Is Nelson's pre as good as his amp ?

The Aleph 2 Owner's Manual says: "For the lowest possible operating noise in any environment, the amplifier is equipped with balancd inputs featuring a common mode noise rejection of greater than 60db". I basically can't find the place in manual mentioning about no penalty of using unbalanced (RCA) against balanced. However, I did see "There is no penalty for not using this plug with unbalanced oeration". "No penalty" here I think is something about using or not using the plug for RCA to switch in between 26 dB and 20 dB gains.

balanced is better if the full design is balanced. CMRR is always greatly improved with a balanced design which is always good. That is all you need to remember.

Jshaw, sorry you are right about that, I was going from memory and now that you mention it, I do remember it that way.

I have had the Pass X2.5 preamp for five months, initially into the Aleph 5 with balanced interconnects and now into the GamuT D-100 Mk. III. This is a wonderful fully balanced SS preamp. It is very quiet, with excellent clarity, smooth, great sound stage and all the other attributes of a great preamp. I think it is near world class at a value price. TAS rates the Pass X1 very highly which I've been told sounds very similar to the X2.5. These preamps are the next generation after the Aleph-P. Ultra Audio reviewed Pass X2.5 on feb. 15, 2003 and compared it with a 14K Rowland design and it was fairly close. Nelson has plenty of info on his preamp at his web site.

Ejiif:
Don't feel sorry. I couldn't remember all the details either. I actually just pulled out the manual to refresh my memory...

I think Pass would recommend to use balanced for his amps, if the balanced input is equipped. You can drop any questions to Mr. Nelson Pass and he will answer your questions. Excellent customer service!