Wiring a differential output with an audio transformer

Hi guys, I would like to put an audio transformer at the differential output of MAX4063 chip.

This transformer has a center tap. Then at secondary side, outputs will be connected to a 3-pin XLR cable (eg 10m long).

Is this a correct wiring?

I couldn't find anything similar with Google.

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Thanks!
 
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Dont ground centre tap on either primary or secondary. Leave it unconnected otherwise you end up with all sorts of phase shifts. Look at the jenzen audio transformer website they have connection diagramms on how to use transformers correctly. You can apply the principles to your transformer.good luck.
 
If you're after high quality audio, that's the wrong transformer. The frequency response is terrible, and I would anticipate the distortion figures will also be horrible. When it says +/- 2dB at 300Hz, you can expect more than 2dB roll off at 300Hz, and that means 20Hz will be out of the question. Those are designed for communications and modem circuits, not audio. Even people after transformer saturation will hate that one.

Good audio transformers for line level are always bigger and more expensive.

The other thing to remember is a transformer's impedance rating is a recommendation for source and load, not the real impedance of the transformer. And if you do drive it from the recommended source, you should also terminate it with the recommended load.

If I might ask: What's the application?
 
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per transformer datasheet, it is 600ohms for primary and same for secondary. other end of the XLR cable will be connected to LINE IN of behringer ADA8200.
Don't think the MAX4063 will drive such a low impedance well, 600 ohm differential is 300 ohm on each output, and the datasheet suggests the outputs are around 75 ohms output impedance rather than the <0.1 or so of a standard opamp closed loop.

Also its got some rather troubling specs, like input voltage noise of 70nV/√Hz with a gain of 20, despite having 12nV for gain of 200 - this suggests the output stage is very noisy and can only be finessed at high gain.
 
If you're after high quality audio, that's the wrong transformer. The frequency response is terrible, and I would anticipate the distortion figures will also be horrible. When it says +/- 2dB at 300Hz, you can expect more than 2dB roll off at 300Hz, and that means 20Hz will be out of the question. Those are designed for communications and modem circuits, not audio. Even people after transformer saturation will hate that one.

Good audio transformers for line level are always bigger and more expensive.

The other thing to remember is a transformer's impedance rating is a recommendation for source and load, not the real impedance of the transformer. And if you do drive it from the recommended source, you should also terminate it with the recommended load.

If I might ask: What's the application?
application is for an industrial mic. Mic freq is 400Hz to 6000 Hz:
https://shop.gentexcorp.com/gentex-boom-microphone-m175a-vrc/

so all I need to do is keep the centre taps of both primary and secondary not connected?

so what is connected to SHIELD pin of the XLR that will be connected to secondary side of the transformer?
 
Have you tried it without the transformer? Any balanced input with reasonable CMRR should work fine like that. But I’d try it before falling back to a low quality transformer.

Also, in balanced audio transmission the common mode rejection ratio at the receiving device is where the noise immunity happens. If the transformer should be anywhere (and I’m suggesting it might not be needed) it should be at the receiving devices input.