Balanced 3.5mm connector?

Jim R. · 5723

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Offline Jim R.

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on: February 15, 2012, 02:55:43 PM
Ok, I must be living under a rock because I had no idea these existed until today when I was shopping for some 3.5mm plugs and jacks on the markertek site, but apparently there is such a thing as a 3.5mm TRRS plug and Jack (though not made by switchcraft).

Has anybody used these and can tell me more about them?

Here's my thinking:  I would wire the tip and next ring as usual with left and right positive connections as normal, and then the next ring would be either left or right minus or return, and the sleeve would be the other channel's return.  If my thinking is correct then hopefully the balanced plug would work in unbalanced, TRS mode when plugged into a standard 3.5mm TRS jack, and likewise, a standarrd 3.5mm TRS would work normally  when plugged into a TRRS jack.

If this will work, I'd like to put one of these trrs jacks in my Smack and maybe s.e.x. 2.1 as well, and then have somebody rewire the 3.5mm TRS plug on my Shure IEMs to a TRRS, and hopefully still be able to use it with the iPod, my ALO Continental amp, etc.

So, if anybody can confirm that his will work and especially if anybody knows who has the soldering chops to swap the connectors for me, that would be great -- I'm afraid that such fine soldering is not going to be something I can manage, or at least very well, and the Lune silver cable was pretty expensive and I don't want to mess it up.

Personally, I think this could be a really cool solution to a balanced pair of IEMs.

Thanks,

Jim

Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)


Offline Paul Joppa

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Reply #1 on: February 15, 2012, 04:49:05 PM
In the Smack, when using the higher impedance settings, both center taps are grounded. So the standard TRS plug with your suggested wiring would also connect the negative signal, and through transformer coupling the two channels would be shorted together, giving a mono signal. At the lower impedance settings, the resistor divider would do something similar but not as severe.

Something to do with sow's ears and silk purses I think. Or free lunches.  :^)

Paul Joppa


Offline Jim R.

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Reply #2 on: February 15, 2012, 05:09:33 PM
Even with the switch boards and seleccting thebalanced output?

Maybe I could make an adaptor cable to connect the 3.5mm trrs to the two 3 pin xlrs?  Assuming this adaptor would be used with only the trrs plug and balanced mode on the amp?

Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)