Our best tone knob is the volume knob

[Mark Kleinhaut]

On the guitar, rolling off the volume knob darkens the overall tone, but very differently sounding than the tone knob. Anyone care to explain the electronics of what’s going on here? I love the volume knob effect, the tone knob, not really so much.

[princeplanet]

Depends on the guitar (or pups) though. I'm sure I've played guitars where the volume attenuation did not affect the relative treble.

[Mark Kleinhaut]

Depends on the guitar (or pups) though. I'm sure I've played guitars where the volume attenuation did not affect the relative treble.

Humbuckers. I’ve never played one where volume didn’t change the tone.

[58flame]

You can switch to 50’s style wiring to retain treble when you roll off the volume.

[hotpepper01]

I play bigbands only. I hate it when I have to switch from playing rythmn to solo and turning up the volume knob changes the tone to trebly. It requires to roll off the treble as well. That is why treble bleed circuits are IMHO such a blessing.

[Sam Sherry]

The explanation on Fender.com is pretty good:

When you turn the volume pot (potentiometer) down, you gradually lose the treble part of the signal, as the guitar will sound less and less bright and muddier the further you go. This is due to the relation between the pickup and the potentiometer’s resistance—how a device reduces the electric current flow through it—and capacitance—the ability to store electrical energy—(in addition to guitar cable’s capacitance).

Basically, resistance and capacitance are inversely related. So when the volume is up, the only frequencies being blocked from getting through to pedals and amps are too high to have much of an effect on the ear. Turning the volume down raises the resistance, so the frequencies that are cut off dip are the high ends that you can hear—hence the denser tone.

The bottom line is that it's always a compromise.
Run the volume wide-open and change the amp-volume: Tone changes
Put in a treble-bleed: It shifts the change-points but the tone is still affected
Run the volume wide-open and use a clean boost pedal: They say the tone isn't affected, but what would an experienced producer like Mark Kleinhaut say?

[Oscar67]

Our best tone knob is the volume knob

I agree, although it differs from guitar to guitar and it ranges from profound to very subtle. I use the volume knob as a tone knob more than I do the tone knob itself. There are also guitars which sound best to me with the volume all the way up, with those I use a volume pedal to maintain the tone.

[skiboyny]

It got to do with how the tone cap is placed. On modern wiring the tone cap is placed on the center lug of the tone pot. As you turn the volume down some of the high frequencies are sent to ground. Using the tone control will have a more dramatic effect at sending the highs to ground. Conversely the tone pot will not affect the pickup volume. If it's wired 50s style the tone cap is placed on the bottom lug of the tone pot with the middle grounded. This will not affect the tone when you turn the volume down but the tone control affects the pickup volume. So in the end it's the resistance of the controls and how it's wired.

[sgosnell]

I don't think there is an answer that fits all. There are multiple ways of wiring guitars, and while they all work, they have somewhat different effects. The way I personally prefer is to just have a volume control, no tone control. That said, most of my guitars have tone controls because they were set into the top at the factory, so I live with them, and just never turn them down at all. The amp does an acceptable job of setting the tone I want, and once set, I don't often want to change it. I do tend to rewire my guitars to the Benedetto-style circuit, as shown. It has minimal change in tone as the volume is changed, but still some subtle change. So I usually crank the amp above the volume I intend to play, and roll the volume back. Since the tone and volume controls are wired together, there is no way to avoid coupling entirely. Turning one knob will always influence the other to some degree, but I prefer to minimize it as much as possible. That's just what I prefer, and not necessarily what anyone else will prefer.
Bravo wiring diagram.pdf

[omphalopsychos]

I like to set both my vol and tone on guitars such that I have enough 'headroom' to go too far both in amplitude and in high frequency range. I do this because I frequently find myself needed to be louder or brighter than originally planned. So I usually set my guitars to 70% on both vol and tone pot and tune in my amp to give me what I think is a nice tone there. That way when I comp, I back off the volume a touch and it also darkens it enough that I don't need to mess with the tone pot. Then when I need to solo, I have plenty of room on each pot to adjust volume and brightness if I need more of either.

[deacon Mark]

All I want is a single volume control and do the rest with the amp. How about a Wesmo L5 with only a volume control? Send me one please.

[Litterick]

Pete Shelley of Buzzcocks did not like tone controls. He felt they muffled the sound. So he had Gordon Smith make him a guitar with only a volume control — which he used as an on-off switch.

[aquin43]

With typical jazz guitar pickups and pots and tone up full:

The tone and volume pots load the pickup and, because of its inductance, they would cause a high frequency roll off. With the volume up full, the cable capacitance is connected across the pickup and, combined with the pickup capacitance, it resonates the pickup at around 2 - 3 kHz. This restores the pickup level in the treble region and gives the normal bright sound.

As the volume is turned down, two things happen. The pickup no longer sees the cable capacitance directly so the resonance moves up towards its natural resonant frequency. This is usually too high to be perceived as a treble boost on a guitar amp which will have a speaker with a limited frequency range. Also, the resistance seen looking into the jack is increased and that produces an extra treble roll off with the cable capacitance.

[andrew]

A pedal with a buffer in it can help retain some of the high end when the guitar's volume is turned down. The effect is more dramatic with some pickups than others.

[GuyBoden]

No knobs, use an expression pedal and EQ?

[alltunes]

Pete Shelley of Buzzcocks did not like tone controls. He felt they muffled the sound. So he had Gordon Smith make him a guitar with only a volume control — which he used as an on-off switch.

