Pass Labs Aleph Question - balanced vs unbalanced?

Right - but remember I have no hum in my system on RCA cables at full pre-amp output and CD player having just played music and then hitting pause and turning pre-amp all the way up...

So in that case then there is no reason to convert back and forth, right? If I have no RCA hum, then is there any sonic reason to use balanced?

The only "sonic reason" should be that one way sounds better than the other and that's up to you. Sometimes the differences are very subtle and it's hard to tell. Seeing as your pre is not a fully balanced unit, the signal would have to be converted to balanced, then when it gets to the amp, which is not balanced, it would have to be converted again. Seems to me the rca would stand the best chance of sounding better if there is no noise getting into them. If you don't hear an obvious difference, listen again for a little more soundstage, depth, holography etc, with the rca's. Good luck.

Pass aleph amps are balanced (differential) I've looked at the schematic. They are single-ended in that they are not push-pull. This is a different use of the single-ended terminology. They do benefit from a balanced connection to the preamp.

Wloeb - I thought something like that may be the case - because Nelson Pass says in his materials that air is single ended in how it relates to sound and that made me think the words meant something else...

Okay - so the Pass Alephs are internally balanced? So if I go RCA, the RCA input has to be converted to balanced? That makes sense... I had thought they were fully balanced years ago.

If an amp is balanced internally then its got to be at least a hair better with balanced inputs - even if that hair is not discernable. (Because of additional conversion step).

Oh - but then there are those who might say that conversion could improve the sound and we get into our basic audiophile philosophy about equipment...

Bottom line - amp is internally balanced, so balanced should be better - recognizing that one needs to listen for final conclusion as odd things happen in complicated systems. Cool.

If you use RCA (single-ended) interconnects, make sure you keep the jumper pins to connect #1 and #3 on both XLR connections. Otherwise, you will loose some dB when using single-ended cable.

You brought up an interesting point regarding terminology. I remember 10 years ago, I had read on Stereophile referring RCA connections as "sigle-ended" connection and used that on one of the online forums and was laughed at for misusing the term as at that time the term was mostly used to describe tube circuitry as others have stated.

FrankC