Finished...AMZ Overdrive Pro !!!!!!!!!!

[petemoore]

The Name says it All.
 I spliced a gain recovery stage between the tone/volume pots using  the second half of a dual OA, thanks for the suggestion RDV. I used a 10k trimpot before the GR stage, just in case, doesn't do much and isn't necessary.
 I ran out of 1 megs, but used a 400k...[ala dyna preamp], I'll probably just solder values of fixed resistors to it's ears 'till it gets well past both ends of the range I might use...below unity/well above unity.
 I like the many ways it works.  Quite a powerful pedal. A BC109 for Q1...[if you like BC's in gain stage, I do], I tried a 2n2222, and that changed the character too.
 Thanks to Jack Orman at AMZ, this is going to be very nice pedal to have around.
 Gobs of gain, Plenty of power in reserve, highly variable Overdrive sounds...Overdrive Pro!

[RDV]

SWEEET!!

RDV

[stumper1]

Looking for some (lots) of help with this.  Built the Overdrive Pro and really dig it so far.  Tried LED's and the output was fine.  Swapped out for diodes and the decay of the signal sounds much better but output is lacking.  Used the layout at Tonepad (thanks) to make the PCB.

Can anyone help with basic (very) step by step instructions for the Gain Recovery stage?

:?

Thanks,
Deric

[bass_econo]

I tried a 2n2222, and that changed the character too.
 

Pete how much difference did the 2N2222 make?  It seems to be unliked in most circuits.

[RDV]

Can anyone help with basic (very) step by step instructions for the Gain Recovery stage?

RDV

[stumper1]

RDV -

Thanks!!!  That's just what I'm looking for.  I do have a couple of questions.  Looking at the schematic, the GR stage is fed from the middle lug of the Mid control.  I use pins 1,2 and 3 of the Opamp for the GR stage and then replace the existing 1M Vol pot with a 100k.  Is this correct?

Also, I can see that I need to cut the traces on the board between pins 1-2 and between pins 3-4.  From there I am not sure of which pins are the B,C,E in your schematic.

Thanks for the help! :oops:

[Doug_H]

Pete how much difference did the 2N2222 make?  It seems to be unliked in most circuits.

Huh?!? :?:

Doug

[RDV]

RDV -

Thanks!!!  That's just what I'm looking for.  I do have a couple of questions.  Looking at the schematic, the GR stage is fed from the middle lug of the Mid control.  I use pins 1,2 and 3 of the Opamp for the GR stage and then replace the existing 1M Vol pot with a 100k.  Is this correct?

Also, I can see that I need to cut the traces on the board between pins 1-2 and between pins 3-4.  From there I am not sure of which pins are the B,C,E in your schematic.

Thanks for the help! :oops:

Maybe this is more what you're looking for then.


RDV

[bass_econo]

Pete how much difference did the 2N2222 make?  It seems to be unliked in most circuits.

Huh?!? :?:

Doug

It seems that whenever the 2N2222 is brought up everyone talks about how terrible it is and Pete said he tried one and it had it's own character.  I guess I was asking for an elaboration on the character.

[stumper1]

Maybe this is more what you're looking for then.

EXACTLY!!!!

Thanks!!

[aron]

I love the metal can 2N2222!

[Doug_H]

I love the metal can 2N2222!

Me too!

Doug

[WGTP]

Try an LED/SI diode combo and maybe you won't need the recovery stage.  

[RDV]

Try an LED/SI diode combo and maybe you won't need the recovery stage.  

Howzabout both? :twisted:  :twisted:

RDV

[WGTP]

Now that I think, the Rat I rebuilt had 4 SI's, 2 going each direction.  

Many possible combination that would result in higher clipping threshold than 2 SI's and lower than 2 LED's.  

[stumper1]

I tried 2 LED's, 2 diodes, 1 LED/1 diode.  Of those so far I liked the 2 diodes the best.  I didn't try any other combos yet.

Thanks for the tips.  I'll definately give it a try!!!