help requested for simple design

[Lotus 7]

Originally Posted by Mr XY

Hi Tech geniuses!

I'd like to make a little box that has two functions:

A: switches between 2 balanced stereo sources

B: Switches between normal output and L/R channels reversed (not polarity - just literally swap left and right - i find it really useful as my ears are not as as symmetrical they should be!)

So it would be two sets of stereo balanced inputs going to one stereo balanced output (all on xlrs)

I can solder well and follow a diagram, but am clueless as to what parts I should use (and where to buy them) Have a suitable box already, not bothered whether rotary or toggle switches. This is for my monitor path so audio integrity is key.

Any input really appreciated - thanks!

It can be done with a couple of 4-pole double throw switches (probably best to use rotary switches, but 4P-DT toggle switches are available). If your chassis box is metal (to maintain shielding), then plain wire can be used. If the box is non-conductive, then it would be best to use shielded wiring (a lot more work).

This circuit maintains correct polarity and is fully balanced.

Jameco or Mouser can supply the parts (switches and chassis mount male and female XLRs).

Schematic attached below:

[Mr XY]

Thank you so much for this!! amazing!

If i could ask one more thing - does this seem like a good chice for the switch?

http://www.mouser.com/ProductDetail/...2eAdVnme5SU%3d

Or if you could please recommend me what you would use?

Thanks again!

[Lotus 7]

Originally Posted by Mr XY

Thank you so much for this!! amazing!

If i could ask one more thing - does this seem like a good chice for the switch?

A402S1RNCBE C&K Components | Mouser

Or if you could please recommend me what you would use?

Thanks again!

That looks like an excellent choice. The large silver contacts will have low contact resistance and it's a "non-shorting" action which will keep the L & R channels from being momentarily connected together when the switch is rotated (although that's really not an issue for line-level" signals). A pair of those will work fine.

When working with a "new" multi-pole switch for the first time, it's often a good idea to confirm the connections with an ohmmeter. Check each of the poles for the connections in Pos -1 and then physically change the switch to Pos-2 and re-check that the other poles are actually connected as you expected.

A lighter duty switch would also work fine - Mouser has some Push-Button slide action 4PDT units that will work, but if I were building it, I'd use the rotary switches so there is no doubt about which source, and which stereo orientation is selected.

Good Luck with your project!

[Mr XY]

Thanks!!!!!!!!