Boneyard mods

[CK1]

Loving my Boneyard so far, though I'm still trying to tweak it a bit.  Using the stock LED clippers, the sound is bright and open.  I'm also noticing that it seems to be just slightly scooped (or at least flatter than I'm used to).  That's fine (and really I love this sound), but it doesn't work quite as well for lead lines. 

So, if I wanted to add some midrange to the boost circuit only (for leads specifically), how would I do that?  Would I have to change some cap and resistor values in that part of the circuit to cut bass and treble, or is there another way to increase midrange?  Thanks in advance for any info.

[TheCobbenator]

Agreed. I would like to add bass and or mids to mine to get it more in the JTM range -- sounding more like the box of rock and less trebly.

[shawnee]

C4 is a 330p cap and is there to stabilize that stage of the opamp and cut some highs. Maybe you could raise it. It won't add mids but if you cut the extreme highs, you would be able to turn the tone knob up more and that will add some mids. I haven't tried it so I am just taking a stab at it. Experimentation is where it's at!

[CK1]

Thanks for the suggestion, shawnee.  Might try that. 

Anyone else have a decent suggestion?

[shawnee]

Here is an answer that I got from a forum brother who knows his stuff:

You could put a cap in parallel with R8. I'd start with about 100nF. Then put a cap to ground from the junction of R8 and C8. Maybe 10nF or 22nF to start. You will probably have to experiment with different values to get the desired response.

The more complex way would be to add another opamp stage and implement Craig Anderton's mid-range booster circuit. It can be found in this thread over at DIYStompboxes:

http://www.diystompboxes.com/smfforum/index.php?topic=81687.0

I'd put it at the output to the third stage, before the volume pot (you could put it on a little perfboard). Note that the bottom of that switch should go to Vref, not ground as shown!

[CK1]

Sweet!  I was genuinely hunting a good option on my own, but hadn't found much.  Thanks for digging, man.  A PM will probably be on your way once I can take a crack at this.

[shawnee]

I am obsessed with the Boneyard! I have gotten some great answers, suggestions, and tweaks on this forum. There are some great guys here who really know their stuff and are willing to help. I wish I could figure this stuff out on my own but it will take time. Please post and let me/us know how it worked and what values you settled on.

[matticus]

Hey, everyone. This is my first post here!

I bought a Boneyard from a guy awhile ago and have LOVED using it since then. What I haven't had time to do, though, is to think through some mods. I'm still at the paint-by-numbers stage of circuits but love learning more and more.

What I'm interested in is sort of two-fold:
1) Whether it's possible to mod the pedal to choose Plexi or AC (since they have similarities); and
2) What to do with the boost section that I never use (midboost?; rehouse?).

[shawnee]

The AC and the Plexi are the same pcb but there are some other slight changes besides just the clipping. It isn't practical to do both in one pedal if you want them to exact. You may be able to just add a switched clipping section and split the difference between the other components but I haven't done it to give you any feedback on results.

You can just leave the boost off all together. Just don't even put the wires on the board if you don't want a boost. You can jumper the pot connects on the pcb but it still works as normal if you don't.

[slimtriggers]

Is there a list of substitutions somewhere to turn this into an AC?

[matticus]

The AC and the Plexi are the same pcb but there are some other slight changes besides just the clipping. It isn't practical to do both in one pedal if you want them to exact. You may be able to just add a switched clipping section and split the difference between the other components but I haven't done it to give you any feedback on results.

You can just leave the boost off all together. Just don't even put the wires on the board if you don't want a boost. You can jumper the pot connects on the pcb but it still works as normal if you don't.

Yeah, I wondered whether there were just too many changes to make it worthwhile...

I suppose I could try including one stage of the AC instead of the boost?

Slimtriggers, I haven't made a list yet but it could be made. I've got both schematics around here somewhere...

[slimtriggers]

Slimtriggers, I haven't made a list yet but it could be made. I've got both schematics around here somewhere...

That'd be great!  Thanks

[shawnee]

You can pull it all up on freestompboxes.org. Just search for plexituna and acetone. They have a great layout that includes an +/-18v supply omboard from a single TC1044 or LT1054.

[slimtriggers]

You can pull it all up on freestompboxes.org. Just search for plexituna and acetone. They have a great layout that includes an +/-18v supply omboard from a single TC1044 or LT1054.

Found it!  Thanks!

[shawnee]

Please post and tell us what you think if you build either one.