Author Topic: Let's talk about relay bypassing  (Read 281 times)

Tuxedo3

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Let's talk about relay bypassing
« on: September 07, 2017, 06:45:07 AM »
Hey guys, I see lots of pedal companies using soft touch switches and relays to engage their pedals. I am in huge favor of this, I think it's innovating past the 3pdt switch for stompboxes. So here's my question, how many of you use relays and what's the best way to do this? I'd love to incorporate this into my builds but never have done it before. Thanks all.

zombie_rock123

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Re: Let's talk about relay bypassing
« Reply #1 on: September 07, 2017, 07:08:10 AM »
There's a transistor based method that I've used and works quite well, I'd up the debounce cap though - http://tagboardeffects.blogspot.co.uk/2014/06/soft-latch-relay-bypass-daughterboard.html
There's PCBs over at 1776 and TH Customs *Probably others too*.
And theres an OSH Park share of the RG Keen (I think!) method using a CMOS chip and a couple of transistors, this was mentioned in a build thread recently and looks awesome.

As far as methods I think it's either CMOS logic, transistor logic or microcontroller. I believe the man himself Bean has a board coming out from one of the Sneak Preview threads that will be microcontroller based.

Best way is probably microcontroller but that involves either having the PICKit to flash the code to it and writing the code - there's a brilliant relay bypass article written by a Bean user over here that is comprehensive and an awesome read: http://www.coda-effects.com/2016/04/relay-bypass-conception-and-relay.html and you could probably get good at coding and have fun with other options - bypass for pressing but hold does something different like engages feedback or swells or something - but if you're like me coding is a mystery. Transistor and CMOS based may be simpler but can be a bit bulkier depending on the layout.

dan.schumaker

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Re: Let's talk about relay bypassing
« Reply #2 on: September 07, 2017, 07:36:33 AM »
I have used the RG Keen CD4069 method in a few builds, and I have enjoyed working with it.  It is fairly simple, uses a relatively cheap relay and works.  I am not informed enough to know what the benefits of a PIC vs CMOS switching is though.  If you want to do some more complex switching (ie. momentary modes in switching), microcontroller is the way to go.  But for simple on/off, i'm not sure what is "better".  I have also used the 1776 effects microcontroller relay with good results.

I have been drawing up a few boards with the CMOS switching integrated into the effect.

WormBoy

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Re: Let's talk about relay bypassing
« Reply #3 on: September 07, 2017, 07:52:56 AM »
Generally, I don't use them: too complex, too bulky, too much current draw, dislike muting (or pops, which relays are prone to). Did build a programmable FX switcher once (according to the GeoFex article) for a friend, which is pretty nice, and would not be possible without relays. No pops as the circuit includes a nifty way to slow down the voltage change across the relay coil. The traditional 3PDTs have worked well for me, and some of my builds have seen a lot of tough action on the road  8). YMMV.

warriorpoet

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Re: Let's talk about relay bypassing
« Reply #4 on: September 07, 2017, 07:55:09 AM »
Generally, I don't use them: too complex, too bulky, too much current draw, dislike muting (or pops, which relays are prone to). Did build a programmable FX switcher once (according to the GeoFex article) for a friend, which is pretty nice, and would not be possible without relays. No pops as the circuit includes a nifty way to slow down the voltage change across the relay coil. The traditional 3PDTs have worked well for me, and some of my builds have seen a lot of tough action on the road  8). YMMV.

All of these are reasons I switched over to DeMont soft-touch 3PDTs
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bsoncini

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Re: Let's talk about relay bypassing
« Reply #5 on: September 09, 2017, 04:41:02 PM »
Call me old fashioned but I like the normal 3pdt with a click when you step on it. There is definitely some pedals that benefit from other switching methods but it's a bit of a bummer to spend almost as much money on the switching as you do the actual circuit.

m-Kresol

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Re: Let's talk about relay bypassing
« Reply #6 on: September 10, 2017, 02:51:07 AM »
Call me old fashioned but I like the normal 3pdt with a click when you step on it. There is definitely some pedals that benefit from other switching methods but it's a bit of a bummer to spend almost as much money on the switching as you do the actual circuit.

I would recommend optical bypass then. It's only a bit more expensive than a 3PDT bypass, has the clicking you like, but softer. Also less likely to fail and to pop
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Tuxedo3

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Re: Let's talk about relay bypassing
« Reply #7 on: September 10, 2017, 10:28:56 AM »
Thanks for all the replies everyone, some really helpful stuff in here.

Best way is probably microcontroller but that involves either having the PICKit to flash the code to it and writing the code - there's a brilliant relay bypass article written by a Bean user over here that is comprehensive and an awesome read: http://www.coda-effects.com/2016/04/relay-bypass-conception-and-relay.html and you could probably get good at coding and have fun with other options - bypass for pressing but hold does something different like engages feedback or swells or something - but if you're like me coding is a mystery. Transistor and CMOS based may be simpler but can be a bit bulkier depending on the layout.

As a lover of Arduinos and Raspberry pi, this article is amazing. I think I'll try this one.

JC103

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Re: Let's talk about relay bypassing
« Reply #8 on: September 10, 2017, 11:28:47 AM »
Generally, I don't use them: too complex, too bulky, too much current draw, dislike muting (or pops, which relays are prone to). Did build a programmable FX switcher once (according to the GeoFex article) for a friend, which is pretty nice, and would not be possible without relays. No pops as the circuit includes a nifty way to slow down the voltage change across the relay coil. The traditional 3PDTs have worked well for me, and some of my builds have seen a lot of tough action on the road  8). YMMV.

Where do you buy them and how much?

All of these are reasons I switched over to DeMont soft-touch 3PDTs