Anyone interested in a chopper fuzz?

[Transmogrifox]

Anyone interested in a chopper fuzz?

I have been working on a simple design that is presently in its early stages of development.  Basically, it's a distortion circuit that switches a coupling cap in series, then bypasses it with a JFET setup similar to the TS and BOSS active bypass circuits.

I use a simple square-wave LFO and add an option of duty-cycle control (this is totally minimum parts).

The distortion itself is based on an LM386 and a 2N7000 MOSFET...very simple, but very nice sounding.  It produces a very smooth fuzz in fuzz mode and a very tight butt-rock to hair metal to all-out thrash metal solid state distortion sound...I think the distortion itself is not bad.

The downside:

1.  Modulating clock feed-through is horrendous on my breadboard.  I know some of it is bread-board/power supply related because the clock ticks in the background even when the Modulating JFET is completely out of the circuit....However, it does get somewhat worse when the FET is connect.  I just don't know how much of the clock feedthrough is coming through the chopper and how much is parasitic from the breadboard setup.

2.  I haven't been able to design an EQ that really sounds good on the output.  The typical amp EQ is not resonant enough and I need to spend some time designing a resonant low and mid boost/cut that does not further distort the signal.  I tried the Danelectro FAB TONE EQ on my breadboard and it was just too "thin" sounding.  It totally dumped the richness of the distortion....

UPSIDE:

Despite the clock feedthrough sound, I consider this to be a very cool sound.  It's like a tremolo that turns on fuzz, then turns on metal when the fuzz is off.

When I get the clock up near 20-30 Hz, the modulation beat frequencies become very audible, and when the clock frequency is low enough in the audio range, the feedthrough is not very noticeable in the background.

This very fast modulation developes a distinct "chorus with rate and depth at max" or even univibe - ey sound.

The distortion itself is very pleasing to me as well.



THE WHOLE POINT OF THIS:

If anyone is interested in building this, even with the clock tick feedthrough problem, I will go through the trouble of drawing up the schemo and posting it.

If not...well...don't reply

[aron]

I think that sounds really cool. So it chops between different types of distortion?

That's cool!

[Transmogrifox]

one taker, eh?  I'll throw it up on the web for that.  

So it chops between different types of distortion?

Yeah.  The two different types of distortion are accomplished by the change in a single coupling capacitor.  It IS amazing the difference between the two.

[keninverse]

I'm Interested...this sounds pretty cool.

[mattv]

Yes, that does sound interesting.

[Jason Stout]

Sounds like my kind of effect :twisted: What is the aprox chop freq range?

[petemoore]

Definitely an interesting concept!!!
 There are a couple details at least he'd like to understand a little better...he thinks this one is worthy of persuit, says you should probably try to grow it [even with the bugs] and see if a hybrid seed can't be designed that doesn't get bothered by those bugs.
 I think the simple fact that no-one's  ever heard of anything quite like this intruiges "m.

[Marcos - Munky]

Looks cool. I like to take a look in the schematic.

[sirkut]

I'm definately interested in seeing this particular circuit, i love out of the ordinary devices.

[Transmogrifox]

I have finished the schematic and just need to plug in a couple of resistor and capacitor values.


I'll have it up this evening when I get back from skiing :twisted:

thank you all for your interest...maybe somebody here will come up with some good ideas based on this concept

[Transmogrifox]

Sounds like my kind of effect  What is the aprox chop freq range?

about 1/4 Hz to opamp instability...usable upper range I'm guessing near 50 Hz...dang it would only take me 10 seconds to calcuate it but i don't have my calculator here right now

[Nasse]

Skiing?

Have you tried "free heels" (or "Telemark" in this side of big water)

[aron]

Sounds like my kind of effect  What is the aprox chop freq range?

about 1/4 Hz to opamp instability...usable upper range I'm guessing near 50 Hz...dang it would only take me 10 seconds to calcuate it but i don't have my calculator here right now

OK, check this out, can you make it chop between 2 external effects? There you GO!!!!!!  :twisted:  :twisted:  :twisted:  :twisted:

[Jason Stout]

OK, check this out, can you make it chop between 2 external effects? There you GO!!!!!!    

Bingo!!!  :wink:

[Transmogrifox]

OK, check this out, can you make it chop between 2 external effects? There you GO!!!!!!

Most certainly.  Either take off my idea I'm using here, or better, pick your favorite tremolo circuit, build two of them and stick the modulating device (LDR, VGA, whatever) at the input of a mixer or your favorite blening circuit, then modulate them with the same LFO, only invert the phase for one of them.  This would be very simple.

I just finished the schematic and I'll have it up in a couple minutes.


Nasse:   I haven't tried any free-heel other than cross country.  I would love to, though>  I have been doing spring skiing in the back country, but would love some teles to go back country more in the winter when the powder is sweet.   I'll tell you what, you buy me some tele skies and I'll build you 10 of your most favorite stompboxes :wink:

[petemoore]

[SLOW ?]... Blend from one type of finely tuned distortion, to another 'counterfrequency' [yet finely tuned] tuned distortions would entail excercizes in modding I think we'd all like. [or Fast]