How do you wire a AB box with xlr male and female plugs?

Spewbag

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I either want to make a kill switch that shuts off my acoustic guitar going to the mixing board or a box that switches the acoustic guitar to my electric guitar that uses 1/4 audio jacks.
 

anwaypasible

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the first thing you need to do is check the pins of an XLR connector.
wikipedia states that:
pin 1 - chassis ground (cable shield)
pin 2 - positive polarity terminal (hot)
pin 3 - return terminal (cold)

you might be able to simply add a switch on pin 2 to turn the guitar output on/off.

otherwise you are looking for an AB switch with xlr connectors.

to make a very simple AB box.. you can use three switches, one for each pin.
i'm not talking about on/off switches here.
you would want to use A/B switches that lets you select one or the other.

xlr to 1/4 inch jack adaptor usually just ignores pin 1
but if you decide you want to use an xlr cable with a 1/4 inch plug on the end.. you could try to touch pin 1 to the metal of the computer chassis.
but usually you only need to do this when there is electrical noise interference.

if you want to have a kill switch for the A/B box.. you take the outputs of the switch for pin 2 and use an on/off switch.
having two switches for each XLR cable isnt as fancy as using a prebuilt A/B switch with only one switch.. but placing the two switches side by side isnt very hard to flip both switches at the same time.

i would start with that and see if the switches cause a big difference in the way the guitar sounds.
using an A/B switch always has the potential of affecting the sound.
one switch might while another switch might not.

if you dont like to solder or are afraid to try.. there are switches that have 'set-screw' terminals.
you simply screw the wire down onto the tab to secure it in place.

using a 'ring terminal' at the end of the wire might make things better.. or it make make things worse.

**edit**
forgot wikipedia link:
http://en.wikipedia.org/wiki/XLR_connector
 

Spewbag

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First, thank you for helping and helping timely! :)


I think I should explain better (i don't think I did originally) I basically have an idea to have two xlr plugs(male/female) and two 1/4 mono plugs in one box. The XLR's are exclusive for the Acoustic guitar and the 1/4 mono plugs are exclusive to the electric guitar. what I Would I like to do is switch back and forth between the two. When the electric is on the acoustic will be out of the circuit and vise verse or if that impossible to simply able to turn off the acoustic so I can play the electric.

Thanks again for the help
 

anwaypasible

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ah..
you want to 'map' the 1/4 input to the XLR output and/or the XLR input to the 1/4 output?

that would require an A/B switch.
one wire for the XLR on the A pin .. one wire for the 1/4 on the B pin
then just flip the switch back and forth.

again, you would need a switch for each wire.
that would be four switches total.

they make different size toggle arms.
if you get some small enough, you can flip both switches with your thumb and flip the other two switches with your pointer finger sideways.

there wont be any circuit contact unless the voltage is so high that it creates a spark (or static) between the toggle pin and the input pin.

this is the most simple and easiest way to do it.
i dont know how to wire a circuit so that you can use only one switch for a XLR to 1/4 toggle.
and wiring a circuit to have one switch toggle all XLR to 1/4 would be more difficult.

you do know that they make plain empty plastic boxes for electrical hobbies such as this?
you could put your inputs and outputs in the box with all the wires hidden inside so it looks presentable.

if you are looking for the more complicated way of wiring a toggle switch.. try www.diyaudio.com
they talk about repairs and soldering circuits all the time.. therefore you should be able to find somebody who will tell you how to wire it all up.

i think doing it the more complicated way could hurt the soundquality if you use a bunch of obnoxious components in the circuit.

i'm starting to think that maybe you can use relays to switch between connection types.. but you would have to provide power from a battery or power pack to give power that the relays need to flip their switch.

that would require you to get four relays and an on/off switch.. plus some wires and a power plug for whichever method you choose to provide power.

you hookup a positive pin from the XLR cable to the A pin of the relay.
then hookup the positive pin from the 1/4 cable to the B pin of the relay.
do the same thing for the negative wires.
then you hookup the positive and negative to the relay power inputs with the on/off switch in-line.

one side will always be connected when the relay isnt given any power.
then you flip the switch and provide power to the relay and it will change from A to B

there are other relays available because you can hookup both positive and negative to the same relay and switch both at the same time.

the simple relay that flips from A to B one wire at a time (either the positive wire or the negative wire) is called a 'single pole double throw' relay.
the relay that allows you to connect both positive and negative wires to a single relay is called a 'double pole single throw' relay.

you dont have to have four relays.. you can use one relay for each XLR to 1/4 switch.

but there is nothing said about hooking up all of the wires to one single relay.

anyways.. i guess i do know how to build a circuit to make your own A/B box.
i forgot relays could switch A/B
all i remembered was that they were on/off
and i was way off into wonderland thinking about using capacitors and resistors and diodes to make a 'print out'
ugly imagination of mine..!

i would say use a 12v DC power pack that plugs into a wall.
you could probably use some batteries.. but they go dead at all the wrong times.

if you want to see a diagram of how the relay pins are have a look here:
http://en.wikipedia.org/wiki/Relay
you will find the diagram under the 'pole and throw' section.