Balanced XLR to RCA Adapters: Good or Bad?

Thanks, Herman. To clarify, my no. 3 was just intended to refer to xlr input connectors, not rca's, which of course are single-ended but make no bones about it :-)

Best regards,
-- Al

The manual for the Aesthetix IO indicates on page 8 that its front-end stage is single-ended, with the second stage converting to balanced, and the rest of the signal path, apparently including a passive equalization circuit, being balanced.

So a "fake" xlr input does not necessarily equate with low quality, and may be provided simply as a convenience feature.

A phono stage could use RCAs as balanced inputs if they float the ground.

True enough.

Best regards,
-- Al

I for one wonder why the SE standard is not BNC instead of RCA. BNC would seem to have the potential to sound better.

Yes, RCA's leave a lot to be desired, including the fact that during insertion the signal pin makes contact before the ground sleeve, and during extraction breaks contact after the ground sleeve. Which means that a very large transient might be put into the system if the cable is accidentally yanked out while everything is powered up. But the superior impedance control that BNC's provide is irrelevant at analog audio frequencies, and I suppose they cost a bit more. The main reason BNC's are not used for single-ended phono signals, though, is probably just that RCA's became the de facto standard many moons ago, and no one wants to step out of line. My vintage Mark Levinson ML-1 uses Camac Lemo connectors, which are far superior to RCA's, but forces the use of unconventional cables having Lemo's on one end and RCA's on the other end, or else (gasp) Lemo to RCA adapters, which is what I use.

Best regards,
-- Al

TD, I don't know about the Cardas adapters, but the RCA-female to XLR-male adapters that I have seen connect the ground sleeve of the RCA connector to XLR pin 3, and to XLR pin 1, and to the XLR shell. If the adapter you were using was similar, it would mean that one end of the cartridge coils would have been connected through the adapter to both the circuit ground and the chassis ground of the Ayre phono stage. That would certainly figure to have adverse sonic consequences, in part because it would amount to putting an unbalanced signal into the Ayre's balanced signal path. But as I see it those consequences have no relevance to adapting an XLR output to an RCA input, as the OP is considering doing.

Perhaps some of the negative experiences with adapters that were cited by the others had similar causes?

Regards,
-- Al

I'd just like to offer some clarifications with respect to the references that have been made to "fake xlr equipment." Three different situations need to be distinguished:

1)The phono stage provides an xlr input, and has a fully balanced internal signal path.

2)The phono stage provides an xlr input, which is routed into a circuit stage that has a balanced input and an unbalanced output, the rest of the signal path in the unit being unbalanced. That retains the noise rejection benefits of the fully balanced approach, and in so doing takes advantage of the fact that the cartridge is a balanced source. "Noise" in this context refers mainly to noise that is picked up in the cabling between the cartridge and the phono stage input, which may include ultrasonic and rf noise that may not be audible in itself but may have audible consequences. This approach obviously does not provide the potential benefits of a fully balanced internal signal path, but is likely to be less expensive for comparable quality.

3)The phono stage does not have a balanced input stage, and utilizes only one of the two signals in the balanced signal pair, with the other one being connected to ground. That would merit the word "fake" that has been used, as there would be nothing balanced about the balanced input. FWIW, I am not specifically aware of any such phono stages, but it wouldn't surprise me if some existed.

The tradeoff between the first two approaches should, IMO, revolve primarily around the quality of the particular designs, as well as cost, and not primarily on theoretical considerations of balanced vs. unbalanced. Whether or not the rest of the components in the system have balanced internal signal paths is also a relevant factor.

Regards,
-- Al