Balanced or Unbalanced?

No offense to the balanced proponents, but there seems to me to be an aspect that is not often discussed about balanced systems. To be truly balanced, you must have the equivalent of two systems, which are then compared to each other in some way (subtraction, division, etc.) to provide the output. If either of these systems changes once they are initially calibrated, problems may result. In addition, you are now talking about twice as many components which can add their own unique signature, as well as drift in value as they age.
As an analytical chemist by trade, my analogy is a dual-beam optical system for a spectrometer: instead of simply having a single beam of light which is used to interrogate a sample and determine its chemical composition (a single beam system), sometimes it is preferable to use a dual-beam system; the light from the source is split into two beams, a reference beam and a sample beam. The reference beam passes through blank sample (water for example) while the sample beam passes through a solution of the sample. The spectrometer then subtracts the spectrum of the reference beam from that of the sample beam to provide the corrected spectrum. This type of system is excellent at correcting for errors due to background in the solvents or drift of the optical source.
It is not always the case that a dual beam system is preferable for your analysis. A dual beam system can subtract the influences of a blank automatically, but that blank is not contained in the same vessel (cuvette in chemistry terms) as the sample, and the reference optical path is not the same as the sample optical path. Also, as mentioned above, the dual path can create problems when components age differently.
So to me the argument is not as cut and dry as it may seem at first. If you do not need the error correction afforded by a duplication of component paths, perhaps you are better off without it, as it may introduce unnecessary complication and expense to the system.

To add to my previous post (too quick on the submit button), an additional disadvantage of dual beam systems is that you halve the power of your source to create the twin beams - in some cases that creates an unacceptable loss in sensitivity to low level components. Is there a direct analogy of this phenomenon in audio systems?

Ait, you don't have these issues when dealing with a balanced line system, which normally will use about 25-50% more parts to execute than single-ended; definitely not double!

Dave, The balanced line system **is** a standard. Unfortunately many high end audio manufacturers do not adhere to it. To do it right, the driving circuit should have a low impedance, as often the input has a much lower impedance too, though not always. The significance of the lower impedances is that it swamps out cable construction issues. That makes long distances possible, and reduces the possibility of noise interaction (even in short runs). The twisted pair that runs inside the cable, being differentially driven, is also more immune to noise pickup and capacitances are also more controlled.

I concede that balanced connections have become 'stylish' and there are a number of companies that have installed connectors on their equipment that really don't come close to meeting the standard- the result being very much like what you have described. My point is that if you hear what the standard actually offers- well, there's no going back.

I agre with you, Lush: Too much deliberately confusing info is being set out there by manufacturers. It's why I'll only buy from manufacturers, like Ralph, who will talk with you if needed for you to understand what you're getting.

Atamasphere, are you saying that my Rowland is NOT truly balanced?? That would surprise me greatly, since Rowland is reputed to be one of the first to adopt a balanced configuration in consumer electronics.

I think my Rowland is truly balanced and I can hear a difference between cable brands. Your allegation is that I shouldn't be able to hear a difference in balanced mode.

Dave