Balanced vs. Unbalanced - What does it mean?

I would add that XLR circuits use higher signal levels - so better signal to noise or more dynamic range.

“Line-level” signal level for consumer audio equipment is nominally -10dBV (0.32V RMS). However, “line-level” signal level for pro-sound equipment is +4dBV (1.23V RMS). Simply put, pro audio gear is looking for a 14dB higher signal level.

Anyone who suspects that 14db additional signal level will likely translate into significant benefits in dynamic range would be correct (never mind the length of your audio cables). Most electronics does not perform as well at very low signal levels. Of course, it won't matter much for a hyper-compressed Green Day album but on a good recording you'll often notice a small or slight difference with balanced.

Also the "hum" that Al mentions is even more of a significant problem when using lower signal levels - not to metion the lack of shielding and the problematic grounding of chassis when using RCA. Serious audiophiles really should consider balanced before investing in things like resonator cups, as there is science as well as a long track record behind balanced XLR equipment.

Nevertheless be careful. Pro audio gear will often be too "hot" for consumer grade stuff and you'll get clipping unless you attenuate pro quality balanced signals when interfacing to ordinary consumer grade gear. RCA is ubiquitous ONLY because it is cheap and often adequate.

It would be a concern if the outputs of a pro-oriented source component, or a pro-oriented equalizer or processor, were fed into the line-level inputs or tape inputs of a consumer-oriented preamplifier

Exactly. If you use a Benchmark DAC1 with the XLR ouput into a consumer grade preamp or poweramp then you will probably need to set the attenuator pad in the DAC1 to drop the signal level by 20db. (This is wasteful of the higher ouput capability of pro balanced lines. It is generally a good rule of thumb to use higher level signals to give you more dynamic range over the equipment noise floor. It may well be enough of a difference to be able to hear something very soft or 60 db down versus not hearing it at all...)

Then, the next step is to determine what sounds best *to the listener*. In the end, that's all that matters.

I think we all agree on this but "try 'em out and see" is not helping to increase understanding. (I am sure that Cam will take this for granted - I am sure he is going to listen and see)

However, a listen and see kind of approach is exactly how sonic properties become associated with interconnecting wires when the root cause is equipment related or impedance matching or mistaken volume level matching or any of hundreds of possibilities that have nothing to do with the purity of the copper. Creating a new myth every month, week or day.

Sometimes (perhaps often) degradation to a musical source is not always inherently obvious to even a trained listener (small amounts of compression and distortion can even regarded perceptively as pleasant or an improvement). This is why there are companies like Audio Precision otherwise we could ALL, as an entire industry, simply "try 'em out and see". Sadly "try 'em out and see" is the only approach that some manufacturers actually practice. This is how you end up with nice sounding products that do not reproduce the source material with much accuracy (measure badly but are claimed to be SOTA).

To the customers of this equipment, nice sounding is everything.

Good point. I think one needs to be aware of both valid philosophies and make one's choices accordingly. I can't tell where the OP's preferences sit but hopefully both the technical and non technical advice will be helpful.

I guess all I am saying is that "listen and see" may not get to nirvana for everyone...for some it could be the holy grail while for others it may mean getting lost in a forest of near random equipment flipping/experimentation in order to get the nicest sound.

Nevertheless, I believe there's no substitute for listening, and for tuning a system according to one's tastes. Haven't you done this, or have you stopped experimenting because of your belief in engineering and specs (no disrespect intended here...an honest question...)?

You always have great points, Tvad. However, this thread belongs to the OP and is not about me.

As you correctly point out, I already said far more than my two cents worth on this thread - so I'll leave it at that. I agree with you that the OP should simply ignore what is not helpful - too much of it from me, unfortunately.