Advice About Running Simultaneous Inputs (ABY In)

**Bryan R. Tyler** · #1 10-10-2008, 07:18 AM

I'd like to run my Handsonic percussion thingamabob in through my setup at the same time as my bass. Brian at Loop-Master has advised against using a passive ABY for using two inputs in the past as there can be grounding issues. I never actually tried to run two instruments in when I owned my Radial Switchbone either, so I don't know if a buffered ABY would work. The ones I've found don't mention if they were designed to take two simultaneous inputs. Does anyone have any experience with an ABY that would work well for this application? A mini mixer would probably work, but I'd prefer to have the footswitchable option of turning either of the signals off that an ABY would give.

Loop-Master · #2 10-10-2008, 07:43 AM

Well see, if you turn off your bass while this is going on, you'll ground out your signal as this is how a potentiometer is wired on an electric instrument.

And since you're sharing an input with another device, you'll turn it off too since the ground is shared as well as signal.

If you connect another device and don't plan on turning down the volume, it'll work with a passive A/B.

I guess I could wire up a custom box to connect and disconnect the other device completely so that the above won't be an issue. Holler at me via email if you want.

**Bryan R. Tyler** · #3 10-10-2008, 07:47 AM

I'm not positive I understand your post- are you saying that if I run both of my instruments at full volume simultaneously, there shouldn't be a problem using a passive ABY? The other instrument is basically a drum machine, so it and the bass would need to be providing a signal at the same time for certain periods.

Loop-Master · #4 10-10-2008, 07:52 AM

Quote:

are you saying that if I run both of my instruments at full volume simultaneously, there shouldn't be a problem using a passive ABY?

Right. And if you turn one's volume down, you'll be turning the other down at the same time since they share the signal.

**Bryan R. Tyler** · #5 10-10-2008, 07:59 AM

That's weird. I still have a custom ABY with separate loops per output you made me somewhere around here- I'll dig it out and give that a whirl.

scotch · #6 10-10-2008, 08:15 AM

If you're planning to use both simultaneously, I think an active mixer is in order. I see people do this a lot with compact behringer mixers.

If you only need to switch back and forth from one instrument to the other, Loop-Masters fully disconnecting a/b box idea would work. You could get a "pop" through the amp though, I would imagine....

TaySte_2000 · #7 10-10-2008, 08:19 AM

Boss LS-2 will work

scotch · #8 10-10-2008, 08:20 AM

Quote:

Originally Posted by TaySte_2000

Boss LS-2 will work

I always forget about the LS-2, that will totally work....

**Bryan R. Tyler** · #9 10-10-2008, 08:22 AM

I forgot how the toggle works on the LS-2- would it go from ABY to B to A back to ABY with consecutive presses?

TaySte_2000 · #10 10-10-2008, 08:26 AM

Quote:

Originally Posted by Bryan R. Tyler

I forgot how the toggle works on the LS-2- would it go from ABY to B to A back to ABY with consecutive presses?

What you are more likely to do is run the bass into the input and the other instrument into a or b return and just toggle a or b on I think at least anyway.

The radial ABY one might be better they use isolated transformers in theirs and they have ground lifts etc

**Bryan R. Tyler** · #11 10-10-2008, 08:35 AM

Quote:

Originally Posted by TaySte_2000

What you are more likely to do is run the bass into the input and the other instrument into a or b return and just toggle a or b on I think at least anyway.

The radial ABY one might be better they use isolated transformers in theirs and they have ground lifts etc

I don't need just A on or B on though- I need both on (the Y function) for certain things. Can the LS-2 do that?

TaySte_2000 · #12 10-10-2008, 08:50 AM

Quote:

Originally Posted by Bryan R. Tyler

I don't need just A on or B on though- I need both on (the Y function) for certain things. Can the LS-2 do that?

Yeah but I think you have to plug each instrument into the return of A and B and I think for it to work you might need to put something like a George L jack with no cable connected into the input.

I'm thinking of getting one of these though

http://thesquarewaveparade.com/bleakmixer2.html

Not saying it's better from the LS-2 far from it, I just don't see any issues if I hook up bass, keys and stylophone to my pedalboard at the same time.

**Bryan R. Tyler** · #13 10-10-2008, 09:02 AM

The one issue I have with using a mixer and having all inputs on at all times is that any ambient noise from the instruments you're not using will come through. My Handsonic, for example, has a function where you can trigger a sound simply by waving your hand over a sensor. My headstock would be triggering that sensor quite a bit if the Handsonic was always audible

That's why an ABY would be much more convenient if using just two instruments.