Tone Controls

Started by CodeMonk, June 14, 2008, 10:29:43 AM

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CodeMonk

I'm using this tone control in some of my effects:

(Thanks to beavisaudio http://img.photobucket.com/albums/v494/CodeMonk/tonecontrol.gif )
Works great, but I would like to get more treble out of it. I would like it if i didn't lose anything on the bass end of things, although a little bit would be ok I guess.
Any ideas?

Thanks

loss1234

can anyone explain how this works??

thanks

cloudscapes

from what I can tell and based on my limited knowledge, turning the pot towards 3 routes the signal through a .004uf cap, hence only gives out low-end out the pot's middle lug. turning the pot towards 1 routes "clean signal", but then the low-end is filtered to ground by a .01uf cap and only treble remains when it goes out of the pot's middle lug. I may be wrong though. in fact I'm probably wrong. I'm still just learning all the theory and math
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slacker

#3
That's pretty much it cloudscapes only the other way round :)

It's the tone control used in the Big Muff and other things like the BSIAB2, Sonic Distortion, Jade Fuzz and BOR.
C1 and R2 make a highpass filter
R1 and C2 make a lowpass filter
The pot then blends between the 2 filters, turn the wiper all the way towards lug 3 and you get a highpass all the way towards lug 1 and you get low pass. In between you get a mixture of the 2.

If you want to experiment with it download Duncan's Tone Stack Calculator and select the Big Muff model.

CodeMonk

Thanks slacker.
I'll give that a go when I get home, sometime tomorrow.

ayayay!

QuoteI would like to get more treble out of it. I would like it if i didn't lose anything on the bass end of things

OK, call me stupid becuase I've never tried this tone control before, but if it doesn't have enough treble, and doesn't have enough bass, what makes it a good control then?  Don't get me wrong, I love Dano @ BeavisAudio ;D 

Does anyone highly recommend this?  Like I said, never tried it...
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CodeMonk

Ok stupid :) (just kidding)

It has plenty of bass.
I just would like to get more treble out of it.
If that means I end up losing some bass, I can live with that, but I would prefer to keep the loss of any bass to a minimum.
I think its a great tone control.

PurpleStrat

It's all going to depend on what circuit you have going in to it. I an't imagine it not having enough treble though.  ???

Download the "Duncan Tone Stack Calculator" to play with the values.

Mark Hammer

Since it is not a boost/cut type, it can only pass whatever treble there is, and cannot increase the amount of treble.

That being said, the treble side of the circuit has a lower bound on the treble portion of the signal, set largely by the .004uf (.0039, actually) cap.  If you make that cap value larger (e.g., .0047uf), the lower boundary of the "treble" starts to move more towards the midrange zone, which for some people will be equated to more bite and "more treble" from their frame of reference.

Alternatively, the 100k pot simply adjusts the relative balance of bass and treble, serving as a mixer.  When the wiper-to-outside-lug resistance going to C1/R2 is greater than the resistance going to the R1/C2 junction, you will hear more bass than treble.  Change the resistance in the other direction, and you hear more treble than bass.  What this suggests is that if you were to insert a fixed resistor between lug '1' on the pot and the R1/C2 junction, the bass would be permanently placed at a kind of disadvantage, relative to the treble, and you would always hear more treble than bass.

Another strategy to try - although you lose adjustability - is to run a cap and fixed resistor (try .0022uf and 12k-18k) from the point labelled "input" directly to the pot wiper.  This provides a bypass for upper treble whose amount will be relatively independent of where you set the tone control.  I say "relatively" because as you rotate the tone control to the treble side, that bypass becomes gradually irrelevent since the treble can pass via the .004uf cap easily.  My advice would be to call it a "treble boost" and use a toggle to enable/disable it.