Pass Labs XP-20 Stereo Preamplifier


In Use

For the listening tests, I used an OPPO BDP-95 universal player, Classé CA-M600 monoblock power amplifiers, and Carver Mark IV ribbon speakers. Cables were Emotiva, Marc Audio, and Legenburg.

I was totally unprepared for the amount of detail that was presented to me in the music I played using the XP-20 preamplifier. It is none of that "There was more air around the brass," or, "the background was blacker," kind of thing, which are simply prosaic ways of saying there is less distortion, and in particular, less IMD. It was simply that absolutely every nuance was audible. When you look at the bench tests, you will see why.

Even this classic Miles Davis jazz album that was originally released as an LP, and subsequently re-issued on 45 RPM LP, CD, and SACD (the version I listened to) delivered incredible detail. Brass is notorious for being harsh when there is significant distortion, but Mile's trumpet was as smooth as silk. The sticking on Jimmy Cobb's cymbals had the kind of detail I am used to when playing my own cymbals. Just when you think you have already heard everything the recording has to deliver, you discover something new. Wow!


Stravinsky's Firebird is not exactly background music, and the XP-20 brought it even more forward. Just abolutely amazing. It's wonderful to be able to hear every instrument separate from all the others, rather than sounding like they slightly overlap, due to the mushiness produced by distortion products. There are some sections in this piece where the full orchestra is going at it, and I think even the stage hands must have been playing harmonicas and kazoos. I heard it all.

I tend to visualize scenes in my imagination when listening to music, and in Track 1 ("Introduction"), I visualized a submarine lurking below the surface of the Atlantic in 1941, and seeing a target, prepares the torpedoes to attack the ship. If the music sounds mushy, I have less visualization. It's cloudy, as the music is not crisp and clean. Well, I could hear the Captain requesting the bearing of the target, and shouting, "Fire 1." Great visualization. Wonderful preamplifier.


Now here is an album to test the bass capabilities of your audio system. I have plenty of power and big speakers, but a preamp with a weak power supply would roll off the low end. I heard every rumble, thump, and bass drum pounding away. Nope. No shortage of preamplifier drive capability here.


Pipe organ is the ultimate deep bass test, and Bach is King of the Organ Music Composers. The low pedal tones rattled the studs in my wall. Again, the power supply of the XP-20 stood the test.