Review: Pass Labs X-1 Preamplifier

Category: Preamps

I recently obtained a Pass Labs X-1 preamp to try out in my system out of sheer curiousity.
Boy, did I make the right decision!
I had recently been using a Parasound P/LD-2000 preamp in my system, and before that a Stan Warren modified Adcom GFP-750 preamp.
These preamps were pretty good, but they always had something that added to, or took away from the sound of my system.
I listen mainly to pop, rock, r&b, and some jazz and country. I want sound that is immediate, open, transparent, very detailed, dynamic, fast, excellent bass that is deep and tight, treble that is very extended on top, and a slightly forward perspective to the sound.
I don't like grain, etch, glare, hardness, or brightness, and I don't like an overly warm, laid-back, or rolled-off sound.
The Pass Labs X-1 in combination with my Parasound Halo JC-1's gives me everything I want and so much more!
This is the best preamp/amp combination I have heard in my home, or anywhere else for that matter!
I was totally amazed when I hooked the preamp up in my system! This thing flat-out cooks! And rocks! And sings!
Combine the talents and genius of John Curl and CTC Builders with the talents and genius of Nelson Pass and Wayne Colburn, and you have EXCEPTIONAL, FIRST RATE SOUND.
The Adcom GFP-750 is a good preamp and a bargain, but it simply is not in the same league as the Pass! The Pass lacks the Adcoms slight grain, etch, recessed lower midrange and dark vocals. The Pass is more open, detailed, transparent, more energetic, more dynamic, smoother, and more neutral than the Adcom. The Pass has much more body, immediacy, and more dimension to the soundfield.
The Pass is more detailed, smoother, more transparent, and more 3-D than the Krell KRC.
The Pass is more open, transparent, detailed, more lively, and has tighter and deeper bass than the Parasound P/LD-2000.
Regardless of what others may say, the Pass Labs X-1 is a fairly good improvement over the x-2.5. I have owned both.
The Pass X-1 is slightly more open, more refined, more transparent, and has better imaging and less noise than the 2.5.
The things that impress me most about the X-1 are:
1. The extremely well controlled bass. It is subterranean deep and very powerful, yet very tight! It can fool you into thinking that it is lacking in bass, but it is not at all! Try some material with some deep powerful bass, and it will rock your world...and your foundation as well!
2. The smooth, palpable, full-bodied, and extremely detailed midrange. I can hear subtle details, reverb trails, and other nuances that I could not make out before.The sense of dimensionality, and space within the soundstage is uncanny! Vocals are exceptional, palpable, full-bodied, and real! Instruments sound very life-like.
3. The top-end is open, extended, extremely clear, and transparent without any hardness or brighness at all, unless the recording has it. The Pass is extremely revealing of recordings and associated components.
4. The dynamics, neutrality, utter transparency, and liveliness of the sound! If you like a fast, dynamic, and lively sound, the Pass should be your preamp! It is NEVER boring! It is extremely fast, clean, and energetic without being aggressive, bright, or harsh. These Pass units have to be some of the most transparent active preamps available!They have an extreme "see-through" quality to them that is very appealing. This also the most neutral preamp I have ever heard.
If the Pass X-1 has any weaknesses, it would probably be in the area of tonal color, texture, and organic naturalness?
Also I heard a passive preamp once that seemed to have VERY slightly better "air", and maybe a tad more top-end extension or treble detail, but not by much at all! The Pass is still a much better preamp top to bottom, in my opinion.
As a final note, I thought for a while that my JC-1's might have some sonic weaknesses such as a slightly cloudy midrange and top-end, slight lack of transparency, slight roll-off on top, and a lack of depth and dimensionality,
but NO MORE!
After I installed the Pass X-1 all these perceived weaknesses seemed to completely go away! I am still totally amazed at this combo! I can now sit back and enjoy my music all day long without worrying that somthing doesn't sound right, or wondering what should I upgrade next! Well, I do wonder how good the Pass Labs X-0.2 would sound! But the $$$ is too much of a factor there!
I highly recommend the Pass X-1 preamp without reservations!

Associated gear
Sony XA-777ES CD/SACD Player
Modded Pioneer DV-47Ai universal disc player.
Parasound Halo JC-1 monoblock power amps
Paradigm Reference Studio 100 version 2 loudspeakers
Lat IC-200 MK.II interconnects
LAT SS-1000D External bi-wire speaker cables

Similar products
Adcom GFP-750
Carver CT-24
Krell KRC
Parasound PLD-2000
Parasound Halo P-3
Pass Labs X-2.5
Rotel RC-1090
The Pass is a great preamp. However, it ultimately didn't satisfy me in the midrange. I found voices to lack a coherency and life to them. As a vocalist and instrumentalist, I am quite sensitive to the "lining up of harmonics." For example, on my Rogue 99, or even the ARC LS-7, you will hear on voices the cavity & chest resonance, accompanied by the focus & ping that shoot out into the air (partially this is the upper harmonics). And this will all be integrated into one sound that makes it sound like a real voice.

On the X-1, the deeper resonances were shrunken, and the disconnected from the upper harmonic focus & ping. This was with both the older and the updated boards. There was a certain coolness, an analytical quality that I ultimately found disappointing. The ARC solid state LS-12 did much better in this regard. Listening to "Stompin' at the Savoy" (Chesky JD1, Pizzarelli guitar duet recording Once again, the cavity resonance of wood guitar body is integrated with the initial pluck attack, and the complex harmonics ring and spring out into the air, and all of this is integrated as one complete sound. The other preamps mentioned could do this, but the X-1 could not. Sorry, but that was my experience.
I had the complete opposite experience with the X-1, while it did not provide some of the lushness with SOME tube amps I tired, I did find the voices had the cavity & chest resonance in my system, maybe too much on come CDs. It was one of the most dynmaic preamps I heard and was very much extened in the bass and upper frequencies. I never found the deeper resonances shrunken and the disconnected from the upper harmonic focus & ping. Maybe it was my system. The only SS preamp that I thought bettered the X-1 was the Tom Evans Vibe, but that preamp better everything I have heard in my system to date ( and that sould be a ton of them). I am now using a Counterpoint SA-5000 since I had to downsize my system for financial reasons and recently compared it to the Rogue 99, Audible Illusions Modulus 3A, and Quicksilver preamps and the Counterpoint killed them by a long shot, the closest one was the 3A. The others were congested and not as real sounding especially on piano, vocals and naturalness.

My opinion, YMMV.

Happy Listening.
Hello, Lanny old friend. It sounds like you have been drinking a lot of really fine coffee. Whew! But as far as the preamp goes, I could not agree more. It is, so far, the best preamp I have ever used in my own home. It certainly does not have the lushness of tubes, but that is a subjective listening preference--like CJ Premier 11A amp on Quad ESL 63s, a gorgeous, gorgeous sound and lots of fun, but not exactly accurate. I personally think choosing a system that sounds the way YOU LIKE is quite allright. Listening to music should be fun and pleasurable. No home system sounds like music anyway. But if we are talking about neutrality, transparency, dynamics and all the rest, the Pass X1 is the best I have yet heard. It is audibly superior to the X2.5, which itself is a very good preamp.

Have fun, Lanny.

PS: But when are you finally going to get over dynamic speaker and buy an electrostatic. IMHO, Quads or Soundlabs will take you to a level that you never imagined.

I am not going to check spelling before I post this, so my apologies for any spelling mistakes.