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DIY Stompboxes => Building your own stompbox => Topic started by: soupbone on November 22, 2011, 11:00:01 PM

Title: Buffer?or no buffer?
Post by: soupbone on November 22, 2011, 11:00:01 PM
I was looking at this page; http://www.robtognoni.com/wahwah.htm  He talks about removing the buffer circuit in a crybaby wah pedal.If you've modded it for true-bypass,Why would you need to remove the buffer circuit?
Title: Re: Buffer?or no buffer?
Post by: joegagan on November 22, 2011, 11:14:50 PM
it is a matter of taste. to hear the difference for yourself,  it is easy  to run a jumper to insert your input in at the 68k resistor vs the normal input of a modern 3 trans wah. do this after your other mods since this is how the wah will end up presumably.

i find that once the wah is modded to my liking, i still prefer the unbuffered old school sound better. slightly less harsh in the highs. also, keep in mind that  most customers will have other boss or IBZ type buffered pedals in their chain, so removing one more is a plus ( i am an advocate against indiscriminate 'buffer stacking', why would a person put their tone through a whole bunch of extra trannies/fets when you have choices not to?)

all that said, if you prefer a buffer in the wah, doug hammond put an improved jfet buffer in his modded crybaby.

also, i recently did a germanium mod to a modern style gcb95 3trans. my goal on that one was to radically alter the tone and warm it up with the fewest number of component changes. i left the buffer in, simply adding piggyback caps to the buffer in /out caps to make them larger, since there were larger cap values down the line, i did not want to limit the signal going through the buffer.

Title: Re: Buffer?or no buffer?
Post by: soupbone on November 22, 2011, 11:22:19 PM
Quote from: joegagan on November 22, 2011, 11:14:50 PM
it is a matter of taste. to hear the difference for yourself,  it is easy  to run a jumper to insert your input in at the 68k resistor vs the normal input of a modern 3 trans wah. do this after your other mods since this is how the wah will end up presumably.

i find that once the wah is modded to my liking, i still prefer the unbuffered old school sound better. slightly less harsh in the highs. also, keep in mind that  most customers will have other boss or IBZ type buffered pedals in their chain, so removing one more is a plus ( i am an advocate against indiscriminate 'buffer stacking', why would a person put their tone through a whole bunch of extra trannies/fets when you have choices not to?)

all that said, if you prefer a buffer in the wah, doug hammond put an improved jfet buffer in his modded crybaby.

also, i recently did a germanium mod to a modern style gcb95 3trans. my goal on that one was to radically alter the tone and warm it up with the fewest number of component changes. i left the buffer in, simply adding piggyback caps to the buffer in /out caps to make them larger, since there were larger cap values down the line, i did not want to limit the signal going through the buffer.


Cool!So Joe,If i was to remove the buffer circuit in a newer gcb-95,What components would i need to remove?You're saying too,That removing the buffer gives way to a more "vintage" sound?Thanks Joe!
Title: Re: Buffer?or no buffer?
Post by: joegagan on November 22, 2011, 11:30:30 PM
most ppl just leave the buffer components in place, you have to cut a trace on the board and run the input wire to the 68k resistor, there are many pictorials online that show where the jumpers are cut etc, but it is easy to figure out  too.
Title: Re: Buffer?or no buffer?
Post by: joegagan on November 23, 2011, 12:20:17 AM
doug's version:

(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=42769&g2_serialNumber=1)
Title: Re: Buffer?or no buffer?
Post by: dthurstan on November 25, 2011, 11:55:13 AM
I'm in the process of modding by crybaby at the moment. I've just finished removing all the paint for a new look. I had modded it previously with a DPDT with the buffer in place, I've now completely removed the buffer, I'll probably play with some of the values maybe even put in some BC108's.

I want to reuse the i/p buffer for an o/p buffer.
Title: Re: Buffer?or no buffer?
Post by: joegagan on November 25, 2011, 12:05:58 PM
wow, that's an interesting thought. never thought  of that. don't see why it wouldn't work, other than i don't know too much about what buffers work best for wah output or why. just never messed with em.

because my fuzzes have an input gain pot, this makes them play well with wahs of any type ( something even geoffrey teese noticed way back when).

dthurst, back to your idea, i think a little bit of brainwork and some creative trace cut/jumper action, you should be able to do that nicely. it is cool when you can do a mod using the original board and components.
Title: Re: Buffer?or no buffer?
Post by: joegagan on November 25, 2011, 12:41:49 PM
wah buffer wah buffer wah buffer

( inserted so future generations will find this using the search function since this thread is ostensibly about WAH buffers. didn't need to say it 3X >>just seemed like fun)
Title: Re: Buffer?or no buffer?
Post by: artifus on November 25, 2011, 12:43:52 PM
buffer wah buffer wah buffer wah

(seemed like more fun)
Title: Re: Buffer?or no buffer?
Post by: dthurstan on November 26, 2011, 07:13:52 AM
wah buffer s all round!

Mmm I did think a while back that I could rewire & trace cut the buffer to come at the end of the circuit. However I couldn't be arsed to figure that out, so I removed all the components & I'll stripboard up a small buffer. A bit brute force but I'll see how I get on and get back to you.
Title: Re: Buffer?or no buffer?
Post by: dthurstan on December 01, 2011, 01:21:19 PM
So I breadboarded the buffer section of my crybaby, and compared it to the bypassed signal. I could hear some treble loss with the buffer engaged, however I think this might be down to breadboard and long cables.

I thought more about keeping the buffer in place and like joe said do some trace cutting.
Cut between i/p & 0.01u cap.
Cut between emitter & 68k.
Solder the circuit o/p wire (from the pot) to the 0.01u i/p cap.
Solder a wire from the junction of the emitter and 10k thru a cap to the dpdt switch.

What should the o/p cap of the buffer be? 1uF? A 10k resistor from ground going into a cap is a HPF?

I know it's hard to follow without a picture (stinkfoots tutorial for bypassing a wah has easy to follow pics) but I'm not sure if this is the best solution anyway as you have a cap dangling of the end of a switch. I'm gonna put the buffer on vero.