Boss - BD-2 Blues Driver 1995  [schematic]

All about modern commercial stompbox circuits from Electro Harmonix over MXR, Boss and Ibanez into the nineties.
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sepulchre
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my favorite amplifier: a Fender Twin Amp or a nice Marshall
Completed builds: No way I could remember all of them. Been doing this since the early 80s, but . .
Mostly onboard active guitar preamps, hotrodding amplifiers a bit (mostly tubes), and home brew devices - experiments from my laboratory, mad scientist style.
I've modded and rebuilt some synthesizers, but as far as pedals go I pretty much build my own: overdrives, fuzzes, etc. I've built some software effects like ring modulators, but I'm back into the wires now.
Location: Texas, Arizona, Indiana, etc.

Post by sepulchre »

That's Much better. Thanks!

Ken
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seniorLoco
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Post by seniorLoco »

This Monte guy takes already available mods and puts a copyright on em ....only in Amorika baby :applause:
"Curiosity may have killed the cat, but it saved the mice, who ate the cheese."

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modman
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Post by modman »

seniorLoco wrote:This Monte guy takes already available mods and puts a copyright on em ....only in Amorika baby :applause:
If he puts copyright symbols on the documents he provides with his 'mod kits' that is correct and smart. He made the documents, he owns the copyright. You cannot copyright a modification.

In facts it's just information, and should be able to pass FREELY through the world wide web :mrgreen:
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WhiteKeyHole
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Post by WhiteKeyHole »

modman wrote:These mods look very intersting, WKH!
WhiteKeyHole wrote: C36: .01uF
C35: .047uF
But this is the stock value, no?
Yeah, I don't think I was paying attention there, haha.
modman wrote:
WhiteKeyHole wrote:C34: .44uF :x
:scratch: Why this value specifically?
Again, wasn't really paying attention, this is completely unnecessary.
modman wrote:
WhiteKeyHole wrote:C8: .33uF
C9: Removed :x
You replaced 56nF + 2n2 in series by one 330nF cap?
Yep, C9 removed, defeating the simulated inductor. C8 increased to .33uf to reduce highs.
modman wrote:
WhiteKeyHole wrote:Q9: 2N1303 Germanium
Q12: 2N1303 Germanium
R51: 50K pot (under footswitch to adjust mids for different amps)
This is the craziest part of the mod, I can hardly believe it. What gain ranges did these Ge's have? I suppose high gain low leakage would be a first choice? The Mid pot is impressive as well.
Gains of around 200, low leakage. The difference isn't obvious (to me) until you crank up the gain.

Sorry for the late reply, just noticed your post.

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sidehatch
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Post by sidehatch »

I have a keeley modded BD-2.

I'd like to get more midrange in the pedal to compliment the scooped nature of a BF fender.

I don't want to make it into another tubescreamer though

What would clipping c19 do? I heard that will increase midrange but I dont want to try it until I know more about it.

Can you guys think of something easy to do that will give me a bit more mids but not at the expense of the pedals's tonal properties? I usually run the pedal with the gain from 9 to 1 o'clock and stop after that because of the lack of mids and my Fender amp's accentuating the scooped mids.

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WhiteKeyHole
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Post by WhiteKeyHole »

Increase R51.

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sidehatch
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Post by sidehatch »

What value would you use for R51?

I read on one of the bd2 mod sites to clip c19 for more mids.

Do you have any idea of what that would do versus changing out R51?

Thanks for your help. This is going to be fun. I asked a guy up at Keeley's and he said he didnt know and would have to talk to a tech about it and "why would you want more mids?"

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Post by WhiteKeyHole »

I would leave C19 alone. R51 is part of a fixed Fender style tonestack between the first and second gain block. Try 22K or just go with a 50K trimpot.

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Post by kbibs »

Has anyone ordered the Brent Mason Mod Parts Kit from Indyguitarist? ... I've already made the changes that were listed in Premier Guitar Mag for this mod but I hear that was not complete, in other words the mod consists of changing other parts. Could someone tell me what other parts are changed (not looking for the values just the part designator to the factory schematic) and did those extra parts make a difference? ... the parts I've changed already have improved the overall sound for the better I'm just wondering do these additional part changes make it even better?

