Built a synthy fuzz

jucas · #1 01-07-2010, 11:28 PM

Well, I don't buy many pedals anymore so you all get to put up with threads when I build something that I think sounds good. (its the one thats got some fake wood on it)

This one's a synthy, gated fuzz that is amazing on bass. It combines tim escobedo's simple square wave shaper, and pulse width modulator with a couple minor changes to make them work together. It runs from gated to raging and open, from harsh to bassy. Lots of synthy textures to be found, and it takes a filter well. The gating is better than on the simple square wave shaper I built. Less splattery on the trails, but there's still some fizz. I can get some pretty mammoth-ish sounds out of it too. Its not going to be dead on, but in the ballpark with some more versatility. Totally unrelated circuit by the by.

If I want it too, it can get REALLY bassy... even through my tiny cab. With my 5 string fretless, I can make an open low B sound like it was played on a square wave octaver. I put this together a month or two ago, and still am finding new sounds in it... I love it.

The clip here is quick and dirty with some static and volume changes... Its called wood. Starts clean, then blueberry, then harsh fuzz, then with a blueberry to tame it after. Then I change some of the settings, a noodle randomly a bit at the end. Lots of frequencies, and a volume drop in the middle, so decent speakers or headphones are going to show the diferences better. And as always this is direct so its not this harsh through a cab.

Here's a schematic and the test rig. I'll put up some more clips with the five string, and better demo of what the controls do as soon as I can, but I ran out of time tonight. (also a better schematic after I fill in values and scan it. If you want to though, you can figure it out from here pretty easily)

For those that might build it, I went with 12V, but it ought to work at nine. if you run the schmitt trigger off a lower voltage than the opamp(I think it needs 5 or 6 minimum though) the gate is a bit smoother, and the sustain is better. So, we "square" the signal and can change the duty cycle for pinched off tighter sounds. And, we can change the rise and fall time of that output which kinda lowpasses, but changed the texture of the fuzz too.

nad · #2 01-08-2010, 12:00 AM

Sounds wild, I can dig it. That bit around 1:11 is great.

fightthepower · #3 01-08-2010, 12:28 AM

Sounds a like a cross between the Devi Bass Fuzz and Freqbox square/pulse+PWM, with a leaning towards the Devi Bass Fuzz. It sounds great, nice work!

jmorbita · #4 01-08-2010, 06:43 AM

Nice!!!

jucas · #5 01-08-2010, 07:20 AM

Thanks! I'm pretty happy with the way it turned out and I'm going to eventually use it as the basis of a synthy board on a PT mini.

Mr. Pickles · #6 01-08-2010, 08:18 AM

how's the Godin?

JohnDavisNYC · #7 01-08-2010, 10:26 AM

that sounds great! really really great! might have to build one or have a friend who is not as retarded as i am make one....

great sounding pedal.

john

jrmy · #8 01-08-2010, 10:37 AM

Wow! That is sweet. Do you have any plans to make more of these for sale?

Valerus · #9 01-08-2010, 11:03 AM

Sexy

Pitbull Growl · #10 01-08-2010, 11:14 AM

Pretty sick jucas.

How well does it handle active instruments/buffers?

JohnDavisNYC · #11 01-08-2010, 11:16 AM

good point... would be great to hear it after, say... an oc2????

or really, any boss buffer will tell me what it'll do with the oc2...

john

rcubed · #12 01-08-2010, 11:52 AM

Interesting idea. The pots controlling how much signal gets clipped through which diode is a cool idea.

jucas · #13 01-08-2010, 05:22 PM

Fine after a buffer, no issues there.

No plans to build them, but I hadn't really thought about it.

I can't take credit for 95% of the design, I just pasted and refined a bit.

And, I love the godin, but its pretty deep with flats or tapewounds, rounds'd be nice but I don't want to chew up the board too much. The B is a bit loose, but I make do with it.

JimmyM · #14 01-08-2010, 11:56 PM

even though i really have no practical use for one at the moment, that thing sounds so good in those clips that i could be talked into buying one if someone made it at a reasonable price.

jucas · #15 01-10-2010, 10:57 PM

Quote:

Originally Posted by rcubed

Interesting idea. The pots controlling how much signal gets clipped through which diode is a cool idea.

I might be mistaken, but I thought that it wasn't so much a clipping thing with the diodes, but more separating the positive and negative swings and using the resistor to control the slew rate with the cap to ground. (although, I also remember reading somwhere that the transition time between high and low states on a schmitt trigger isn't actually called slew rate... I just can't remember the right term)

Quote:

Originally Posted by JimmyM

even though i really have no practical use for one at the moment, that thing sounds so good in those clips that i could be talked into buying one if someone made it at a reasonable price.

And that clip is just barely starting to scratch the surface of the sounds in there. I didn't adjust the duty cycle control much at all for it.

Taylor Livingston · #16 01-11-2010, 03:17 AM

Quote:

Originally Posted by jucas

I might be mistaken, but I thought that it wasn't so much a clipping thing with the diodes, but more separating the positive and negative swings and using the resistor to control the slew rate with the cap to ground. (although, I also remember reading somwhere that the transition time between high and low states on a schmitt trigger isn't actually called slew rate... I just can't remember the right term)

Yep, although you removed the actual square wave shaper from the square wave shaper. The diodes split the pos and neg and control how much each gets filtered. This lets you shape the square into saw-ish and triangle-ish waves.

jucas · #17 01-12-2010, 12:13 AM

Well, more bumping because I made a clip with the fretless five string. Its pretty aimless and kinda long, but shows some low notes, some high notes, a few more pulse width changes than the last one, and my aimless meandering on a fretless. I know how badly everyone wanted to hear that.

wood2

I still don't know what the random high pitched background noise in all my recordings is.

PS... There's also a really bad one on the guitar on the main page. Its for a build thread at DIYstompboxes after I fill in the blanks in the schematic but incase anyone cared for some reason, there it is...

jucas · #18 06-12-2011, 01:40 PM

Well, a long time later, here's a schematic and layout since someone asked me about it by PM.

Still a great fuzz, although it could probably be refined a bit now that I know a little more. But, this is the version I made and it sounds good as is.

pwm1.xls

Attatchment is a rough bill of materials. It shoud be fairly complete, but I could have missed something.

Gopher Bob · #19 06-15-2011, 08:12 PM

Very cool... I may just have to check youtube to see if there are any pedal making videos out there.

zktui · #20 06-23-2011, 03:19 AM

As I am currently buying the parts to make this, I've encountered a couple of hitches. Does anybody know what kind of pots I need? Just a normal linear one or does it need to be log? (sorry if this is a silly question)
Also, with the pots 500k's are harder to get in stores where I am, could I instead use, say, 3x 100k and 1x50k (or just all 100k or something?)

Cheers