New Overdrive circuit made by me! Need some feedback(no pun)

[sir_modulus]

Ah the wonder of the "Ten Year Old Sandwich Fuzz", a three segment very standard Opamp based soft diode clipper. What do you guys think? any improvements, suggestion, critism (good)?

Here it is:
http://img.photobucket.com/albums/v439/sir_modulus/TYOS1.gif

P.S. note that the image is HUGE (anyone know how to resisze a gif?)

Thanks!!!

[RDV]

What's it sound like?

When you want to resize a GIF, one way is 2 save as a jpeg, then you can resize with typical photo editing software. In this case I saved it as a bitmap with MS Paint, then opened it and resized with MS Photoeditor, then opened the bitmap with paint and saved as a GIF again.

RDV

[Marcos - Munky]

Looks fine for me. Maybe with a good 3-band EQ you get a cool overdrive. The three gain pots looks like it~s a versatile unit. You have soundclips:

[Ansil]

i am resizing it for you will put it on photobucket so you can copy it and reloadit to yours







i dropped it straight into pbrush hit resize 50/50  save as tyozfuzz.gif

[cd]

You should put some EQing in between stages, as is it will likely sound noisy and/or harsh.  Try increasing the the 50pf caps.

[sir_modulus]

k will do. Adding the baxendall 3 band using the remaining half of an OA. now my other question. If I max out all the controls, I'm going to get three OA with gains of 251 each. Is this too much?

[cd]

f I max out all the controls, I'm going to get three OA with gains of 251 each. Is this too much?

Nope, you've got the diodes there clamping the signal.  Depending on your layout/wire routing, it could still oscillate though.

[Peter Snowberg]

Since everything is DC coupled between the stages, you can eliminate the two 1M resistors that feed Vr to stages 2 and 3. The other option is to add some 10uF coupling caps between the stages.

Looks very cool!

[brett]

Hi. It's an interesting idea to use Ge then Si then LEDs to clip.  I haven't thought it through, but would a 4PDT let you switch the Ges and LEDs around?  ie LEDs first?

[sir_modulus]

that'd be real hard....I'll think and see if I can find a way (a barely have enough money to afford 1 3PDT per box, let alone 1 3PDT and 1 4PDT per box. I could make it in a later version that you have three rotary switches to decide which clippers to use each stage, I'll post the rev 2 schematic sometime tomorrow.

[David]

...  nice work, Sir Mod!  I think you're on to something!

Are you fishing for ideas?  I actually have a couple.  Try these:

JFET input buffer before op-amp 1 (I know, it's actually redundant, but it could help give you that tube vibe...)

Capability of switching between bridged diodes (soft clipping) and diode pair to ground (hard clipping) in first stage.  I would think this is the one you want to pound.

Converting that last stage from a distortion stage to a tone control stage.

Where does the "three year old sandwich" thing come from?

[sir_modulus]

The new TYOS fuzz is almost ready (I added a bunch of new stuff including an active 3 band EQ, LPB output buffer(thats a whole LPB right on the output folks!), etc...) I'll post it tommorow when it's ready.

Till then, bye and Thanks for the input (no pun intented),

[Brian Marshall]

the big thing that i see that might be a problem is low frequencies.

since you have giant caps followed by large resistors on the input and output.  it will not attenuate any low frequencies, at least not in the audio range.  this is a recipe for muddieness.  you also might want to lower the the cap values to ground in your feedback loops, especially in the first stage.

[bwanasonic]

Looking at this makes me envisage a LEGO-like fuzz construction toy, with little modular fuzz/distortion building blocks. I have vague memories of an electronic construction set when I was kid that had little blocks with electronic schematic symbols on top that you could arrange into various circuits. Kind of a LEGO meets 200-in-1 electronic projects kit thingy.  Now I see Germanium mutated Gameboy cartridges...

Kerry M

[cd]

Have you built/breadboarded this thing, or is it all theoretical at this point?  If the latter, breadboard the circuit at least and actually play into the thing - you'll get a better feel for clipping and different topologies.

[sir_modulus]

it's concept but read the new post. Thats the new circuit. I'll build that one on pad per hole board.

[Mike Burgundy]

Bwana:

Looking at this makes me envisage a LEGO-like fuzz construction toy, with little modular fuzz/distortion building blocks.

Have a look here:
http://www.geofex.com/Article_Folders/FXbus/fxbus.htm

[WGTP]

Check out the post about Mosfet clippers.