2 stage IC Fuzz

[arawn]

I wonder if this would work?? Does anyone see anything wrong with the way I have it wired??
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By arawngwydion at 2007-08-02[/url]

[theonlyrobkeyser]

I can't seem to open any of those links and get an image that's large enough to really look at.

[arawn]

okay try this one http://s200.photobucket.com/albums/aa266/arawngwydion/

[arawn]

or we can try this

[theonlyrobkeyser]

I'm no expert, but if your going into the inverted and non inverted inputs with the same signal, won't they cancel each other out?

Other than that I don't see anything that would make it not work, but you may want to make some changes to optimize it's sound.

[arawn]

Basically I'm looking for suggestions this is loosely based on a fuzz i saw at ss guitars And i don't know who to credit for it but the fuzz there is a single 386 with no pots or trimmers just a few caps. I was trying to get a very simplified version of a multi stage fuzz

[Cardboard Tube Samurai]

Try throwing caps C1 and/or C2 across the two inputs of the op-amps for a slight octave effect. Have you got this one working? I was going to breadboard something similar this weekend funnily enough but hadn't got to figuring out how to work the gain... you have given me some ideas there!

[ambulancevoice]

you need to ground pin 2
and just use input three
also, are the diodes intended to be clipping diodes?

[arawn]

yeah the diodes are intended for clipping, no i haven't built this yet I have to get the pots, but i want to hear what it sounds like. I like the idea of a slight octave, I missed that but i still pretty new at this>

[Cardboard Tube Samurai]

The clipping diodes need to be grounded

[arawn]

so it should be a little more like this ??

[Cardboard Tube Samurai]

Pretty much, yup!

[ambulancevoice]

the diodes wont clip at all if you dont ground them
this is how they can be configured
(the one with four diodes will clip more)


also, id really really clean up that layout too
i can barely tell whats going on

[Cardboard Tube Samurai]

I would also suggest that you put a volume/level pot over the whole circuit too. I use a 100k log for this. (Reading from right to left when looking at the bottom of the pot) Lug 3 to circuit output, lug 2 to switch, lug 1 to ground.

I'm no expert, but if your going into the inverted and non inverted inputs with the same signal, won't they cancel each other out?

The LM386n has a dual input, hence why putting a cap across them gives the octave effect. It still gives a half decent sound when set up the way he had it in the first diagram, but the slight octave makes for a nicer sound in my opinion.

[ambulancevoice]

also, i would use aluminium electrolytic polarised caps for the output caps

btw, have you built any other pedals already?
or designed and built others of you own before?

[theonlyrobkeyser]

Do the diodes need to be connected directly to ground?  Aren't the clipping diodes in the TS just in the feedback loop of the IC?  I guess the TS diodes are grounded through a resistor and cap on their way to the second IC stage, but I kind of thought that just having two oppositly directed diodes would clip if the signal was high enough.  But, I'm asking because I really don't know and I would like to know. 

[arawn]

Never designed and just started building a couple months ago. The clean boost from here and that ultra simple fuzz http://www.ssguitar.com/index.php?topic=378.0 at the bottom of the page

[ambulancevoice]

Do the diodes need to be connected directly to ground?  Aren't the clipping diodes in the TS just in the feedback loop of the IC?  I guess the TS diodes are grounded through a resistor and cap on their way to the second IC stage, but I kind of thought that just having two oppositly directed diodes would clip if the signal was high enough.  But, I'm asking because I really don't know and I would like to know. 

opamp and the and some transistor fuzzes have the diodes connected in different ways
but output clipping diodes need to be connected to ground in order to clip
unless its crossover distortion

[arawn]

How does this look I took the switch out for now, and does it clarify what I am doing??
gonna bb this tomorrow night.

[Cardboard Tube Samurai]

A couple of pointers... Wiring this up the way you have suggested there WILL NOT WORK! You have grounded the signal straight after the first IC output and again in the same place after the 2nd IC. Try running a jumper wire from the other end of the diodes to ground (where I have indicated with the arrows).