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Stereo jack wiring

C

Cernael

Jun 28, 2008
108
1
#1
I contemplate changing the jack in my bass to a stereo one, and I wonder:

Is it terribly wrong to use the "tip" as the ground connector, and use "ring" and "sleeve" as hots?

I know it's usually "sleeve" that is ground, but I would prefer to be able to use a mono cable occationally, and not have one of the "hots" shorted out before it gets to the amp. (Apparently, when you put a mono plug in a stereo jack, both "ring" and "sleeve" go to "sleeve".)
 
#2
the main reason a stereo jack is used is typically so that the extra connector is basically used to turn on/off the active preamp in a bass. If you did this to an active bass it'd surely mess something up. Also, it wouldn't avoid the problem of the "pop" you hear when you plug in an active bass, which is usually the sound of the active preamp kicking on and there's nothing you can do about that.

If the bass is passive and has no such mechanism, it might work but your signal would likely be out of phase. In either case, not a really good idea and there's generally less noise when plugging into a passive bass anyway. But seriously, you should just use the mute button or turn your amp off before plugging in.
 
#3
Um, I'm not that usual case.

The reason I want stereo output is to have the opportunity to process the signal from different pickups individually. (I actually have six pickups, 4 soapbars and 2 piezos, divided evenly between two necks, and plan to have two stereo outputs, but that's a later issue.)

Thing is, I want it to be thusly: If I plug in a stereo cable, the signals should go to different outs, but if I plug in a mono cable, I want all the outputs to go through to the same place.

(OK, just got it; in the stereo case, with a standard Y split cable, only one channel would have ground...that'd be bad. Guess I could rewire the cable?)

And how could it be out of phase? Out of phase relative to what? All the signals to my amp will come from my bass anyway.
 
#4
This would definitely break the function of a standard Y cable for sure, although you could just make your own if it really mattered that much. Your setup sounds pretty complicated, with that amount of customization, i'd almost question why not use some kind of switch to do this instead? Or perhaps using some kind of custom jack for that setup and then a 1/4 jack for a normal output (since you're planning adding another jack anyway) I'm sure you could find a 5 pin din plug type of deal that would work for this and would probably be a lot cleaner of a solution than using 2x1/4 jacks in a not so usual way. Kinda like how a lot of those old alembics had that special jack.

Generally plugging any sort of audio equipment in backwards will make it out of phase, essentially the speaker moves in the opposite direction to make the sound as it's receiving the signal 180 degrees out of phase. In the case of a mono signal, you're right, it's just out of phase to itself, but if there's other instruments playing that are in phase, this could very well cause problems. You'll note there's plenty of preamps and such that have "phase" switches on them to reverse the phase in situations like this. Out of phase sound can potentially cancel out other sound in the same frequency from other instruments and such.
 
#5
Thing is, I found these stereo jacks with built in dpdt switches (that are triggered by inserting a cable; StewMac has them, as does Banzaieffects in Germany, which is a little closer to me). I figure those switches could be wired to take care of getting the signals to the right outs just by plugging the bass in, which would be neat.

And I still disagree on the out of phase thing; oop is a relation, not a quality onto itself. It'd be oop compared to how it would be if I wired it the other way, but since I didn't, the point is moot. And in order to be oop with ANOTHER instrument, playing at the same time, we'd have to make sure the signal comes out of the same speaker, in addition to timing the attack so that the signals start at the same place in the phase. That's, IMHO, not very likely to happen.

The "same speaker" thing would happen when playing back a recording, granted, but OTOH, general phase stuff is one of the things you should check for in the mastering process anyway.
 

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