XLR waste of time ?

Nrenter, you got it exactly right. That is why I am careful to stress 'properly set up' and 'low impedance' as those things are critical to getting the performance out of cables in general and balanced lines in particular.

Preamps with RCAs tend to have high output impedances which make them susceptible to differences in cable construction.

Most of the high end audio does not recognize this simple fact, because most manufacturers are doing balanced because it is something trendy, rather than researching exactly what the benefits are are and in particular **how to win those benefits**.

So as a result we have a lot of variable results that make the whole thing confusing.

In the case of LOMC, since the cartridges are an inherently balanced low impedance source, and should be loaded by a low resistance for best results, balanced is a sort of no-brainer. A great deal depends on the input of the phono section; if not differential forget it, and a great deal depends on the tone arm wiring- if the ground is independent of the signal wiring (which in most arms it is, the exception being straight-tracking air-bearing arms), then there are no worries.

JimJoyce25: It sounds as if the conclusions being voiced here are based more on philosophical creed, rather than on experimentation----at least not recent experimentation.

Since either type of connector can be used on either type of cable, the comparison should be pretty straightforward.

I've done the direct comparison of Eichmann silver vs copper RCAs. and in a good enough system, the superiority of the silver is quite clear.

I'd be interested in knowing if anyone has done a similarly direct comparison between the Eichmann silvers and high-quality XLR connectors.

Not sure how balanced cabling can be used with RCA connectors, at least in a way that preserves the benefits of a balanced interface. And vice versa as well -- what would be the point to making a comparison between connectors using unbalanced cabling terminated with XLR connectors? One or both of those alternatives seeming to be the experiment you are proposing, if I understand correctly.

And it seems to me that in any experimental comparison between RCA and XLR connectors the differences will be vastly overshadowed by other variables. As Nrenter aptly put it, "A great audio system is not a collection of optimized independent variables, but a collection of optimized dependent variables."

Variables in this situation that clearly, imo, would far outweigh differences between quality connectors of the two types include, for starters:

-- Interface circuit differences at both ends, including the fact that in designs that have XLR connectors but are not "fully balanced" there will likely be an extra active stage in the signal path to convert between balanced and unbalanced (or vice versa).

-- The fact that in most and perhaps all conventional designs the ground sleeve of an rca jack (and consequently the shield of the unbalanced cable that is normally connected to it), is common with both signal ground, chassis, and ac safety ground. Resulting in signal return currents flowing through that shield in common with extraneous ac-related currents and noise caused by leakage paths and parasitic capacitances in the power transformer and elsewhere, and also due to ground loops which are often present to some degree.

Basically, if it is not clear, connecting balanced cabling via RCA's, and connecting unbalanced cabling via XLR's, makes no sense. And the suggestion in your last post of comparing RCA tape outs with XLR main outs, in order to evaluate connector differences, is, well, simply unworthy of comment considering all of the circuitry that is present between those points, most probably including the volume control.

On the other hand, contrary to what was said in some of the earlier responses in this thread, it is conceivable (although not especially likely) that in some systems there may be significant reduction of noise pickup if an unbalanced output is connected to a balanced input via a properly implemented adapter arrangement. See figure 2.1 of this reference:

http://www.jensen-transformers.com/an/an003.pdf

Note carefully how the adapter cable is architected, with the "adapting" basically being done at the source component's output, and balanced cabling being used from that point forward. Note also that although its common mode rejection ratio is far lower than for the transformer-based interface arrangements shown in the subsequent figures, the 30db cmrr figure which is indicated as being typical at 60Hz is significant nevertheless.

With respect to the op's question, I believe that a Cardas RCAM/XLRM adapter (RCA male to XLR male), followed by a conventional balanced XLR female to XLR male cable, would amount essentially to this same arrangement. I also suspect that comparable but probably much less expensive pro-oriented adapters, available from B&H Photo Video and many other sources, would provide similar performance, at least from a noise rejection standpoint.

But whether the overall sonic result would be superior to, equal to, or inferior to the op's present single-ended connection scheme would pretty clearly have to be determined by trial and error.

Regards,
-- Al

Almarg,

Thank you for the Jensen transformer link.

Best,
Sam

Sam, you're very welcome.

And thanks very much for the link you provided to the Rane paper, in your post dated 11/24. It is indeed, as you said, very informative, and makes the point (among many other points) that a lot of balanced equipment is designed incorrectly in some of the respects we have been discussing here.

That perhaps being one of the reasons for the disagreements that tend to arise about balanced vs. unbalanced, and perhaps being an underlying reason for some cases of sensitivity to cable differences as well, as Shadorne has often pointed out.

Best regards,
-- Al

Hi, Al,

Agreed. I value your comments...Thanks for sharing your knowledge with us.

Best,
Sam