Difference between Pass Labs XA160.5 an X600.5?


Hi all,

I currently own a set of Parasound JC-1's to drive Dynaudio Confidence C4's. Although they match very well, I currently look for ´the next step`. Based on several reviews I read, Pass Labs seems to be a very good substitute for the JC-1's. I doubt however if the XA160.5 are powerfull enough. Why? Today I integrated my Velodyne DD-18 with the C4's and I heard the soundstage changing when I but my Velodyne DD-18 subwoofer on/off (at a crossover frequency of 50Hz). Apparently my 800W RMS JC-1 (into 4 Ohm) can't drive the C4's full range?!? The price difference between the XA160.5/XA200.5 and X600.5/X1000.5 is however significantly (i.e the price of a XP-20 I intend to buy). X600.5 is class A upto 80W (so seems are safer alternative than the XA160.5).

I will try to listen to both amplifiers on short time notice here in the Netherlands, but has anyone already heard both these amps and if so, what are the difference?

Thanks!
jean_sibelius
Bondmanp, those with more restricted budgets might argue that ...it almost doesn't make sense to sell the A models unless there is a regular need for extremely low output power, like very efficient speakers in a small room. :-)
I have owned the XA160, X600.5 and XA30.5 and ended up preferring and keeping the X600.5. The X.5 line is of course more powerful than the XA / XA.5 line, and I'm sure you know that. But there are other differences in the character of the sound which must be taken into account. The XA / XA.5 line is sweeter, darker, more relaxed and mellower sounding, whereas the X.5 line is faster, livelier and more dynamic sounding (greater PRAT). I find the XA / XA.5 best for vocals and small ensemble music (jazz, folk, classic rock, etc.) , whereas the X.5 is decidedly better for large orchestral works which is the bulk of what I listen do.

I could have very happily lived with the XA160 as well. OTOH the XA30.5 was very underpowered even when driving highly sensitive speakers for the type of music I listen to.

Bottom line is you must listen for yourself because it is very subjective.
I've owned the X600.5 and now have the XA200.5.

As good as the X.5 series is, it sounds hard and 2D compared to the XA.5 series. For large orchestral pieces, the suitably powered XA.5 series wins easily because the climaxes remain sweet and undistorted. The X.5 gets harsh and glassy at peaks.

There were some changes from the XA to the XA.5, which I wonder may have resolved some of the issues with peak distortion and the sense of unlimited power reserve.

I've posted my thoughts and descriptors of the XA200.5 on the forum if you do a search. The descriptors remain true even today. In my view, the XA200.5 is a masterpiece, with the only downside of heat. My amps are the muscles in a synergistic combination with key components of preamp and cabling. As good as the amps are in isolation, the BAT, Jade, Tripoint, NVS Sound combination has taken things to another level.
It comes down to personal preferences. Some people swear by the dark, liquid, and velvety sound of pure class A, while others prefer more neutrality, speed and dynamics. The question isn't whether the XA200.5 is sufficiently powerful, it's that it sounds fundamentally different in character from a class AB design. Some people, myself included, actually prefer the latter, as do the many people who buy state of the art class AB designs from ARC, MBL, D'Agostino, etc

If your X600.5s were exhibiting glassiness, it was probably caused by component matching, AC quality or cabling.