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Pass Laboratories X150.5 Stereo Power Amplifier Print E-mail
Saturday, 01 November 2003
Article Index
Pass Laboratories X150.5 Stereo Power Amplifier
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After casually playing the Pass X150.5 in my system for a couple of weeks, I started my serious listening with Lightbulb Sun (Snapper Music), a year 2000 release from one of my current favorite artists, Porcupine Tree. I have been a fan of theirs for years, dating back to their early ‘90s spacey, progressive days, which were dominated by songwriter-guitarist-vocalist Steve Wilson. In the last few years, they have slowly evolved into more of a concept group, and their more cohesive and song-oriented albums show it, with less of a classical progressive wandering feeling. The title track leads off the album with crisp acoustic guitar, breaking into Porcupine Tree’s trademark punchy and dynamic kick drum and bass-fueled electric guitar riff. As the song climaxes, the fluid lead guitar competes with the raucous synthesizer, bass and drums, and the X150.5 expertly pulls the melody out of the mayhem. The delicate, harmonic side of the Pass Laboratories amplifier is evident on the Beatlesque track, “How is Your Life Today?” The purposely muffled lead vocals that open the song give way to Wilson’s clear falsetto, finally leading to beautiful, layered harmonies. Through the Pass amplifier, the soundstage goes from very small and intimate to large and wide as the single voice expands to many, and the snaps and clangs of the percussion and keyboards expand the image even more, before it shrinks back into a solid, center-focused small image again. The X150.5 was very impressive during this cut that I know so well, bringing out added three-dimensionality that I had not noticed to this extent before. The low end throughout was never bloated or overemphasized, occasionally causing me to wonder if something was missing, until suddenly it would appear with surprising power and impact. Also noticeable on this album was the extremely low noise floor, the music seeming more dynamic, not by perceived louder peaks, but by relaying the low-level portions with increased relative dynamics. With relatively efficient loudspeakers, such as the Paradigm Reference 100 v.3s, you can crank it to your heart’s desire without running out of steam with the X150.5. “Russia On Ice,” a classic progressive opus, really came alive. As I cranked it up, it moved the music up and down the rollercoaster of this exciting cut, and me right along with it.

In the mood for a little blues on a lazy Saturday afternoon, I selected Sam McLain’s acclaimed sonic jewel, Give It Up For Love (AudioQuest Music). I had forgotten how great this music and recording is, but the X150.5 immediately reminded me. This is how a band should be recorded, with big and powerful bass you feel in your gut, live percussion that jumps and snaps with the striking of the sticks, and vocals prominent, gritty, and clearly placed out in front of the band. I don’t know how to say it any other way than that it was easy to picture McLain standing and singing between the speakers, not smooth and gentle, but full of pain and emotion. Forgetting about the review, I threw my note pad down and let “What You Want Me To Do” rip, the bass slamming, the guitar and drums brash but still melodious as live music is and should be. Despite the fact that I could do without the occasional cheesy, soap opera organ riffs, I had a blast listening to this album through the X150.5. The Pass amplifier appropriately shrank everything down on gentler, simpler tracks such as “Don’t Turn Back Now,” the crisp cymbals jumping out of the silent background, the vocals intimate but still powerful, up front and center. Why can’t more music be recorded like this? One piece of advice – don’t play Give It Up For Love at the beginning of a listening session. It is too hard an act to follow, and most things will sound compressed and artificial in comparison.

Like many folks, I have been playing a lot of Johnny Cash lately as I grieve his recent passing. I am not sure how he managed it, but somehow he stayed interesting and relevant throughout the last 40 years across a wide variety of music genres, as is clearly evident in his 2002 release, Unchained (Sony Music). This is a wonderful album, well recorded, featuring great and varying original pieces and covers, with Tom Petty and the Heartbreakers as a backup band to boot. Cash’s vocals are clear, yet gritty and edgy where appropriate. The X150.5 portrayed the bite in his voice and the closely recorded acoustic guitars, but did it in a way that was not fatiguing to me, detailed and mercilessly revealing, but not brittle. The bass was lean and tight, but not so lean as to be overly polite. The Heartbreakers provide excellent backup, tastefully staying within the songs and in the background, with a few exceptions. One of these is the surprising and rocking Soundgarden cover, “Rusty Cage.” Midway through the song, the Heartbreakers were unleashed, the X150.5 setting the room on fire. If I detected someone sitting still during that tune, I’m afraid I’d be forced to kick them out of my house. Another tasteful reincarnation is the cover of the Heartbreakers’ own “Southern Accents,” which showcased the Pass X150.5’s ability to cover the full range of the throaty and rumbling vocals that only Cash can do.

I spent a very interesting period with a bare bones system, consisting of an Underwood HiFi modified Shanling SCDT-200 SACD player directly connected to the Pass X150.5, which in turn drove a pair of Revel Salons. This was one of the most enjoyable listening experiences I have ever had. The Pass Laboratories X150.5 and the Shanling SCDT-200 presented a truly beautiful, artistic and synergistic pair both sonically and visually. The gentle blue lights and classy front panel of the Pass X150.5 matched perfectly with the retro space age industrial design and similar neon blue lighting of the SCDT-200. With the lights dimmed and the music flowing, I was in audio and visual heaven. The X150.5 clearly differentiated between the Shanling’s softer, rounded tube outputs and the subtly but distinctively different direct outputs, with their additional detail, tautness and clarity. Guitar legend Ronnie Montrose’s Music From Here (Fearless Urge), perhaps his most tasteful album to date, was fantastic through this system. The underlying gurgling, water-like synthesizer in the gentle but complex “Fear Not” was clear and detailed, yet appropriately placed in the background. The bass guitar had good weight, in balance and solid but not bloated. The driving beat and rounded guitar of “Road to Reason” contrasted spectacularly with the sparkling, utterly lifelike cymbals and percussion. The Pass X150.5 clearly was able to rise up to the task of driving the demanding load of the Salons. Not until I cranked the inefficient Salons to extremely high levels did the X150.5 begin to run out of steam and the sound to slightly harden.


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