Boss Turbo Overdrive OD-2

[Krinor]

I have recently aquired an old and battered Boss OD-2 which was just laying around. Now as it happens it is still just laying around, waiting for some fabulous mod that will make it slightly more acceptable. Does anyone here have suggestions as to what needs to be done ? (I realize that this might give rise to some mirth in the vein of for instance:"throw it in the junk - imediately" or "Jump on it - then throw it in the junk"  )

[aab0mb]

http://www.freeinfosociety.com/electronics/schemview.php?id=162
What don't you like about it?  What are you looking to get out of this pedal?

[Toney]

I thought it was 'ok'... I was ready to pass it on after a few days.
Then I tried it with a Tele....you might be surprized! 

[Krinor]

Ah... Well I need to try that then.

[wampcat1]

possible mods, mess with the lp filter, r48, c32
r35, c22 HP filter
r33, c25 mess with gain on turbo
c31, mess with input cap on overdrive
r47, c30 mess with combo for gain structure, more/less gain on od
d9, d10, d11 diode changes
c35 output cap for turbo
c4/c5 final output cap (c5 affects bypass too)
c33 input cap on turbo

I'd start with those and experiment
bw

[burnt fingers]

That's a great pedal. i used one for years in stock form. Don't trash it. 

You may find some mods that will chang the sound a bit but really I think it's a great pedal.

Scott

[jhamnett]

possible mods, mess with the lp filter, r48, c32
r35, c22 HP filter
r33, c25 mess with gain on turbo
c31, mess with input cap on overdrive
r47, c30 mess with combo for gain structure, more/less gain on od
d9, d10, d11 diode changes
c35 output cap for turbo
c4/c5 final output cap (c5 affects bypass too)
c33 input cap on turbo

I'd start with those and experiment
bw

I thought my OD-2r was trash before the IndyGuitarist mods... now I love it!  Much nicer clipping and sound.

[wampcat1]

possible mods, mess with the lp filter, r48, c32
r35, c22 HP filter
r33, c25 mess with gain on turbo
c31, mess with input cap on overdrive
r47, c30 mess with combo for gain structure, more/less gain on od
d9, d10, d11 diode changes
c35 output cap for turbo
c4/c5 final output cap (c5 affects bypass too)
c33 input cap on turbo

I'd start with those and experiment
bw

I thought my OD-2r was trash before the IndyGuitarist mods... now I love it!  Much nicer clipping and sound.

thanks!

bw

[Krinor]

possible mods, mess with the lp filter, r48, c32
r35, c22 HP filter
r33, c25 mess with gain on turbo
c31, mess with input cap on overdrive
r47, c30 mess with combo for gain structure, more/less gain on od
d9, d10, d11 diode changes
c35 output cap for turbo
c4/c5 final output cap (c5 affects bypass too)
c33 input cap on turbo

I'd start with those and experiment

Wow! Thanks alot.  I wish weekends were longer...

[aab0mb]

Thanks Wampcat!  I've read and or posted a few things about this pedal but i think these tips should keep people happy for a while.  I love the ideas about tweaking the turbo section.  Just threw in some 4001s for the clippers with good result.  I'll be trying some of these options soon.  Does anyone know if this pedal is closely related to any other pedals?

[aab0mb]

"r33, c25 mess with gain on turbo"

I suspect that you mean r38,c25 on the Free Info scheme.  There appears to be an inconsistency in the type on the page for "r38" that could make it appear as "r33".

r38,c25 seemed to make more sense to me.

Correct me if I'm wrong. 

Aaron

[aab0mb]

Why does this pedal suffer from low output? 

If I had two Si diodes per side for a higher forward voltage and more volume would I want to adjust gain proportionally to the forward voltage adjustment in order to keep the drive knob's function roughly the same?

[MR COFFEE]

Some of the classic rocker types really dig it.

Does anyone know if this pedal is closely related to any other pedals?

Depends on what you call "close". Uses JFET discrete op amps as used in several Boss designs. Check  out the BD-2. OD-2 was one of the first Boss pedals to use that circuit IIRC.

I kinda like the "Turbo mode" sound myself.

@Krinor

What don't you like about it?  What are you looking to get out of this pedal?

Ditto. You'll probably get more helpful responses from folks if you are more specific about what you want .

[Melanhead]

A friend dropped one off for me to mod just thought I'd share:

Basically I looked at all the areas I thought I could play with,  and they are the same areas Brian had mentioned above ... I didn't however change the clipping diodes ...

When I first listened to it, I found it dull and lacking low end so I went about it with the goal of improving clarity and adding lows.

here's what I did:

C1 - .047uf
C31 - .1uf
C33 - .1uf
C5 - 1uf
C4 - 1uf
R47 - 1.8K
r48 - 5.6k
C22 - 51pf

enjoy ...

[Mark Hammer]

You might want to look at the schematic of the ROD-10 for some ideas: http://img.photobucket.com/albums/v474/mhammer/ROD-10.png

Several of the various distortion voices use the same basic discrete op-amp structure.  I'm not saying the ROD-10 is the be-all and end-all (I have one and can vouch for that) but it does utilize the same topography in enough ways to illustrate principles you can apply elsewhere.

It will also be useful to check out any of Jay Doyle various variations on the same theme (Touch of Sweetness, et al).

[Melanhead]

Thanks for the tip Mark! ...

I'll have a peak ...

[aab0mb]

Did anyone have a look at the mods I posted here for the OD2 turbo section?
http://www.diystompboxes.com/smfforum/index.php?topic=62702.0
It's a little something different.  I'd be very interested to know what you all think about the idea/mod.  Gotta love the discrete opamp stuff. 

[cab42]

I have one as well, my first stompbox. I haven't used it for years. A couple of nights ago one of the other guitarists in our company christmas party band borrowed it and it sounded better than I remembered. But Melanhead is right, it lacked some bottom end!

The only thing I have done to mine is adding an external  footswitch for the turbo knob, which I have found quite handy!

Regards

Carsten

[roseblood11]

Has someone got a layout for the OD-2?

[Paulo Shure]

GREETINGS to all : What to do to add more gain this pedal  Od-2 drive?