Treble bleed alternatives

[picknconk]

Hi folks,
I've got a hot rodded Kay with a HS Filtertron in the neck, and a Dynasonic in the Bridge, and with your help I've dialed in the tone caps to where I like them(.022 in neck, .033 in Bridge), but I dislike the treble rolloff when backing off the volume. I read an alternative wiring to the installation of a treble bleed pair on the pot. It involves running the wire from the vol. pot to the input lug of the tone cap, not the center lug. My tone caps(paper in oil) are mounted from the center lug to ground. Any and all suggestions will be gratefully appreciated. Thanks...Bob

[David Schwab]

You can try it, but the tone pot isn't the problem with the treble roll off, the volume control is. You can test this by removing the wire to the tone pot and you'll see you still lose some highs when you turn down the volume.

The alternate wiring makes the tone control have less effect as you turn down the volume control.

Other than running the signal through an active buffer, the treble bleed cap/resistor trick is the only thing I know of.

[picknconk]

Thank you, David. I knew the volume pot was where the bleed circuit would go. The alternate wiring I was told would make for "a more transparent" sound and more interactive. So, Could I have a suggestion for the component values? I've seen .001 with 110K, .001 with 220K, 500pf with 330K. What values make sense to you fellows? Do I use different values for the Filtertron and the DynaSonic?
The rolloff is far more noticeable on the Filtertron...Bob

[J S Moore]

I think what you are talking about is "50's wiring" where you connect the cap to the output lug of the volume pot rather than ground. There is a treble bleed circuit with a cap and resistor ( the values of which I can't remember off hand) that connects between the input lug and the output lug of the volume pot.

50's wiring make the tone and volume interactive as well so and adjustment of one alters the other slightly. Once you get used to that aspect it's great. You don't lose the highs as you roll off the volume.

[picknconk]

The one thing I can't do is place the cap in between the volume and tone pots. That's the on aspect of 50's wiring I can't due because of the nature of the body cavity. So what I was told about was the connecting wire from the volume pot to the input of the tone pot. I'm still open to the bleed circuit, but I'm hoping to get value suggestions based on people's experience with them....Bob

[Ward]

I use .0012uf and 130k resistor in series with 250k volume pots and .001uf and 160k in series with 500k volume pots. Both work very well.

[RedHouse]

I use .0012uf and 130k resistor in series with 250k volume pots and .001uf and 160k in series with 500k volume pots. Both work very well.

Yes, I totally agree with that.
(although I use different values)

Some will advise using a resistor/cap in parallel, but when you add that across pin2 and pin3 of the pot it alters the taper too much. Using the resistor/cap in series doesn't mess with the taper.

[picknconk]

What values do you use, please?...Bob

[RedHouse]

What values do you use, please?...Bob

It's not a recipie, your values will be different than mine.

Depending on the instrument, the pots, and the wind, one has to add treble bleed relevant to what things sound like after the pickups are installed ...then the part value choices get made.

You'll need to do your own experimentation with the pickups you use, and the instrument they are installed into.

[David Schwab]

Duncan shows the values of a .002µƒ cap and a 100K resistor. So there's another variation.

I agree with Brad that so sometimes need to tweak the values to match the guitar/pickups/pots etc.

[frankfalbo]

My treble bleed mod (we'll try to get it on the website at some point) is a little more intuitive in that I take the capacitor (whether you like it in parallel with a resistor or not) and connect it to the unused lug of the tone pot. It requires the tone pot to be wired with the hot in the center, and the capacitor between the outside lug and ground. This works for your situation, where you say that you can't use the capacitor as the bridge between the two pots, although you could easily extend the cap with a wire.

In this configuration, the treble bleed works as intended, but as you turn the tone control down, the treble bleed is progressively removed from the circuit. What I hate most about treble bleeds is that when I want to work the tone control AND the volume control, I'm left with a midrangey hybrid of treble cut and bass cut (which is really what the treble bleed mod is in the circuit) The treble bleed allows highs to pass while the rest of the signal is being lowered. That's tantamount to a low end roll off, unless you get the cap and resistor values exactly right.

Anyway I don't know if that helps you on your particular guitar, but when I heard the word "interactive" I thought of mine being interactive with the tone pot. If you happen to be playing with the volume at 75% for example, the tone pot still brings good value to the equation by simultaneously lessening the effect of the treble bleed as it attenuates the highs. There are some great sounds in those ranges.

As for cap values, I usually take the easy way out and just run a .0022 with no resistor. It's more dramatic in the early part of the taper without the resistor, but I figure I have the tone control there to save me if I want to find more balance.

[pdf64]

250k pots are much less prone to treble loss (as they are turned down) than 500k pots.
So you'd rather use 500k pots as it has more top end when on full?
If you fit a no-load tone pot and a 250k vol pot, then the pick up is seeing the same load impedance (vol & tone on full) as if 500k vol and tone pots had been used.

[Possum]

...

For buckers I use the 50's wiring, turning the volume pot down doesn't kill the treble as much as modern wiring does. For a Les Paul remove any plastic coated wiring in there and use the vintage braid type stuff, that will help as well. I pretty much completely redo the wiring harness in any guitar I use for testing, it makes a nite and day difference compared to factory harnesses. The treble bleed thing is kind of a bandaid thing I think, never had a need for that.

[Mike Sulzer]

For buckers I use the 50's wiring, turning the volume pot down doesn't kill the treble as much as modern wiring does. For a Les Paul remove any plastic coated wiring in there and use the vintage braid type stuff, that will help as well. I pretty much completely redo the wiring harness in any guitar I use for testing, it makes a nite and day difference compared to factory harnesses. The treble bleed thing is kind of a bandaid thing I think, never had a need for that.

When you turn down the volume control, you introduce a series resistance that acts with any capacitance to ground located from the vol pot to the input of the amp, or pedal, to filter out highs. Most of that capacitance is from the guitar cable, not from the wiring from the pot to the switch and to the output jack. A cable might be 500pf. How can you get nearly 500pf inside the guitar? It does add up to more than a few inches, of course, and so there is some effect. But using low capacitance cable inside the guitar cannot get rid of the capacitance of the cable. In any case, that capacitance helps set the sound of the guitar by determining the resonant frequency.

[RedHouse]

For buckers I use the 50's wiring, turning the volume pot down doesn't kill the treble as much as modern wiring does...

I totally agree.

It's one of those things where the rubber-meets-the-road, it's where the EE types can't get it (mind over eardrums) but the musicians can (eardrums over mind).

...The treble bleed thing is kind of a bandaid thing I think...

Agree to that too.

I've noticed it's needed (treble bleed) much more by players who use solid state devices/amps and mostly by players who tend set up their live sound with the (guitar) volume knob at 10, then later turn it down and say "hey, where'd my sound go?".

Players that go straight into a tube amp, or set up their sound with the guitar volume under 8 have no need for the treble bleed as a rule.