New 3PDT True Bypass Grounded Input Wiring Layout by Ulysses

[ulysses]

Hey Guys,

I was looking at the grounded input 3PDT true bypass wiring diagrams on GGG and in my opinion their method is not the best way to do grounded input.

So I designed my own way of doing 3PDT true bypass grounded input wiring.

In the end the answer was so similar to regular 3PDT wiring that you guys have no excuse not to use this method for all your pedals from now on.

You can check it out in my layouts gallery. http://aronnelson.com/gallery/ulysses

Any comments more than welcome 

cheers
ulysses

[darron]

i'll comment. that's pretty much it. i do mine the same except with the ground/led pole in the middle since it's more convenient for pcb mount.

i think though, to make it perfect, you should have a connection between the middle-right and bottom-right pins to remove one unnecessary switch. this would theoretically give better continuity. what's that? it's not worth the trouble.. hmm. yeah.

let this be the new norm! (:

[Dragonfly]

Or you could use this method. I use it, and Barber uses it. Its very "neat and clean" looking, and doesnt have a bunch of overlapping wires. Using this method, the lugs closest to the input and output jacks are the ones used. Plus, this way seems more logical (to me at least) so its easy to remember.

http://aronnelson.com/gallery/The-Mod-Zone-%21/EZ_3PDT_WIRING?full=1

[oldschoolanalog]

Or you could use this method. I use it, and Barber uses it. Its very "neat and clean" looking, and doesnt have a bunch of overlapping wires. Using this method, the lugs closest to the input and output jacks are the ones used. Plus, this way seems more logical (to me at least) so its easy to remember.

http://aronnelson.com/gallery/The-Mod-Zone-%21/EZ_3PDT_WIRING?full=1

+1 on this one. Works great 99% of the time.
Just dont forget the input and output "pulldown" resistors...
I do the "input to ground" thing on high gain circuits. (The other 1%... )

[slacker]

see you just couldn't stay away Dragonfly welcome back amigo.

Ulysses, just interested why do you think there's anything wrong with the ggg method and why is your's better?

[olcircuits]

I got a pedal in December and one last week that are both wired in this manner. These came from two separate customers, so I get the feeling that this diagram was posted elsewhere a while ago. I'm not saying you copied it... just saying that people had this same idea at different times.

[Pushtone]

Just to muddy the waters even more...

Check out this debate about which throw to use for the LED.

http://www.diystompboxes.com/smfforum/index.php?topic=35693.0

[darron]

Or you could use this method. I use it, and Barber uses it. Its very "neat and clean" looking, and doesnt have a bunch of overlapping wires. Using this method, the lugs closest to the input and output jacks are the ones used. Plus, this way seems more logical (to me at least) so its easy to remember.

http://aronnelson.com/gallery/The-Mod-Zone-%21/EZ_3PDT_WIRING?full=1

but it was ulysses's point to have grounded input. are there reasons NOT to ground input? i noticed on te negative ground fuzz face it can start to oscillate with the volume rolled all the way back on humbuckers if you don't us a large enough cap to filter the power supply. that may be a good time to leave the input floating?

[leonhendrix]

Or you could use this method. I use it, and Barber uses it. Its very "neat and clean" looking, and doesnt have a bunch of overlapping wires. Using this method, the lugs closest to the input and output jacks are the ones used. Plus, this way seems more logical (to me at least) so its easy to remember.

http://aronnelson.com/gallery/The-Mod-Zone-%21/EZ_3PDT_WIRING?full=1

I usually wire pedals like this, not so good with wahs though.

[sfr]

I never could get rid of the mild clicking coming out of the trem face when in bypass followed by a huge amount of gain.  Ended up solving the problem by grounding the *output* of the board when the thing was in bypass. 

[ulysses]

hey guys

ill reply to everyone in one foul swoop without quotes.

why is it better than the one barber uses?
my circuit is grounded input, the one dragonfly (good to see you back mate) referenced is not grounded input. which means that the circuit may still generate a signal from a hanging input, and that signal can then 'leak' (through the air so to speak) onto the output of the bypassed signal. this is true of hi gain circuits and circuits with lfo's and other circuits that still generate signals while the input is left hanging. why do circuits still generate a signal from a hanging input? because nothing a absolutly silent unless its attached to ground. a hi gain circuit will take the 'almost nothing' signal from a hanging input and feedback on itself untill that 'almost nothing' is a big high pitched squeal, and that squeal will 'leak through the air' (so to speak) onto your bypassed output. an LFO still pulsates with a pedal in bypass, that can leak onto the bypassed output signal also.

