Pots Caps lesson wanted

[illmusician]

I have not yet read into wiring of passive electronics and would like to know more about it. I have the East Retro preamp and it has a passive tone knob. I know pots are knobs but capacitors are they inside the pot?
I have read that foiled, sealed, jensen, or preCBS fender caps stand out, whats the hype about?
What does changing these thing do to overall sound?
Are there big differences in tone, or ideal resistance. and I guess resistance vs impedance for over all output?
I am guessing that one wants the least amount of resistance to get the full potential out of a passive pickup, then shaping that signal down with pots that trim small amounts of current to alter the tone without effecting the output?
Please guide me to a correct answer.

[bongomania]

The FAQ contains most of your answers, and Google contains the rest. I will clarify that a "pot" is the electromechanical rotating part that the knob is screwed onto; "caps" are smaller external components, and there are a great many different kinds that look very different from each other. As far as types of caps, we have had many threads about that, but my opinion is "don't believe the hype."

[Foamy]

The pots (potentiometers) for volume control the overall output for volume. The tone potentiometer feeds into a capacitor which allows a variable amount of signal to bleed off to ground thus changing the tone. A higher value capacitor will sound brighter than a lower-value capacitor.
There are many qualities to a pot. Some are linear and some are tapered. Generally for volume you want one that is (I think the term is) audio tapered. Because we hear change in volume differently, not linearly, a tapered potentiometer is advised.
Other than the value, you have how it feels to adjust it, and how well it holds its setting. Plus, many sizes and configurations.
Folks claim to hear the difference between various tone capacitors. I have not even tried. I use good quality caps I get from my local Fry's and have never tried the expensive ones. Maybe I am missing something.
But don't confuse resistance with capacitance.
I am sure you'll get a lot of replies.

[GlennW]

Originally Posted by Foamy

A higher value capacitor will sound brighter than a lower-value capacitor.

That's backwards. A .1uF is much darker than a .022uF. The cap with the larger value will bleed off more treble.

[dmusic148]

Originally Posted by illmusician

I have not yet read into wiring of passive electronics and would like to know more about it. I have the East Retro preamp and it has a passive tone knob. I know pots are knobs but capacitors are they inside the pot?
I have read that foiled, sealed, jensen, or preCBS fender caps stand out, whats the hype about?
What does changing these thing do to overall sound?
Are there big differences in tone, or ideal resistance. and I guess resistance vs impedance for over all output?
I am guessing that one wants the least amount of resistance to get the full potential out of a passive pickup, then shaping that signal down with pots that trim small amounts of current to alter the tone without effecting the output?
Please guide me to a correct answer.

The East pre has caps attached- see the little white boxes? That's them. On the U-retro deluxe they are right on the side of the tone pot.
Higher value caps bleed a wider range of frequencies than lower value ones. They all bleed the very highest frequencies, but higher value caps go lower, so you bleed off high-mids(very high) as well as treble.

The opposite is true of pots-higher value ones bleed less treble than low value ones. This is why folks with Jazz or P basses sometimes replace the standard 250k pots with 500k's- gives a brighter tone.

[Foamy]

Originally Posted by GlennW

That's backwards. A .1uF is much darker than a .022uF. The cap with the larger value will bleed off more treble.

Doh! Of course. I confused that with the value of the tone "pot" I think. Thanks for correcting that. :-)

[illmusician]

Originally Posted by dmusic148

The East pre has caps attached- see the little white boxes? That's them. On the U-retro deluxe they are right on the side of the tone pot.
Higher value caps bleed a wider range of frequencies than lower value ones. They all bleed the very highest frequencies, but higher value caps go lower, so you bleed off high-mids(very high) as well as treble.

The opposite is true of pots-higher value ones bleed less treble than low value ones. This is why folks with Jazz or P basses sometimes replace the standard 250k pots with 500k's- gives a brighter tone.

I get the pots replacement part. I have noticed differences in tone pots across different basses and have wondered why they changed the tone differently. Did the highway one basses have different caps in the "grease bucket" circuit or was that something different.