High pass filter hack idea

InsideOut

InsideOut

Power User
I was thinking about having a tech put a high pass filter on my volume pot of my guitar, so when I roll volume down, I don't lose so much high end. Then I got thinking (and I would be surprised if I was the first to think of this) that I could use the Axe Fx to simulate this.
Using Filter block set to high shelf, and expression pedal, with toe down level at 0db and filter gain at 0db, it is basically just passing signal through like normal. But then with heal down, the block level reduces to -35db (set to taste for your guitar) and the high shelf @ 3k bumps up to +9 db (again set to taste).
So with this, I can clean up my high gain tones and not sound dull. Feel free to try it and discuss.

Heal down

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Toe Down
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I'm sure it does work, but a treble bleed is an incredibly cheap and easy mod to do to your guitar. A resistor (or capacitor and resistor, there are lots of different types) is just soldered between lugs 1 and 2 on the volume pot. It makes most volume pots much more useable, is totally reversible and costs very little. If you ever decide you want to start modding any of your guitars, I think installing a treble bleed is a perfect project to start with
 
You're overthinking this. Just run guitar volume wide open and use the expression as a volume pedal. If the guitars vol and tone potentiometer are wide open, no high end is going to ground. The expression pedal controls the signal going to the front of the amp sim without any high end roll off.
 
RDeraz said:
You're overthinking this. Just run guitar volume wide open and use the expression as a volume pedal. If the guitars vol and tone potentiometer are wide open, no high end is going to ground. The expression pedal controls the signal going to the front of the amp sim without any high end roll off.
Click to expand...
I knew that was going to be a response because I thought of that too. However, the guitar I'm playing with is very dark in neck HB position. This goes further in giving it life when the volume is rolled down. Good point though. :cool:
 
I use treble-bleed in all of my guitars.

I run on the lead channel exclusively on my amps, treating them as single channel amps. A treble-bleed helps immensely when rolling down the volume to clean up the signal. The highs retain that snap.

On the modeler it’s so easy and convenient to use a “Clean” scene that I can adjust it so it’s not as necessary, but the lead scenes still benefit.

Early Les Pauls guitars used a different wiring than they do today, which retained more highs when the volume was turned down. If I were to get a Les Paul, that’s the first mod I’d do.
 
EQs can amplify something that's already there, but when there is nothing, they can't help.
Even when something is left, the weakened highs make a bad signal to noise ratio there.
It always better to not loosing the highs right from the start instead of trying to get them back.
I vote for the treble bleed.
 
Installing a treble bleed is extremely useful if you have high-output pickups. Rolling the volume control back a little cuts the volume and simultaneously has the effect of rolling off some bass content. So to me it's almost like getting more of a 'vintage' tone out of high-output humbuckers. Then just use the tone control if it gets too spikey.
 
So I took everyone's advice and learned how to install a treble bleed. I was able to successfully install it on my Harley Benton Fusion III. It does what it's supposed to do - retains highs when I roll the volume down. However, all the additional highs basically make it so the volume doesn't roll down, and amps don't clean up like they used to. Is this a common trade-off? It makes sense that you are not lowering the signal as much by bleeding the treble through.
 
InsideOut said:
So I took everyone's advice and learned how to install a treble bleed. I was able to successfully install it on my Harley Benton Fusion III. It does what it's supposed to do - retains highs when I roll the volume down. However, all the additional highs basically make it so the volume doesn't roll down, and amps don't clean up like they used to. Is this a common trade-off? It makes sense that you are not lowering the signal as much by bleeding the treble through.
Click to expand...
There are several ways to wire them in, and those and the various capacitor values affect the overall treble-bleed effect.

I've added them to all my guitars that didn't have them. A good thing to do before committing by soldering them into place is to use alligator clips to string together the combination of the capacitor and resistor if you're using a circuit that includes one. Then you can substitute different values and find the ones you like. Alternately, I remember reading about using a small trim pot, which made it easier to change the sound after the fact. A small trimmer capacitor would be useful too because then it'd be possible to fine-tune both the treble bleed and the effect on the volume control's roll-off.

https://octavedoctor.com/treble-bleed-circuit-what-is-it-and-do-i-need-it/ has a nice table of the values.

And, if I remember right, it gets real "interesting" with SSH and pickups that split.
 
InsideOut said:
So I took everyone's advice and learned how to install a treble bleed. I was able to successfully install it on my Harley Benton Fusion III. It does what it's supposed to do - retains highs when I roll the volume down. However, all the additional highs basically make it so the volume doesn't roll down, and amps don't clean up like they used to. Is this a common trade-off? It makes sense that you are not lowering the signal as much by bleeding the treble through.
Click to expand...

Wrong capacitor value? It should affect the highs only. A tone poti's capacitors value will not fit here. I'd recommend to start around 1pf.
 
This is what I installed in parallel. The volume taper just disappears - almost like off/on only instead of volume taper.

4 Submini Treble Bleed Kits Enough for 4 Volume Pots .002uf 150k Great for Kinman Mod​

 
Ok, so it is soldered right.

It seems the values are wrong for you.
You should try it without the 150k resistor because that has a big impact on the pots curve.
The idea of the resistor is to keep some lows and mids so it don't gets too shrill but you can also take a different cap value that only affect highs right from start, maybe 1pf?, and do it without a resistor.
 
666was999 said:
Ok, so it is soldered right.

It seems the values are wrong for you.
You should try it without the 150k resistor because that has a big impact on the pots curve.
The idea of the resistor is to keep some lows and mids so it don't gets too shrill but you can also take a different cap value that only affect highs right from start, maybe 1pf?, and do it without a resistor.
Click to expand...
I think before trying other values, I'm going to try series instead of parallel.

How much do you guys think the fact that the guitar has HB's and coil split has an impact on this operation?
 
I used 250pF with 500k pots and 500pF with 250k pots for ages, but switched recently to 180pF with 500k pots and 390pF with 250k pots after trying that in PRS guitars. It doesn't whack the pot taper too much, and the top end stays pretty nice through the whole range of the pot's rotation....
 
RDeraz said:
You're overthinking this. Just run guitar volume wide open and use the expression as a volume pedal. If the guitars vol and tone potentiometer are wide open, no high end is going to ground. The expression pedal controls the signal going to the front of the amp sim without any high end roll off.
Click to expand...
that's what I've always done
 
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