Crybaby Bypass

[Lord-of-the-strings]

Well... my crybaby sucks my tone when it's in the off state, so how do I go about making it a true bypass? Any diagrams would be appreciated

[ansil]

ok heres the jist of it. true bypass is nothing more than a straight input to output with nothing in between. so you would disconnect the wire coming from the input jack [the hot wire not the ground] and connect it to one side of the swich. do the same for the output in one posistion it should connect to the orgiinal point it camef rom. and in the other you should connect them together.

i will draw it for you.

[lovekraft]

Just me, but you might want to hang a pull down resistor on that input (1megohm or so to ground) so the input cap isn't floating when it's bypassed - the switching pop might not be a problem, but with a little gain downstream, it'd still be potentially annoying.

[ansil]

true true but i thought i would let him figure something out for himself.

ed

[Paul Marossy]

Here's what I did to my wah: http://www.diyguitarist.com/DIYStompboxes/WahTrueBypass.htm

[andaliteuk]

ther should be a easy way to eliminate the switching pop, if i remember right the pop is caused by the ground being disconnected and reconnected, am i right?? you can get guitar cables that have a device in the jack so they dont pop when you unplug you guitar, im gonna look at how they work so i shud b able 2 work something out for you.

p.s. try going on google and searching for bypass unit diagrams- i have seen popless bypass units, i just cant remember where

[andaliteuk]

jus remembered i think its sumthing to do with making sure ground makes contact before the signal and the signal breaks before ground

what you need to do is work out a way to switch without disconnecting ground, ile c what i can come up with

http://www.loop-master.com/catalog/product...&products_id=68 try this maybe??

Edited May 4, 2006 by andaliteuk

[andaliteuk]

http://www.stinkfoot.se/andreas/diy/articles/bypass.htm this explains a bit

http://www.singlecoil.com/tb-strip/tbstrip.html look at the bit titled "The True-Bypass Strip FAQ" it has lots of diagrams u can modify to suit the pedal

Edited May 4, 2006 by andaliteuk

[Paul Marossy]

I think the pop could be eliminated by simply putting a 1M pulldown resistor on the input - if we are talking about a wah that does not have an input buffer. A pulldown resistor is simply a resistor to ground before the input cap (if one is present) that prevents a sudden DC voltage from occuring when switching, and yet has minimal impact on the input impedance of the circuit.

[tasty]

Generally the pulldown resistor is the way to go. I modded my cry baby with the buffer removal, addition of a LED on the left (to indicate status) and internal trim pots that change the output gain and the Q factor of the wah. I really love my cry baby now that its all modded out. I would reccomend this mod to anyone! I can tweak the wah till im happy with the sound, I know if its on or not and its true bypass to boot! All parts are availible at any radio shack (with the exception of the 3dpdt switch). Just break out the soldering iron and go for it!

[Paul Marossy]

addition of a LED on the left (to indicate status)

Have you had any problems with popping noises when switching after adding an LED? I have thought about adding an LED to some of my wah pedals, but I have concerns about possible popping noises when switching. I have had a few projects where even though you have a pulldown resistor, it'll still pop when switching...

EDIT: This is a good read - http://www.muzique.com/lab/led.htm

Edited May 5, 2006 by Paul Marossy