I have an Eastman SB55V (Les Paul Junior) that has a “treble lift” meaning when you turn the treble knob all the way up it clicks and bypasses the circuitry effectively making it a volume knob only guitar.

Re: on-off switch….last bunch of years I use a clip-on tuner and just lower my volume for silent tuning. Aside from not having a tuner on your headstock I can’t see why one would want a tuner pedal on their board.

[Sleeko]

My Campellone Special was the only guitar I owned that didn't have a tone control and I dearly missed not having one.

[6v6ster]

I’m glad I’m not the only weirdo who hates the tone control and uses the volume.
man, despite what everyone claims, I still find the 50s wiring rolls off some highs. Not as bad but still plenty.
Treble bleeds can be perfection but the values of the cap/resistor needs to be adjusted for each pickup individually. As well as what kind of treble bleed.

[bluejaybill]

My Campellone Special was the only guitar I owned that didn't have a tone control and I dearly missed not having one.

Yes, mine does have one and I'm glad it does.

For me, I also use the 75% on both tone and volume so I have somewhere to go if needed. I only sometimes need brighter when playing with others. And I also have an EQ pedal on hand.

[Oscar67]

With typical jazz guitar pickups and pots and tone up full:

The tone and volume pots load the pickup and, because of its inductance, they would cause a high frequency roll off. With the volume up full, the cable capacitance is connected across the pickup and, combined with the pickup capacitance, it resonates the pickup at around 2 - 3 kHz. This restores the pickup level in the treble region and gives the normal bright sound.

As the volume is turned down, two things happen. The pickup no longer sees the cable capacitance directly so the resonance moves up towards its natural resonant frequency. This is usually too high to be perceived as a treble boost on a guitar amp which will have a speaker with a limited frequency range. Also, the resistance seen looking into the jack is increased and that produces an extra treble roll off with the cable capacitance.

This seems to be what PRS addresses with their TCI approach. What comes further down the line changes the pickup’s resonant peak as it comes out of the amp, i.e. it changes the pickup’s tone as you hear it. The whole TCI thing seems to be shrouded in some mystery, my take on it is that they look at every part in a guitar which has electrons going through it and tune the complete assembly in such a way that the pickup’s resonant peak (and therefore its core sound) is maintained, i.e. that TCI compensates the effects of the wiring harness on the pickup’s core sound.

[Doctor Jeff]

I play bigbands only. I hate it when I have to switch from playing rythmn to solo and turning up the volume knob changes the tone to trebly. It requires to roll off the treble as well. That is why treble bleed circuits are IMHO such a blessing.

You need this my man. One of my favorite recent purchases.

[Doctor Jeff]

As discussed in another thread, my Gretsch 6117 reissue has no tone knobs. It has a treble bleed cap for the master volume, but none for the individual pickup volumes, so when sound is turned down on those, the treble goes down.

Turning the pickup volume down and the master volume up is the secret to getting that sweet, dark, creamy jazz tone.

[orri]

Anyone care to explain the electronics of what’s going on here?

This is rough schemetic of a guitar tone circuit:
We assume 500k pots, 22µF tone cap and 1M amp input. I put the volume pot as two resistances which add up to 500k.



I remember doing the math once, but it got quite messy. What you do is that you calculate a transfer function which shows you the frequency response where both Rvol and Rtone are variables, you'll see that both will affect the frequency response.

Instead of doing the math again we can do a bit simpler exercise. We see that the signal current has two vertical downwards paths to "choose" from depending on which has the lowest resistance/impedance. One is through the tone cap (and tone pot resistance), which will cut high frequencies, and the other is through the volume pot and the amp input resistance.

If the volume pot is at max, we have the 1M amp resistance in parallel with the 500k of the volume pot. That combined is 333k. As we lower the volume pot setting the that path resistance will gradually get closer to 500k.
So this max setting makes it a bit "easier" for the signal to not get filtered through the tone cap. If we use an amp's low input, This difference gets bigger.

So to summarize.
1: Lowering the tone knob setting, will lower the resistance of the path through the tone cap
2: Lowering the volume pot setting, will raise the resistance of the path through the volume pot and amp input. (making the tone cap path more "appealing").

[Jimmy Smith]

Wow, noone knows the answer?

Turning down the volume knob uses resistance to darken the sound. This dampens the entire signal making it sound smoky since there are still highs and mids.

Turning down the tone knob uses capacitance to darken the sound. This cuts highs and usually mids above a certain point as determined by the cap. This simply lops off a chunk of the highs/mids while leaving the lows.

You can lower your cap value if you want the tone knob to feel more like the volume knob.

[orri]

Turning down the volume knob uses resistance to darken the sound. This dampens the entire signal making it sound smoky since there are still highs and mids.

Turning down the tone knob uses capacitance to darken the sound. This cuts highs and usually mids above a certain point as determined by the cap. This simply lops off a chunk of the highs/mids while leaving the lows.

This makes limited (yet some) sense from a theory perspective.
Both pots are resistors. Resistances alone do nothing to the frequency response.
But because there is a tone cap in the circuit (as well as a reactive component of the internal impedance of the pickup, and perhaps other significant reactive elements like cable capacitance), the resistances of the tone and volume pot will affect how much of the signal with get filtered by the reactive circuit elements. Because the tone and volume controls are at different points in the circuit it will affect the frequency response differently.

(The volume pot's initial intention is obviously to decrease the volume but the changed frequency response is a side effect).


But you can also use words like "sound smoky" to describe your perception of the difference. That's perhaps more useful from a player's perspective.