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My mini overdrive

5/12/2000 7:20 AM
Hemmo P.	My mini overdrive OK, here´s my LITTLE and SIMPLe overdrive circuit. I toyed with the idea of feedbacking the transistor from collector to base via single diode. (Originally it was intented to create an octave effect with doing the same from emitter) What i got was some neat overdrive. From there I started to bend this circuit and ended up with three transistor-stages and awful lot of feedback and fuzz. But I got back to this original version, cause I´m tweeking my friends wah-wah pedal and got the idea of putting a fuzz with it. So this is what I´m about to do to it: o +9V \| / R1 / \| D1 \| C2 -\|<\|- o---\|\|----o OUT C1 \| \|/ IN o---\|\|-+---\| Q1 \|> \| \| \| GND So C1 is about 0.1 uF(or 2.2uF if you want to make it more fuzz), D1 is 1N4148(or something else you like) R1 is 100K(?) and C2 is 0.1uF. use 2N3904 for Q1(2N5088, my favourite don´t work with this). R1 could be higher for more distortion and lower for more gain. My friend, to whom I´m going to make this plays bass, so this was "designed" for him, but it works with guitar. Try and comment on this. (I just prewieved this message and it looks like c**p so if it looks like that in here then something...) By the way I thought i did something unique by putting the diode in the feedback loop but then after a week of being proud of my 3-trans version I saw the Fet Muff by Jack Orman and that was the biggest reason I´d post this.

5/12/2000 7:20 AM

Hemmo P.

My mini overdrive

OK, here´s my LITTLE and SIMPLe overdrive circuit.
I toyed with the idea of feedbacking the transistor
from collector to base via single diode.
(Originally it was intented to create an octave
effect with doing the same from emitter)
What i got was some neat overdrive.
From there I started to bend this circuit and
ended up with three transistor-stages and awful
lot of feedback and fuzz.
But I got back to this original version, cause
I´m tweeking my friends wah-wah pedal and
got the idea of putting a fuzz with it.
So this is what I´m about to do to it:

 
                  o +9V
 
                  |
 
                  / 
 
                   R1
 
                  /
 
                  |
 
             D1   |   C2
 
            -|<|- o---||----o OUT
 
         C1 |   |/
 
 IN  o---||-+---|  Q1 
 
                |>
 
                 |
 
                 |
 
                 |
 
                GND

So C1 is about 0.1 uF(or 2.2uF if you want to
make it more fuzz), D1 is 1N4148(or something
else you like) R1 is 100K(?) and C2 is 0.1uF.
use 2N3904 for Q1(2N5088, my favourite don´t
work with this). R1 could be higher for more
distortion and lower for more gain.
My friend, to whom I´m going to make this plays
bass, so this was "designed" for him, but it
works with guitar.
Try and comment on this.
(I just prewieved this message and it looks like
c**p so if it looks like that in here then something...)

By the way I thought i did something unique by
putting the diode in the feedback loop but then
after a week of being proud of my 3-trans version
I saw the Fet Muff by Jack Orman and that was
the biggest reason I´d post this.

5/12/2000 2:00 PM

Doug

quote:
"By the way I thought i did something unique by
putting the diode in the feedback loop but then
after a week of being proud of my 3-trans version
I saw the Fet Muff by Jack Orman and that was
the biggest reason I´d post this"

Haha!

Been there myself, thinking I've done something unique, then finding out it's been done before.

FWIW, the big muff uses feedback diodes around a transistor, and the TS-9 uses feedback diodes around an op-amp as well.

But don't let that stop you, minor tweaks can make these circuits sound totally different. In addition, not knowing what's been done before can make for some healthy exploration with a fresh perspective. A lot of good ideas are discovered that way.

Doug

5/12/2000 5:53 PM
aron	Is this a single transistor with a diode from collector to base? For some reason I am having a hard time seeing it.

5/12/2000 9:40 PM
anonymous	Aron, HTML has a way of making a mess out of ascii diagrams. This can be avoided by enclosing the diagram in a pair of <PRE></PRE> tags. I edited Hemmo's message to include the tags, so it displays as it should now. --tboy

5/13/2000 12:06 AM
aron	Re: My mini overdrive - OK I C it! OK, this looks like Joe's simple overdrive version 1 and/or maybe a single stage of a big muff except it's missing one diode - does it sound asymmetrical?

5/15/2000 7:02 AM
Hemmo P.	(How can you edit text from previous message here?) It may look like Joe´s SOD or Big Muff but I tried it with two diodes and it don´t work that way! It certainly does the trick, i´ll say. The sound is pretty neat, so I´ll guess it is symmetrical. I got some weird clipping there by putting two of these in series!! And then softed it out by replacing a diode from the another stage I added in the end, a 220K resistor. Also added a emitter follower(unique one; emitter to +Vc!)Made one for my friend, the one who plays bass and he said it´s good. So this is totally my own inventment(did i spell it correctly?) And thanks tboy for fitting the schematic

5/15/2000 7:02 AM

Hemmo P.

(How can you edit text from previous message
here?)

It may look like Joe´s SOD or Big Muff but I
tried it with two diodes and it don´t work that
way!
It certainly does the trick, i´ll say.
The sound is pretty neat, so I´ll guess it is
symmetrical.
I got some weird clipping there by putting two
of these in series!! And then softed it out
by replacing a diode from the another stage I
added in the end, a 220K resistor.
Also added a emitter follower(unique one; emitter
to +Vc!)Made one for my friend, the one who plays
bass and he said it´s good.
So this is totally my own inventment(did i spell
it correctly?)
And thanks tboy for fitting the schematic

5/16/2000 9:37 AM
Hemmo P.	Ok, I posted the schematic of the three transistor version on the net for everybody to see if wants. address; http://www.angelfire.com/ga3/sitruuna/distomy.jpg This does work only with stratocaster. I´ll be sending the "Les Paul" version soon. (also some "never-seen" things like Ibanez Black Noise and Nobel´s distortion)

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