Thanks!

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Post by modman »

kbibs wrote:Has anyone ordered the Brent Mason Mod Parts Kit from Indyguitarist? ...
He was so kind to share those here:
viewtopic.php?p=33044#p33044
kbibs wrote:the parts I've changed already have improved the overall sound for the better I'm just wondering do these additional part changes make it even better?
Please have a look at this thread from the start:
viewtopic.php?f=11&t=1062&start=0
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Post by kbibs »

Thanks modman for moving my post as I wasn't sure whether or not to start a new one. I've read this thread many times before and saw where Brian gratiously disclosed the parts he changed for Brent's BD-2 but I've read on other forums that he actually changes more than that. I'm just trying to make sure I don't end up with the same parts I've already modded if I order the kit! ... I'm having trouble registering on his forum for some reason so I thought I would ask here.

Thanks

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Post by modman »

Hey, thanks for the shots, but could you note down the changed part numbers and values?
thanks in advance
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Post by ibzmav »

modman wrote:Hey, thanks for the shots, but could you note down the changed part numbers and values?
thanks in advance
I didn't took the pictures. I just got it through browsing the web :applause:

For more info, just check out keeley's bd-2 page. He explained there what to do.

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Post by Beedoola »

I bought the Allums Blues stack mod kit for my BD-2, this mod is supposed to eliminate the terrible decay of the pedal ,which it SORT of does but not totally. The pedal sounds great but there is still decay..

I have the PDF. if anyone is interested.

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Post by floris »

What's the "terrible decay" in this pedal? Does that mean that while notes are sustaining and dying out (decaying) the overdrive sounds bad?

I'm going to build one soon. PCB is ready, components availabe and I hope it's a nice overdrive.
Currently I'm fond of my Marshall BluesBreaker clone with some mods that I build 6 months ago, but the search for another great tone just never stops! ;)

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sepulchre
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my favorite amplifier: a Fender Twin Amp or a nice Marshall
Completed builds: No way I could remember all of them. Been doing this since the early 80s, but . .
Mostly onboard active guitar preamps, hotrodding amplifiers a bit (mostly tubes), and home brew devices - experiments from my laboratory, mad scientist style.
I've modded and rebuilt some synthesizers, but as far as pedals go I pretty much build my own: overdrives, fuzzes, etc. I've built some software effects like ring modulators, but I'm back into the wires now.
Location: Texas, Arizona, Indiana, etc.

Post by sepulchre »

My Blues Breaker decays just fine. No problem at all. I wish it was a little louder, but there's always the volume knob on my amp for that.
"I love the smell of solder in the morning. Smells like . . . victory."

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Post by eric_idle »

I've read this thread many times before and saw where Brian gratiously disclosed the parts he changed for Brent's BD-2 but I've read on other forums that he actually changes more than that.
You're absolutely correct. Wouldn't it be nice if these guys would just let us know this up front?

I've done the full mod and the parts he leaves off are significant. They do make a big difference
in the sound of the pedal. The free mod Brian gives away doesn't come close to the full version.
He's doing himself a dissercvice, because it gives one the impression that his mods aren't all that
great. Based on the free Brent Mason mod I might have never bought his book, and certainly wouldn't have ever purchased any of his pedals. Fortunately I was able to do the complete BM mod and was able to hear what I'd been missing.

Are you reading this Brian?

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Post by shooto »

eric_idle wrote:
I've read this thread many times before and saw where Brian gratiously disclosed the parts he changed for Brent's BD-2 but I've read on other forums that he actually changes more than that.
You're absolutely correct. Wouldn't it be nice if these guys would just let us know this up front?

I've done the full mod and the parts he leaves off are significant. They do make a big difference
in the sound of the pedal. The free mod Brian gives away doesn't come close to the full version.
He's doing himself a dissercvice, because it gives one the impression that his mods aren't all that
great. Based on the free Brent Mason mod I might have never bought his book, and certainly wouldn't have ever purchased any of his pedals. Fortunately I was able to do the complete BM mod and was able to hear what I'd been missing.

Are you reading this Brian?

^ so, what is the full mod?

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Post by eric_idle »

^

I know this is a stupid question to ask considering the nature of this forum, but is this actually acceptable to do?

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