Electric guitar tone won't dump highs

[curtispaulchun]

Replaced fezpar tone control (a500k & 0.01uF) & checkwd all solder joints & conductors & groundings, they all perfect, yet can't dump highs. So next replace a500k volume (alpha full sized) and see? Volume functions perfect, volume wiper feeds amplifier also feeds thru series connected .01uF into high leg of a500k tone, tone's low leg unused, tone's wiper soldered to ground using tone canopy as ground, all components have groundings (pss frame, pot canopies, lowleg vol pot, wiper tone pot, wraparound guitar intonation bridge via pressfit ferrule bushing seated into deep into the well contacting the penetration exposed tinned copper conductor.

Look the hand drawn logic diagram

[The Dude]

...tone's wiper soldered to ground using tone canopy as ground...

Have you verified that the tone canopy is actually grounded to the circuit or jack sleeve? Check with meter if no obvious connection.
Also, a picture of the actual wiring might help. Your diagram looks right.

[mozz]

Maybe you can't hear the .01 and need a .047. Other than that, hook the cap up direct to vol wiper and gnd, see if you hear it there.

[pdf64]

Yes 0.01uF is kinda low value, especially with that 50s wiring. The latter greatly reduces the effect of the tone control when the volume isn't set up at full CW.
I also suggest a higher value cap, but try wiring boyh the volume and tone controls to the 'load' node.

[J M Fahey]

You posted exact same question on 4 (four) Guitar Forums, why?

What is a "fezpar" tone control?

The tone control is wired wrong.

[mozz]

How is it wired wrong, you can take the tone from the vol input or wiper.

[J M Fahey]

The tone pot is wired wrong .

* Capacitor to pot *wiper*
* You can short wiper to pot top lug (as drawn).
* Ground bottom pot lug.

That way tone action is smooth, clockwise is brighter, counterclockwise is darker, that is the proper operation.

As shown it works backward and all the effect happens in the last 10% of rotation.

And it might do nothing at all if said port is one of those with a cut track to remove it from the circuit when on 10

Rewire it and post results.

[pdf64]

The tone pot is wired wrong .

* Capacitor to pot *wiper*
* You can short wiper to pot top lug (as drawn).
* Ground bottom pot lug.

That way tone action is smooth, clockwise is brighter, counterclockwise is darker, that is the proper operation.

As shown it works backward and all the effect happens in the last 10% of rotation.

And it might do nothing at all if said port is one of those with a cut track to remove it from the circuit when on 10

Rewire it and post results.

Those are very good points J M

[mozz]

There's no direction on pots shown. Could be a left handed guitar. Simple as swapping wires if there is a problem. It will work.

[J M Fahey]

There's no direction on pots shown. Could be a left handed guitar. Simple as swapping wires if there is a problem. It will work. ......

Unless an arrow is drawn saying otherwise (as in VOX Bass-Mid control), if drawn vertically (as here) top lug is assumed to be clockwise/Hot/bright/"10"/maximum volume and bottom lug is assumed to be ground/"0"/dark/zero volume.

No arrows or indications here yet we all know which way those wipers move.
Top is maximum of whatever it controls and bottom is minimum , including zero.


As drawn by the OP, top which is 10 on the knob is *dark*, and to boot , reaching there is awkward because it uses the highest resistance section of a Log track. So it is wrong (or "worst" if you prefer to call it so).

What I suggest has tone pot dark setting counterclockwise/"0" and reaches it using the progressively lower resistance art of a Log/Audio track.
What all correctly wired Guitars do, by th way.

Your two examples match my suggestion: capacitor in series with a properly wired log taper variable resistor to ground, which is NOT what the OP shows.

Cherry on the cake: many guitars now use a tone pot where track is broken/cut (on purpose) so on 10 (b rightest setting) the whole ton e network is removed from the circuit an d stops loading the pickup, which now becomes louder-brighter.

If wired as shown by the OP , pot does nothing 95% of the travel because it is disconnected, and does everything on the last 5% because wiper jumps to the other side of the cut.
A mess.

[mozz]

The drawing does match what the original poster shows.

[Helmholtz]

Post #1 is not very clear.
Even with reverse wiring of the tone control and cap being only 10nF there should be a noticeable treble cut effect with the tone at zero.

Wondering if the OP will give feedback.

[J M Fahey]

The drawing does match what the original poster shows.

Drawings on post #9 are the *opposite* of that shown on post #1

An *electrical" Schematic follows conventions I mentioned above, same as Fender tone stack schematic.
All those are electronic *symbols*, not physical objects.

On post #9 those are *drawings* of physical objects, a very different thing.

[J M Fahey]

Post #1 is not very clear.
Even with reverse wiring of the tone control and cap being only 10nF there should be a noticeable treble cut effect with the tone at zero.

Wondering if the OP will give feedback.

True.
Problem is that on the drawing on post #1 "0" is the bottom lug while the cap is connected to the top lug, a.k.a. "10", so setting pot to "0" will have minimal effect (inaudible)

As shown, treble cut, whether through .01uF or .047uF, will happen with knob setting on 10 , which is counterintuitive to put it mildly.

Unwritten but standard rule is to have darker sound with tone knob on 0, brighter when set to 10

How do your guitars react?

[Helmholtz]

Problem is that on the drawing on post #1 "0" is the bottom lug while the cap is connected to the top lug, a.k.a. "10", so setting pot to "0" will have minimal effect (inaudible)

Ok, but then there would be a significant treble "dump" with the tone pot on 10.
As a player I would rotate the pot and see what it does.

Let's wait for the OP to clarify..