Can I Mix and Match Schematics? (Build Goal: The Worst Pedal... In The World)

Started by BeefTech, April 20, 2015, 06:37:32 PM

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BeefTech

Hi all,

Bit of a beginner here (okay I've never done anything like this at all) and in my quest to make things as difficult as possible for myself, I'm trying my hand at building my first pedal without doing any of the beginner projects.

I'd like to do something simple like the Total Sonic Annihilation: http://www.diystompboxes.com/smfforum/index.php?topic=63293.0

but rather than running it as an effects loop, I'd also like another module wired inline in the same housing. In this case, I've got an old Boss MT-2 Metal Zone laying around: http://www.hobby-hour.com/electronics/s/boss-mt2-metal-zone.php

Is there a simple way to combine these two in the same housing? Like, could I just run the "output" wires of the TSA into the "input" wires of the MT-2, then cram both into the same stompbox housing with the associated switches and knobs? Or is it more complex than that?

BeefTech

Just to clarify, I would want the functionality of both pedals in the same box and the ability to turn them both on and off independently (though "at the same time" is a great option too). Basically I just don't want to have to run a patch cable between the two boxes.

That being the case, could I just run the output of one to the input of another? Or would I need to wire the input/output of the MT-2 into the send/return of the feedback looper?

I also realize that this would probably take either two batteries or two 9v DC adaptors, though if there's another way to do this I wouldn't be opposed.

My ultimate goal is to make a couple of different boxes that basically function as both feedback loops AND add an additional amount of ungodly noise, via reverbs, choruses, flangers, etc - whatever pedals I can find.

mth5044

Yep, you can go from the output of the first circuit into the second. A patch cable is the same thing as two wires, one with signal and one with ground. Since your circuits are in the same enclosure, they will already be sharing the ground, so you just need to worry about the signal.

You can use one battery or power jack. Think about a daisy chained supply. You are running a bunch of pedals in a row off the same supply. So, again, just replace the outside cord with an inside wire. In this case wire four power wires to each effect, +9V and ground. Except the first circuit you posted doesn't need voltage unless you are using an LED!

It's helpful to draw it out. Post a picture of your wiring sketch idea for some feedback!

BeefTech

Oh man, I don't even know how I would draw this. I can't even find the output jack on the MT-2's  schematic. :icon_lol:

If someone wanted to draw that, that'd be cool.

So output of first circuit goes into second (hot to hot, ground to ground), and then run them off of a common "hot" +9v and a common ground?

I will be using an LED for both. Preferably blue, but I don't know how I'd calculate the resistor values.

mth5044

Nah, I don't mean a schematic. More of a wiring diagram.

There are current limiting resistor calculators online, but if it's a clear one, I like to go fairly high. 10kish area as I hate being blinded. 4k7 is a good one if you like them bright.

BeefTech

Alright, I will rig something up using the two above schematics and some crudely drawn lines when I have time.

I want the LED to be VERY bright, I am building this for a friend as an experiment and we are using the clear stompbox bottoms from smallbear, so the light will just be illuminating the inside of the stompbox.

I'm also making one for myself, so, I guess I'll need to find two 4k7 resistors.

antonis

Quote from: BeefTech on April 20, 2015, 10:08:55 PM
Just to clarify, I would want the functionality of both pedals in the same box and the ability to turn them both on and off independently (though "at the same time" is a great option too).
Hmmm...

If you wire them in series you must have a bypass switch for each one so you'll be able to select between 4 options: First ON - Second OFF, First OFF - Second ON, Both ON and Both OFF.. (OFF meaning Bypassed..)

If with the "at the same time" option you mean active pedals in parallel (simultaneously but independently) you have to add a switch between First pedal OUT and Second pedal IN to break off connection between the pedals, connect signal to IN 2 and connect OUT 1 to OUT also..
You have to mix the signals either by a single pot (middle lug --> OUT) or by a pot with two equal resistors for balance and avoiding "inter-loading" (middle lug --> GND)...


P.S.
I'm waiting for duck_arse's comment about "interloading... :icon_biggrin:
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

duck_arse

" I will say no more "

BeefTech

Ha!

I've been playing around with it and I'm thinking there's really no reason I'd ever want to just do one or the other since the goal of this pedal is just horrific, raucous noise. So could I just wire them to the same on/off switch and turn them both off and on at the same time?

The schematic I have shows a 3PDT switch, is there a way to wire BOTH the feedback looper and the MT-2 to it?

antonis

Quote from: BeefTech on April 21, 2015, 03:05:33 PM
So could I just wire them to the same on/off switch and turn them both off and on at the same time?
I'm not sure about what you mean by this...

If you refer to power supply, yes you can (as long as the PSU is total current efficient..)

If you want to turn on/off theirs outputs at the same time maybe you'll need something like the following circuit:



"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

mth5044

Are you putting the metal zone in the loop of the feedback circuit, or are you putting them completely in series?

Using the Metal Zone is going to cause you problems. It uses it's own bypassing circuit. I believe boss pedals use a momentary switch, but it's been a while. Hooking up both on one switch is not difficult. What Antonis posted is if you are running the circuits in parallel, but I believe you are using them in series? In which case, you won't need that.

IF you can bypass the metal zone's on board switching and hijack it to be "always on" (do some forum and Google searching, it can be done!), it will be a simple case of using the input of the first circut and the output of the last. You will link the two circuits together via output of the first and input of the second. Now you have one larger circuit with one input (of the first circuit in series) and one output (of the last circuit in series) and can wire it like a normal bypass. Check out tone pad wiring diagram for how to wire, I suggest the fifth diagram.

For simplicity, would keep the bypass switch for the feedback circuit as a toggle. That way you won't have to figure out how to incorporate that into your new bypass scheme and you can use it to use just the metal zone if you need to.