# Teach me buffered bypass :-/



## jcrews (Apr 16, 2021)

I built the informant.(and I really, REALLY dig it)   Like all my other builds I built it True Bypass.  I don't have a buffer in this board I'm currently running on.  I usually have a klon somewhere in the chain, but i replaced it with a SHO.  

I played my buddies real deal DRV the other day and the switch in it feels AMAZING.  super soft.  silent.  Butter.  (fwiw the sounds it makes are nearly indistinguishable, it MIGHT have a slightly lower noise floor.  MAYBE.

He said he was happy with the buffer in the pedal and could hear a diff.  

I'd like to change mine up but I have some questions as I'm a total noob to "buffered bypass"  (I am not unfamiliar with buffers though)
I see this board has a diagram from BP and a slightly diff switch config.  I'm gonna assume this works like a boss pedal on and off wise, and the buffered part means I'm actually adding a buffer to my signal when the effect is off if I wire it this way?  Right?

If that's the case I'd love a suggestion on the best switch to buy.  I don't care what it cost, I would love to have my first soft touch pedal.  Down for a premium option or whatever i can get my hands on that feels like whatever they used.

bonus question.  Are the soft touch switches in all the newer wampler pedals an indicaiton that they are "buffered bypass" as well?  Just curious.  Def learning as I go if it's anything but TB


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## giovanni (Apr 16, 2021)

You are correct. Buffered bypass means that the signal is buffered when the pedal is off. I don’t know which soft switch to recommend.


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## phi1 (Apr 16, 2021)

Click and soft touch switches can both be configured as true bypass or buffered. Many boutique brands use relay controlled true bypass (Wampler and eqd included). There’s a small relay bypass pcb on this site that allows you to do exactly that, have soft touch true bypass. It sits right on top of the momentary footswitch so it fits easy in almost any build. 

How it works: the momentary footswitch is hooked up to a microcontroller, then the microcontroller switches a relay. If you study the diagrams, you can see electrically it works exactly the same as the normal 3PDT true bypass wiring.  You could maybe use this same pcb and achieve the buffered bypass function of the informant by studying the diagrams and figuring out what wire would go where.

boss pedals and have a soft momentary switch but don’t use a microcontroller or relay. They use a method of flip-flopping get transistors to electrically divert the signal. This works fine for buffered bypass, but not true.


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## jcrews (Apr 17, 2021)

Thanks   So as I understand it, I can use the same 3pdt switch i have now and an extra wire from the board to use the built in buffer when the effect is off. (built in feature of the informant).  I'll still have the same tactile feel to the switch obviously, but I'll be able to utilize the buffer.
I can also use an additional PCB and a momentary switch to add soft touch switching to any other pedal pcb effect while retaining true bypass switching.  (that's super cool to know.  I have a TON of momentary switches with two leads left over from boss rehouse work).
I'm assuming I can also use one of these relay switching boards to have a soft momentary switch, AND still access the buffer in the informant circuit.

I took a look at what was available (or waitlisted) as far as relay bypass PCB's go.... there are 3-4 options.  Which one do I need for the following:

1.) replace a standard hardwired 3pdt true bypass wired effect with a moentary switch retaining true bypass.
2.) replace the standard 3pdt switch in the informant with a momentary switch retaining buffered bypass.

(simple vs. intelligent relay bypass/latching vs non)


I'm sorry for the absolute beginner questions.  I'm not circuit dumb, but the soft touch thing and relay's are all new to me.

thanks for your patience and expertise.

Just want to figure out how to upgrade my footswitch to something soft-touch AND access the buffer.


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## manfesto (Apr 17, 2021)

All of simple and intelligent relay boards, latching and non, do the same fundamental thing - press an SPDT switch, effect turns on, press it again, effect turns off.

The intelligent boards have additional functionality (like momentary activation, channel switching stuff, etc), but if all you want is a soft-touch switch to turn the effect on or off, either of the simple boards will work just fine (the non-latching has a cheaper BoM, the latching draws less power, but functionally they’re identical).

I’m sure someone will correct me if I’m wrong, but I think it looks like if you wanted to use a relay board and use the buffered bypass, you would

1. connect your 1/4” input jack to the “IN” pad on the Informant board
2. connect the “BP” pad on the Informant board to the “JACK IN” pad on the bypass board
3. connect these - “GND”, “SW”, “OUT”, and “JACK OUT” - as normal.

(for true bypass, you’d just connect the four pads from the Informant board to the bypass board as normal)


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## jcrews (Apr 17, 2021)

thanks for the rundown.  There's a lot of room in these 125b's since im not using battery snaps.  

Anybody who rolls soft touch have switch suggestions?  I'm assuming since i need SPDT (6 lugs) all the soft touch stuff i have with two lugs is out.

