Using mono io effects with a stereo keyboard rig?

[Krakit]

I bought a too good a deal to pass up looper pedal that has only one in and one out. 

If I send the left channel out from my mixer will that give me a reasonable mono signal or because all my boards are connected to the mixer in stereo will it just be the left channel and not a solution?

 

I'd rather not have to unplug all the right channels just to use this toy only to plug them back in when I'm not using it. 

 

Additionally or alternatively, I would enjoy using this looper pedal with either my Roland Go Keys or Casio CT-S1 but both of these only have phones out. If I were to use a mono instrument cable with 3.5mm to 1/4 inch would that be mono or just half a stereo signal?

[Krakit]

I'm thinking I left out too much.

 

I want to use this looper in the signal path of my in home keyboard rig. I have multiple keyboards set up and using a mixing board(Eurorack and Zoom R16) output to the recently acquired MK1 iLoud speakers. All boards and modules are stereo out to either the Eurorack or directly the the ZoomR16 which is where the Eurorack is sent. 

 

The looper pedal only has a mono input and output (I'm sure it was meant for guitar or bass players exclusively) 

I purchased it knowing this but the price new is under 40usd so I just bought it. 

 

Here's the thing though, I could be just as happy or perhaps even happier if I use this looper exclusively for my battery powered outdoor rig(s). 

The main boards of which are either my Roland Go Keys (3.5mm phones out) or my Casio CT-S1 (same as GO) 

 

So the problem is can I send a stereo signal to this mono effects pedal without ruining the sound?

[stoken6]

5 hours ago, Krakit said:

can I send a stereo signal to this mono effects pedal without ruining the sound?

You can't send a stereo signal to it at all. 

The only option is to send some kind of mono signal:

• Pan centrally in your mixer and take either L or R from there (perhaps your mixer has a mono/subwoofer out?)
• Take one side of the stereo pair into your looper. Easiest way is probably a 3.5mm TRS (stereo) to 2x 6.35mm cable - that way you can check which side (L or R) sounds best.

Cheers, Mike.

[Reezekeys]

Do you have an unused monitor or efx send (and a spare channel for its return) on the mixer?

[Krakit]

Quote

Do you have an unused monitor or efx send (and a spare channel for its return) on the mixer?

 

The Zoom R16 doesn't have any outboard send channels. The effects are internal. The Eurorack does have stereo FX sends but that only accommodates two of my boards and then the Eurorack is routed into a stereo channel of the Zoom. I've been researching this on my own and found this online:

 

http://silentsky.net/wordpress/archives/624

 

(EDIT: The TLDR version is that by introducing a pair of 470 ohm, 1/8 W 1% resisters to a regular stereo/mono summing cable will protect the low impedance circuitry from damage and also prevent unwanted phase cancelation.  I am not an electronics guy TBH. I understand the above premise, but not sure how it will prevent the phase cancellation issues since the left and right channels will still be blended together in the end result. Hopefully someone here can explain the magic to me.) 

 

It's instructions to make a stereo summing cable with passive resisters to prevent phase cancellation and damage to output gear that comes from intentionally shorting the left and right channels together the way most "stereo to mono" adapters do. Does anyone know of a summing cable that comes out of the package with these passive resistors already soldered in? At a reasonable price of course. Otherwise I can prolly workbench this up myself if everyone agrees this will do the trick for me. Thanks for the help so far. 

[Reezekeys]

I'm pretty sure two resistors won't cure any phase issues. I just educated myself a bit (experts feel free to correct me!): resistors can introduce minor phase shifts if they have what's called "parasitic" inductance or capacitance. A perfect resistor won't introduce phase shift. Even if there was some, having two resistors, one on the left lead and one on the right, would most likely be equal or near equal so would have little or no effect on the sound. Having said this, using resistors to tie multiple audio sources together is a well-known way of constructing a passive mixer. Search for that on google and you'll see a few, not very expensive either.

[Krakit]

It's starting to seem that even at the low price this looper is too much of a headache. I think I'll just have to bite the bullet and buy a stereo looper and make life easier on myself. 

[Jose EB5AGV]

6 minutes ago, Krakit said:

It's starting to seem that even at the low price this looper is too much of a headache. I think I'll just have to bite the bullet and buy a stereo looper and make life easier on myself. 

 

FYI, I am using a Boss RC-500 since some weeks ago with my keyboard setup and can recommend it 👍🏻

[Krakit]

5 minutes ago, EB5AGV said:

 

FYI, I am using a Boss RC-500 since some weeks ago with my keyboard setup and can recommend it 👍🏻

I was going to get myself a BOSS RC 505MKII eventually, but this little looper was so cheap I just had to snap it up. I guess I'll just get the 505 sooner rather than later. 

[Baldwin Funster]

I've used passive y cables many times. Many many times. I ve never had it cause a failure because of not having mixing resistors.

 

Now I did add mixing resistors to an ABY box I am using in reverse to combine outputs of some pedals because one side is a passive volume pedal and it was causing some interaction. The mod smoothed it out but didn't eliminate the interaction.

 

If the looper is a performance tool then yeah I could see a mono looper could be a problem.  If it's just to practice to a loop then just go mono before the looper and use a stereo chorus pedal after to make it stereo because who cares its practice.

[Krakit]

1 minute ago, Jr. Deluxe said:

I've used passive y cables many times. Many many times. I ve never had it cause a failure because of not having mixing resistors.

 

Now I did add mixing resistors to an ABY box I am using in reverse to combine outputs of some pedals because one side is a passive volume pedal and it was causing some interaction. The mod smoothed it out but didn't eliminate the interaction.

 

If the looper is a performance tool then yeah I could see a mono looper could be a problem.  If it's just to practice to a loop then just go mono before the looper and use a stereo chorus pedal after to make it stereo because who cares its practice.

I was really hoping to add this looper to my all battery powered micro rig for outdoor fooling around and possible busking.  The above mentioned BOSS 505MKII was a purchase I had planned for my full size studio/stage rig for a later date.

[stoken6]

Surely if all you are looking to use the looper for is 

2 hours ago, Krakit said:

outdoor fooling around and possible busking

then you can tolerate the minor disadvantage of playing mono? It's not like either of the two requires the maximum in sonic fidelity and immersion. It seems a shame to throw away such a bargain because it doesn't do something you don't really need.

 

Cheers, Mike.

[AnotherScott]

Yeah, I know, you shouldn't simply "flip" a Y-cable splitter to make it function as a L/R merger, but really, in any modern gear, I'd be very surprised if it actually ever caused any damage. Fifty years ago was a different story.

 

But also, except for their effects, most sounds in most keyboards are mono anyway. So using just the left (even if both left and right are connected on the keyboard, defeating any internal mono summing) might well be just fine. Auto-panning fx won't work; stereo reverb, chorus, rotary etc. will sound different but not necessarily bad. So maybe the simple answer is to use the looper with just the left channel of the mixer as you want to, to the extent that the sounds are good, and if a sound is crappy when used that way, pick a different sound. ;-) (Or try turning off any stereo effect that might be on the sound.)

[Krakit]

2 hours ago, stoken6 said:

then you can tolerate the minor disadvantage of playing mono? It's not like either of the two requires the maximum in sonic fidelity and immersion. It seems a shame to throw away such a bargain because it doesn't do something you don't really need.

 

Cheers, Mike.

In the thread I express that mono is the goal, it's just not as easy to go mono as you might think