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Combining two signals into one output.

So, I'm looking at a direct rig situation where I have two bass pre/DI pedals that are setup to have two very different jobs and i want to be able to switch by an AB switch between them. That's the easy part for me: AB switch.

The output is my question. I'll never want both signals on and flowing through at the same time. It will be one or the other. I just want to have both feeding into a "combiner" so that I only need a single cable (1/4" or XLR) to go to the console. Any ideas on such a thing? Almost like a SUPER simple mixer. ....but wont need to adjust levels or EQ. ....or mix. Lol.

Thanks!
 
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The output is my question. I'll never want both signals on and flowing through at the same time. It will be one or the other. I just want to have both feeding into a "combiner" so that I only need a single cable (1/4" or XLR) to go to the console. Any ideas on such a thing? Almost like a SUPER simple mixer. ....but wont need to adjust levels or EQ. ....or mix. Lol.

What you need is a summing circuit. It can be as simple as 2 resistors anywhere in the 1k - 10k range. Rane have a great article [Invalid or Expired Link Removed] & I also found this with a quick search. Good luck!
 
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Very cool! I won't need all bells and whistles though. I mean that I won't need to manually toggle between one signal or the other. The signal will just simply becoming from one or the other.

One Control White Loop
Definitely very close. I am hoping for one that also has a XLR return and single output and not just the 1/4". I know this is super specific and may end up just having it built.

What you need is a summing circuit. It can be as simple as 2 resistors anywhere in the 1k - 10k range. Rane have a great article [Invalid or Expired Link Removed] & I also found this with a quick search. Good luck!
Thanks! ...but would I need a summing amp if the signal is only going to come from Source A or Source B but never Source A and Source B? Could maybe a glorified Y cable work here for that?
 
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Seems like the Boss LS-2 would be the perfect solution for your needs, basically a small pedal form mixer with two build in effects loops, each with a dedicated volume control, as well as it has a control switching knob for setting it to different functionality and switching modes.

You would also be able to just use the effects loops Return input jack sockets if you don't need your preamps to be in the separate parallel effects loops that the pedal offers.
 
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Thanks! ...but would I need a summing amp if the signal is only going to come from Source A or Source B but never Source A and Source B? Could maybe a glorified Y cable work here for that?

No, you should never use a Y cable to merge/sum signals, only for splitting. The Rane article I linked explains why.
 
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No, you should never use a Y cable to merge/sum signals, only for splitting. The Rane article I linked explains why.
That's just it. I am not merging two signals. It is only one. It will be coming down side A or side B. Not side A and B. Side A would have Bass A connected to it. Side B would have Bass B connected to it. I can only play one at a time and the signal to B will be muted when playing A. So... there's virtually no chance of there being two signals coming down the wye at the same time. I was talking with a buddy of mine last night, not sure why I didn't think to ask him to begin with (always nice to have a lead amp designer for a well known amp manufacturer as a childhood friend!) but he was saying the only concern he'd have is impedance but given where this would occur in the signal path, it should be absolutely fine. ...just don't run a signal down both sides of the wye at the same time. For that, as you pointed out, I would need a summing amp.
 
That's just it. I am not merging two signals. It is only one. It will be coming down side A or side B. Not side A and B. Side A would have Bass A connected to it. Side B would have Bass B connected to it. I can only play one at a time and the signal to B will be muted when playing A. So... there's virtually no chance of there being two signals coming down the wye at the same time. I was talking with a buddy of mine last night, not sure why I didn't think to ask him to begin with (always nice to have a lead amp designer for a well known amp manufacturer as a childhood friend!) but he was saying the only concern he'd have is impedance but given where this would occur in the signal path, it should be absolutely fine. ...just don't run a signal down both sides of the wye at the same time. For that, as you pointed out, I would need a summing amp.


All you need is a simple A/B-Y box.

You can probably get one new for about $15 (does RadioShack still exist).

The ART CoolSwitch is just a branded version of a pretty common, cheap A/B-Y box, and even then, it's dirt cheap.

Bass#1 - preamp#1 - input A

Bass#2 - preamp#2 - input B

Either common output - amp / DI

(A/B-Y box sockets are bi-directional, so ignore "input" / "output" labels).
 
Further to my last post, I just did a quick search, and the world is your lobster :

Mooer make a cheap micro pedal

Electro Harmonix make the "Switch Blade", a cheap nano pedal, and a cheap regular pedal (as well as a more expensive active version).

Fender make a really cheap pedal.

Other than the more expensive Electro Harmonix option, they're all passive : so the I/O are bi-directional, and you don't need any power at all (unless you really need the LEDs to light up).
 
That's just it. I am not merging two signals. It is only one. It will be coming down side A or side B. Not side A and B. Side A would have Bass A connected to it. Side B would have Bass B connected to it. I can only play one at a time and the signal to B will be muted when playing A. So... there's virtually no chance of there being two signals coming down the wye at the same time. I was talking with a buddy of mine last night, not sure why I didn't think to ask him to begin with (always nice to have a lead amp designer for a well known amp manufacturer as a childhood friend!) but he was saying the only concern he'd have is impedance but given where this would occur in the signal path, it should be absolutely fine. ...just don't run a signal down both sides of the wye at the same time. For that, as you pointed out, I would need a summing amp.

The Boss LS-2 can do that for you, make you chose between two input signal paths and then having them go through one output depending on which you have switched to.

You could also have one input split into two outputs ir two inputs split into two outputs, but it'll do exactly what you need.

Exactly as I already wrote in my previous post in this thread.
 

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