Whats the best switch on the market for converting this and a few of my other TB pedalpcb builds?


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## phi1 (Apr 17, 2021)

Yep I think manifesto nailed it.

you want SPST momentary switch. Only 2 lugs. Simplest type of switch there is, lugs are normally unconnected, then they connect when you press the switch.

It’ll look like this.


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## jcrews (Apr 17, 2021)

solid. i got confused.  I have a bunch of those.  Went through a phase where i was rehousing my buddies dd-20's like a sadist. :-/

not seeing a BOM on any of these.  Those hiding somewhere?


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## phi1 (Apr 17, 2021)

I'm always a fan of teaching theory too.  Here's an awesome article from madbean where you can really see what's happening in true bypass 3PDT (clicky) switches.  It's 3 separate switches in there, 2 controlling signal flow and 1 controlling the LED.  (The number before the "P" indicates how many switches (P stands for pole which is the center lug of the a switch)).  Madbean's final diagram looks slightly different that PedalPCBs true bypass wiring, but in works in the same way).



			https://www.madbeanpedals.com/tutorials/downloads/MBP_FootswitchWiring.pdf
		


Then checkout the schematic for the intelligent relay true bypass board, and see how it's doing the same thing.  The difference is, the 2 switches controlling signal flow are the relay (it's a DPDT relay).  The LED is controlled by one of the other microcontroller outputs. 

Here's what Manfesto did to come up with the instructions for relay bypass board with buffered bypass:  Study the physical connections of the buffered bypass diagram (Informant build docs), and map those to the relay switch connections in the schematic (Relay bypass pcb build docs)


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## jcrews (Apr 17, 2021)

love these madbean writeups.  Thanks for sending along.  Makes perfect sense.  Excited to mess with relayed switching for the first time.  I have a big loop switcher I'd love to overhaul with the softies.

I just ordered a bunch of the relay boards.  Not seeing any build docs anywhere to build my parts orders with.... Those floating around anywhere?


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## manfesto (Apr 17, 2021)

jcrews said:


> love these madbean writeups.  Thanks for sending along.  Makes perfect sense.  Excited to mess with relayed switching for the first time.  I have a big loop switcher I'd love to overhaul with the softies.
> 
> I just ordered a bunch of the relay boards.  Not seeing any build docs anywhere to build my parts orders with.... Those floating around anywhere?


I can’t remember if this is the BoM for the latching or non-latching, but



			https://forum.pedalpcb.com/threads/simplest-relay-bypass-possible-no-microcontroller.4478/page-3#post-45674
		


EDIT looked it up, the A-4.5W-K is a non-latching relay, so it’s the BoM for the non-latching simple bypass board, and I think you can get the relays cheapest on Tayda


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## jcrews (Apr 22, 2021)

manfesto said:


> All of simple and intelligent relay boards, latching and non, do the same fundamental thing - press an SPDT switch, effect turns on, press it again, effect turns off.
> 
> The intelligent boards have additional functionality (like momentary activation, channel switching stuff, etc), but if all you want is a soft-touch switch to turn the effect on or off, either of the simple boards will work just fine (the non-latching has a cheaper BoM, the latching draws less power, but functionally they’re identical).
> 
> ...


True wizardry.  Got the latching relays built and ready for three pedals.  your layout modification is perfect.  While i was waiting, i did the following to "hear" the buffer in my chain (informant overdrive)  Any chance i can modify that to maintain my switch?  I understand the premise of what the switch is doing, but I'm lost with the extra wires I having ditched the 3Pdt for a soft touch two terminal switch for my latching relay.


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## jcrews (May 1, 2021)

UPDATES:

I finally threw in the towel on trying to figure out how to incorporate the "switchable" buffer on my relay switching versions....
Couldn't decide on the buffer or not so..... I just did them both.  Bigger dude has the "stock" soft touch switch and buffered bypass
The little fella has soft touch true bypass.

Both of them have the clipping mod.  Can't say enough good things about the clipping.  I LOVE the LED's vs the diodes and the NONE setting in the middle sounds great as a clean boost with the DRV down, and also great with just op amp clipping as you go up the DRV knob range.  Really great sound.  the LED mode is louder and the NONE mode is WAY louder.

I feel like they really nailed this circuit and these tiny clipping mods really worked well to give it a little more dynamic range.  It will do more for me now, so I'll use it more.

Anyhow thanks to the brain trust here.  These were my very first ever relay'd bypass builds with the soft touch.  They won't be my last.  It's a pain and extra work but it really makes a pedal feel premium.  I won't use it always but I am already eyeing a new loop switcher built around these.

Thanks again for all the patient explaining to a noob.


Y'all are the best.


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