you could take that wiring scheme that dragonfly referenced and modify it to grounded input by adding a single wire, but there are several reasons why mine is still better:
-shorter jump wire between the bypass loop legs.
-doesnt incorporate standard DPDT wiring identically. less familiararity.
-less symmetrical.

why is it better than the one on ggg?
-the wiring on the ggg is not symmetrical in any way.
-the input jack pin is not in line with the output jack pin - the board in pin is not in line with the board out pin.
-the wires cross all over each other in a standard stompbox layout (jacks on left and right, board and led above).
-you cannot easily modify the 3PDT switch between non-grounded and grounded wiring.

so why did i design it like this? the previous diagrams were not logical to me. here is the logic i used to arrive at my wiring circuit.
1. has to be easily modifyable between grounded and non-grounded (a single added wire).
2. has to be symetrical.
3. had to have familirarity with successfull previously designed bypass switching (incorporates common DPDT swiching indentically)
4. board in, board out, led (-) at top of switch so it is easy wired to the board and to the led. output jack on right, input jack on left.

did i steal the design?
no. i sat down and thought about the best way to do 3PDT Grounded Input Bypass Switching and came up with this design on my own. Grounded input has been done by many people before. Is it feasable that they designed it the same way as I did? yes of course it is. If they did come up with the same design then the likely didnt post it online - not in anwhere I could find it.. On the other hand, I posted it for everyone to use. I hope you like it.

the truth is, this circuit is so simple and elegant that I was very surprised to see (when i was designing it) that is was not the common method for 3PDT wiring. I had to do a double take in my head "surely that cant be right, it cant be that simple". it is.

does grounded input have a negative impact on wah pedals?
not that I am aware of. maybe check with RG.

cheers
ulysses

[ulysses]

Just to muddy the waters even more...

Check out this debate about which throw to use for the LED.

http://www.diystompboxes.com/smfforum/index.php?topic=35693.0

analog mike makes an interesting point on not using the middle pole for the led.. interesting read.

cheers
ulysses

[Processaurus]

analog mike makes an interesting point on not using the middle pole for the led.. interesting read.

I was interested but I didn't understand the point, obviously he was having a real problem but it still seems like a mystery.

Your wiring looks good, for high gain stuff I'd move the LED to the middle throw because it keeps the in and outs physically as far apart as possible, and there is a grounded piece of metal in between (the common of the led throw).  This helped out a little with oscilation (output crosstalk getting picked up on the high impedance input) in my extra high gain Big Cheese clone recently, when I tried rearranging the switch.  T'wasn't a night and day dif though.

[darron]

here's my method. it is better:



we are getting pretty finicky here, but i believe this to be perfect... this is much like the other true bypass circuits out there, but combines a bit of the rat style bypass. think of this: just about all true bypasses out there the signal goes in, through a trace/wire, back through the switch and then out. this happens regardless of the effect being toggled on or not. using my method however when the effect is in true bypass the signal only has to travel through ONE switch, like a spst.

you could invert this without any change of quality.

i mentioned this earlier in the thread but it got 'bypassed'... i didn't mean to pun, but... (:

[analogmike]

nice work darron!!!!!!!!!

[audioguy]

Yeah that does look good!

[Skreddy]

I've been doing it this way so long it's just habit. 

[ulysses]

hey analog mike

maybe you could share your current wiring diagram with us

cheers
ulysses

[darron]

thanks mike! it made me feel really good about myself to get such positive feedback from an expect such as yourself. like ulysses, i'm interested in your method also.

we really are being perfectionists here aren't we? but that's what it's about for some people isn't it? can one over use rhetoric? :s

[analogmike]

hey analog mike

maybe you could share your current wiring diagram with us

cheers
ulysses

OK, this is the best I have found, has all the mojo and none of the POPPING:

Take Skreddys, and move the LED- to the left center lug. Move the ground jumper to the top left lug (and disconnect it from bottom left). We have tried them all and this has the LEAST chance of popping due to capacitive leakage (or whatever it is that gets a voltage on the adjacent lugs). But SOMETIMES they will pop like this on the odd switch, then just move the ground jumper back to Skreddy's way and it should work.

good luck!

p.s. I have been using Darron's version (without ground or LED) when we true bypass wahs. They don't seem to need the input grounded when OFF (low gain).