why doesn't anyone use this for tone control?

[pinkjimiphoton]

i'm building a suzy q for dick wagner. (suzy q is a fuzz i cobbled together, search for it if interested). i didn't add a tone control to the original, cuz i didn't feel it needed it.
but i want the man to be happy, and actually use the freekin' thing, so i asked for his preference...tone control, or not?
he said he prefers a tone control on the pedal.
so i set out to add a tone control to it.
i immediately thought of the stupidly wonderful tone control mark hammer designed, and decided to try it.
i know, i mean KNOW, i'm stupid, but i couldn't get it to play well with this circuit. it only really worked if i put it in series after the volume control.
i didn't want that..
so i tried a BMP style. didn't do the trick either. just didn't wanna play nice..lost a lot of "edge".

so i thought back to my simple-ass stiff hippy overdriver, a 386 based od based on culturejam's dead easy dirt. on that,  i found a "pre" tone control (in parallel with the input of the effect board) worked great.

so i figured, in for a dollar...

i took a 50k pot, ran a jumper from the wiper of the volume pot to the input of my new tone pot. experimented with caps, and found a  .0047u cap from wiper to ground did the trick. just to be sure, i put a dpdt switch in to see how much tone suck i'd get.

but here's the thing... i didn't get any (perceptable, at least) tone suck at all. it does just what i wanted, it shaves off the treble without making it muddy, sucking volume or sucking tone.

i mean, for all intents, it's wired like a freaking guitar tone control.
i took the switch out cuz it didn't need it. i could hear no diff with the tone control all the way up and when it was true bypassed.

so, my question, after reading hundreds of threads about volume drop from tone controls etc, why the heck doesn't anyone just use a tone control the way i did?
i mean, it works, it has minimal if any effect on the volume of the pedal, and unless turned down, doesn't make any difference to the pedal tone...

ideas? am i crazy?
anybody else do this? i mean, this is the stupidest pedal trick of all, and the simplest tone control...

[brett]

Hi. Any chance of drawing a picture?
Regarding a BMP tone section not working - it needs a low output impedance device before it (pickups/volume control are high) and a high input impedance after it (IIRC, a 386 is low). That's why the tone section is followed by a buffer in the BMP.
cheers 

[pappasmurfsharem]

I'm confused JIMI you state

it only really worked if i put it in series after the volume control.
i didn't want that..

Then

i took a 50k pot, ran a jumper from the wiper of the volume pot to the input of my new tone pot. experimented with caps, and found a  .0047u cap from wiper to ground did the trick. just to be sure, i put a dpdt switch in to see how much tone suck i'd get.

So you ended up running it in series after the volume control after all?

[GGBB]

I believe part of the reason for tone sucking by the traditional guitar passive vol/tone setup is the interaction between it and the pickup - specifically (again I *think*) the inductance.  Now, I have no idea what the inductance is in the fuzz circuit, but maybe it's considerably different (less? negligible?).  Other factors maybe - your pot-cap is 50K-4n7 versus typical guitar 250k/500K-22n.

[Mark Hammer]

Wait, THE Dick Wagner?

[armdnrdy]

Half of the "Nightmare" dynamic duo?

Ezrin's "go to" guy?

Yeah....I recognized the name because I'm "old" too! 

[Gus]

Draw and post the circuit.  That will help.

[pinkjimiphoton]

I'm confused JIMI you state

it only really worked if i put it in series after the volume control.
i didn't want that..

Then

i took a 50k pot, ran a jumper from the wiper of the volume pot to the input of my new tone pot. experimented with caps, and found a  .0047u cap from wiper to ground did the trick. just to be sure, i put a dpdt switch in to see how much tone suck i'd get.

So you ended up running it in series after the volume control after all?

nope. the tone control is in parallel, like inside a guitar. works great. no tone suck, no volume loss. like i said, i a/b'd it with a true bypass, and with the knob cranked, could discern no difference with the tone control in or out of the circuit.

and it's crazy simple. two parts.

a pot and a cap.
ground the cap right to the back of the pot from the wiper (pin 2)

[pinkjimiphoton]

guys, THE dick wagner.
there's only one.

the circuit is my suzy q. rev 6, in this thread:

http://www.diystompboxes.com/smfforum/index.php?topic=101178.60

here's a link to tagboard:

http://tagboardeffects.blogspot.com/2013/02/jimi-photon-suzy-q-mkii.html


you want me to draw a pic? will upload shortly, but again, all it is is a piece of wire from the jumper of the output volume pot to pin 3 of a 50k pot. .0047u cap from wiper of 50k pot to ground (on the back of it)

i'll be back with a drawing later.

[pappasmurfsharem]

Ahh ok so you still have your output coming from wiper off the volume. Then have basically have a VR and cap to ground connected at the same junction

Hypothetically wouldn't that mean changing the volume would also change the tone as it adds more resistance?

[pinkjimiphoton]

doesn't seem to. weird!
just like on a guitar, tho, if your cap's not too big on your tone control, you don't lose volume when you turn 'em down (tho you do lose a little volume and sparkle with the load of the pots on a guitar).

i mean, i WAS gonna add a switch, but it just seems like overkill. this just kinda takes the treble off and not much else.

[pinkjimiphoton]

here's the newest schematic.
as you can see, it's the stupidest little add on, but it seems to work great.

[armdnrdy]

It seems like the "normal" place to put the tone section would be between the clipping diodes and the second mosfet.

But if it works?   

[pinkjimiphoton]

here's a really bad 2 minute demo i did for mr. wagner...

[Keppy]

The OCD uses a similar arrangement, with two differences:
1) The pot and the cap switch places, which should make no difference.
2) The pot/cap combo comes from lug 3 of the volume pot, not the wiper.

I don't know why this isn't more popular. It's a nice, easy arrangement.

[Devius]

wouldn't the same tone circuit be found in a guitar?

[Thecomedian]

You're talking about permutations of tone controls. There's millions of them in theory. The original fuzz was temperamental, and people went through testing tons of the units before finding the "sweet one". Now we know what makes the sound better or worse, weak or focused, etc.

[pinkjimiphoton]

wouldn't the same tone circuit be found in a guitar?

yep, exactly.

[brett]

Hi
Rd = 100k on Q3 creates high output impedance (just like a pickup) and makes the whole thing work.
It must be plugged into a high Z pedal or amp or there'll be signal and tone suck.
cheers

[pinkjimiphoton]

thanks brett,
so..  how do i determine the impedance? just measure across the output jack of the circuit?

seems to work fine on guitar amps, no tone suck or attenuation to speak of, at least not when the tone control is cranked.
like i said, i put it on a switch to try both ways, and it really didn't make any audible difference.

i'd imagine any guitar amp or pedal should work out ok... maybe i should add that switch back in?