign of poor quality.

As far as I know Gibson always used 500K Log in the 50s, and only more recently changed to 300K Lin for the volume controls on many models. They did wire them differently in the 50s though, which makes them more interactive in a way a lot of old-school players prefer.

(Why they also changed to 300K, I don't know - it's that which is responsible for the duller/slightly muddy tone of these guitars rather than the linear taper.)

Linear for a volume control works pretty well, and doesn't give such a drastic drop-off as Log from 10 down to 8 or 9. It's usually better for a cleaner sound where you want a subtle gain control to back off the overdrive or an actual volume control on a true clean sound. Log works better when you want to clean up a heavily overdriven sound, exactly because it drops faster. Linear works better for 'violin swells' because the rise from zero is faster.

Linear does not work well for a tone control usually - it compresses all the variation into the bottom of the turn, so the control does very little from 10 down to about 3, then cuts off suddenly without as many useful in-between settings. Some people like this though, since it makes the tone control easy to use as a 'hand wah'. It's also sometimes used with a lower-value pot (100K or even 50K) for a jazz sound where the player would only want to use the range below about 3 on a normal tone control anyway.

So generally you want both Log, or Log tone and Linear volume - not the other way round as was commonly stated on various online sources…

Just to confuse things slightly there is not only one type of Log taper - the ratio can be different. Strictly speaking Log should only mean 10% of the full value at the halfway point of the turn, but Log is often used interchangeably with Audio Taper (A) pots which are avaliable in several tapers from 10% at half-turn to 30% at half-turn.

Even worse, some cheaper (typically mini) Log pots are actually two sections of linear track joined at the halfway point, since this is easier to make. These don't work very well for players who like to finely adjust the controls either. This is one of the biggest reasons to upgrade cheap pots, rather than the tone when they're up full.

FelineGuitars

Good points
I used to use CGE pots which had a custom Audio taper and I found them very even in rolloff , but sadly they stopped being made. Switching to CTS I had to get used to a different taper. 

I kind of like the CTS 550k ohm ones that Bare Knuckle supply but am still open to finding others that i like 

normula1

Has anyone tried the Emerson version of the CTS pots which apparently have a cystom taper?