SuperStack tone control!! My new design..

[dschwartz]

well. finally i designed a nice tonestack (very nice actually) .. it´s active, versatile, with high, mid, low, and mid shift..

is very simple in concept, needs more parts than a regular tone stack, but i´m pleased with simulations..

This is the schem:


some explaining...
as oposed to typical tone controls, the bass control is a variable high pass, the pot controls the rolloff, at max it rolls off at 20Hz, and at min it rolls off at 1Khz (WAY effective!), the  treble control is a variable low pass, at max it rolls off higher than 10Khz, and at min it rolls off at 1.5kHz..

The mid control is a scoop filter, (thanks STM), it cuts mids around 800Khz, and the shift control moves the scoop between 400Hz and 1kHz

So, it affects the freqs that we want to affect, without any interaction
The tone loss of the passive net is really low!! less than -1.5dB, If you omit the input buffer, any impedance wil alter the frequency responses..

by the way.. this is a great tone control to add as a pedal!!!

[John Lyons]

So it's not an active tone control. just buffered and with a make up gain stage.
Looks interesting!

john

[aron]

It looks cool to me!!!!!!

[dschwartz]

well.. is not really active.. but it will work like one!! haha

[flo]

Simple and strait forward, I like it! Especially the mid-scoop adjustable mid frequency. 
How would the schematics be if the mid EQ is not a mid-notch but a mid-"hump" version?

[cpnyc23]

nice work daniel!

I know what's going to be on my breadboard this weekend!

-chris

[Ben N]

Simple and strait forward, I like it! Especially the mid-scoop adjustable mid frequency. 
How would the schematics be if the mid EQ is not a mid-notch but a mid-"hump" version?

Not with the passive stack model, but you can simulate it by cutting highs & lows; or I suppose you can put a scoop filter in the feedback loop of the recovery stage and adjust gain for your mid-boost. But that is a different design.

Nice job, Daniel.

[dschwartz]

Simple and strait forward, I like it! Especially the mid-scoop adjustable mid frequency. 
How would the schematics be if the mid EQ is not a mid-notch but a mid-"hump" version?

if you lower the bass and treble, it will give a mid boost around 1.2 kHz..

[dschwartz]

idea!
if you place some diodes here & there, this may work as a very nice distortion

[frank_p]

You are really productive, Daniel... you should put sunglasses on your avatar.

[dschwartz]

hahaha thanks Frank!
i just breadboarded this baby, and put it after a high gain distortion..
my observations:
- sounds great
- it feels like something between a hi fi eq and an amp eq, specially in the way it treat highs.
- i wish the scoop were more pronounced, but it works fine
- bass and treble response is very good, you can feel the hummp going away and the hiss and brightness fading as you turn the knobs
- the mid shift works nice, but obviusly when the mid is scooped..is a scoop shift and not a mid shift.

i am really happy with this, i think i will use it as a standard tonestack for my projects..its unique..

[frank_p]

I am going to put your tonestack in my to do list.  But will not box it.  I might put it on perfboard as a block on my "experimentation surface".

Big Thanks !

[Ben N]

This is the kind of project that would be great to use with a Guv'nor-style outboard loop built into almost any effect (although not with an actual Guv'nor).

[dschwartz]

let´s see if you dig this circuit after you see this frequency response analysis..:

[GibsonGM]

Very nice, Daniel!  Adds some versatility, I know of a few distortions that could use that flexibility....looks like Marshall meets BMP >;o)

[snap]

this shows how effective a low source impedance at the input of a tone control works out!

[gigimarga]

Nice design!

It is possible to use it directly after a Smash Drive?

[dschwartz]

you can use it after almost everything, the input buffer makes it independent of the source...


the only precaution would be not to clip the output opamp, in that case, lower the feedback resistor..

[gigimarga]

Thx for your answer...but my question was unclear: i want to use as a  passive tonestack, without the IC 

[dschwartz]

oh.. then.. i don´t think so..you need that buffer in the input, or you get a lot of tone loss, and frequency responses changes a lot..