XLR vs RCA

I am with Warrenh. Even though Audioengr's points are valid, the last one is the biggest concern with balanced systems, the impossibility of designing a truly balanced system.

A system that is balanced from beginning to end is actually two chains of amplification. From source to preamp to power amp you have one string of amplifiers amplifying the inverted signal and a different string of amplifiers amplifying the non-inverted. These two signals are combined at the speaker. Even though they should be the same, with tolerances in components it is impossible to build two identical amplifiers.

It is highly unlikely that both signals will be treated exactly the same throughout this process so the reconstructed signal at the speakers is distorted. Yes, there are distortions in single ended systems like in all systems, but this one introduced by the balanced systems is not present in a single ended system.

Also, digital signals start out being single ended on the disc and must be converted to balanced somewhere along the path. This is another source of distortion.

As for noise rejection, balanced does have the theoretical upper hand on long lengths of cable. But with cable lengths and the amplitude of the signals in a typical system you could not tell any difference.

Hi Subaruguru, I said they were combined at the speaker. Not that they were unabalanced. The electrical signal that is applied to the speaker terminals is balanced but the motion of the speaker is not.

Each driver can only move in one direction at a time, The cone is either moving in or it is moving out but can't go both ways at once. So in that sense it's motion is single ended.

I agree that there are well designed, great sounding components in each camp. Since I am firmly in the camp that simpler is better, I'm going with single ended. I'm using a passive preamp, my power amps have 2 tubes each, and my speakers only have one driver.