Controfuzz!!!

[Mark Hammer]

Back in the early days of this "community", Jamie Heilman's "Leper's Archive" was pretty much it for schematics, and a great many were drawn and traced by RG and Jack.  

One of the posted schematics was for the Gretsch Controfuzz.  This is a wacky beast that mixes a fuzz and straight signal, but not in the way you'd think and certainly not the way they are combined in something like the Voodoo Labs Sparkle Drive.

Instead the Controfuzz allows the dry signal to cancel out chunks of the fuzz signal.  Because the decay of the fuzzed signal takes longer to occur than the straight signal (that IS why some folks like to use distortions, right?), what happens is that the fuzzed signal becomes MORE prominent as time passes and the straight signal decays.

Interesting sound, though certainly not the sort of general purpose leave-it-on distortion most would prefer using (and probably a reason why they didn't sell and tend not to command lofty prices on the vintage market).

Thought the original was not apt to draw players to it like sailors to sirenes, there are some interesting properties that are worth tinkering with.  The most interesting is that the Controfuzz tends to acquire MORE audible harmonic content over the duration of the note, rather than less.    It also made the Controfuzz one of the first sort of "morphing" effects since it would gradually transform from a largely clean signal to a fuzzier one, in contrast to fuzzes that petered out.

This is important because it makes dynamic filtering more potentially interesting.  For instance, suppose you had an envelope controlled phaser.  Strum a note/chord and the phaser sweeps; maybe up maybe down.  Since the harmonic content *decreases* over time, there is actually less opportunity to hear the effect of whatever notches are introduced by the phase shifting as the note sustains.  In the case of the controfuzz-type effect, the harmonic content increases over time such that as an envelope-controlled phaser or flanger "settles", there is still something to filter.

In any event, I thought I'd just put that idea out there for folks to start thinking about, and to introduce a little lateral thinking for the week.  We spend lots of time thinking about what to do to maintain clipping of a note over more of its duration, and plenty of time thinking about the dynamic filtering of things that are already clipped, but precious little time thinking about things that get MORE clipped over a note cycle.

[puretube]

you`re not alone... :wink:

[R.G.]

The Controfuzz piqued my curiousity a while back and sent me off on one  of my mental development efforts.

I thought it would be interesting and a bit more natural sounding (in an unnatural way, of course) to take a guitar signal and
(1) compress it to a constant level during substantially the entire note
(2) clip the compressed signal
(3) impress the original envelope on the compressed and clipped signal

What you ought to get is a signal that is distorted, but has an even amount of distortion over varying parts of the envelope. That is much more like what simplistic synths do than what guitar clippers do. The harmonic content is more even, and independent of the instantaneous loudness.

It always sounded like something that needed done, if only as an experiments. I was going to lash up one of these from the FxBus modules.

[puretube]

R.G.:
that`s the way it`s done in the E-H "Graphic Fuzz" (with equalizer section afterwards),
and in the E-H "Micro Synth",
and what I was referring to in principle in 2nd post here:
http://diystompboxes.com/sboxforum/viewtopic.php?t=22751&highlight=
(freq. contolled oscillator)

Mark is after another sound however: he wants it to "evolve"...

Got a nice new thingy on the workbench, which does some envelope-dependant-pulsewidth-movement, which also is not what Mark is talking about, but it does do some nice "walk thru the harmonics" over time
like a phasered fuzz...

[Nasse]

Just wonder if few old fuzz sicko box circuits are worth looking in this context, think there is something similar in ETI "Hyperfuzz" and Elektor "Sound Effects Generator" (Year 1980? or so). Both use opamps sum/difference and diode clipping somewhat like Controfuzz but much more complicated circuits... that Hyperfuzz sure is capable over 100% distortion :wink:

[StephenGiles]

That sound very interesting Puretube - reminds me of the time I listened to Joe Truchess develop the EH Space Drum!

[Paul Marossy]

I don't suppose there is a soundlip floating around for this one, is there? Sounds like an interesting effect from your description.

[Paul Perry (Frostwave)]

Got a nice new thingy on the workbench, which does some envelope-dependant-pulsewidth-movement, ...

this is nice (assuming it is a comparator with envelope to one input). A good thing is that you dont have to be overfussy about the envelope filtering. And, for a bonus, use the envelope to amplitude modulate the output from the comparator, to put the dynamics back in. Oh and the octave down divider after the comparator.. SHIT, ran out of knobs :lol: