March 2022

Pass Laboratories XP-22 Line Pre & XP-27 Phono Pre Review
Colossal soundstage and the pinpoint imagining prowess!
Review By Tom Lyle

  I began to assemble my first "real" audio system while still in high school. I made it chiefly from DIY components and other "vintage" gear I could scrounge from friends and family. At that time, I don't think I heard anyone use the term "audiophile." All I knew was that I wanted to hear music at home on a better system than the mass-market stuff sold at department stores.

This was also about the same time I discovered a high-end audio showroom near my parent's suburban home. Every once in a while, I would quietly enter their store. There was no way I would have been able to sit in the comfy chair in front of one of the active displays and listen to a system. But I did walk among the array of components on display, and when no one was looking, turn the knobs up and down and flip the switches on the front panels of a component or two while it was muted or its power was off.

At that age, there were plenty of activities that were more risqué than listening in on a customer's demo, let alone experiencing the sensation of the silky-smooth mechanisms of these high-end audio components' volume controls.

I had no idea that the smooth-running volume controls on those components were one of the reasons why this equipment sounded so good (and was so expensive). But I did have a sense that this was only one of the reasons why this audio equipment was priced so much higher than mass-market audio equipment. But even when hearing these systems off-axis as when I did when peering in on a demo, I did not doubt that the high-end audio systems they were selling at this audio salon sounded better than the mix and match system I was using in my parents' basement at the time.

Pass Laboratories XP-22 Line Preamplifier
The volume control on the Pass Laboratories XP-22 ($9975) reviewed here happens to have a silky-smooth running volume control, similar to the volume controls I covertly discovered so long ago. As I began to investigate the other features of the Pass Labs XP-22, both sonic and intangible, I learned that its volume control was a significant focus of Pass Laboratories' design upgrades that brought the XP-22 to fruition.

The XP-22's volume control is a single-stage design preamplifier that has many functions; the volume control is most often used as a volume attenuator. Ask anyone who has either accidentally (or purposely) connected a source component with no volume control directly to a power amplifier. If they didn't instantly blow their speakers, it still wasn't a pleasant experience.

Other improvements in design led to the birth of the Pass Labs XP-22, including a newly designed transformer. It's a double-shielded low noise toroidal transformer connected by aviation-grade circular connectors using silver over oxygen-free copper.

The XP-22's second chassis is a power supply that connects to the control unit via a heavy-duty umbilical. It is a dual-mono power supply that has two transformers. Two transformers lessen radiated and mechanical noise. On their website, I read that noise is the most prominent part of its total harmonic distortion specification (THD+N). The Pass design team lowered this noise and improved the preamp's resolution and dynamics.

The power supply used in the XP-22 line preamplifier is the same as what they used in their Xs preamplifier ($38k!). The larger output stage makes longer and multiple cable runs easier to drive and gives us the advantage of simplifying the XP-22's single-ended output circuitry while increasing performance.

The Pass Laboratories XP-22 measures very well, but at the same time, and most importantly, all of this makes it sound better.

Associated
I'll try to keep a discussion of the associated equipment used when auditioning the Pass Labs XP-22 preamplifier (and their XP27 phono preamplifier) as short as possible. Although, when I'm reading a review of a piece of high-end audio gear, I like reading about other audiophiles' systems. Skip this section if you wish. But as I believe the system in which a component is used is vital, this will give many a good idea of why the Pass Laboratories XP-22 preamplifier and the Pass Labs XP-27 performed admirably during their review period and beyond (spoiler alert!).

This digital front-end I used during the Pass Labs XP-22 audition period wasn't too shabby, primarily because of Ed Meitner's EMM Labs DA2 digital-to-analog converter. Connected to the DA2's USB input was a Wireworld Platinum Starlight USB cable. I connected the USB cable's other end to my computer-based music server. Although most files stored on the hard drives are CD-quality 16-bit / 44.1 files, I have a good collection of DSD files, many ripped for me by others who have the equipment to do so, and many that I purchased. The computer used for the music server is optimized for playing high-resolution DSD files. I could also pull up the Tidal and Qobuz websites to listen to high-resolution music files.

The music server's computer was also optimized for playback through its USB output. I also used an OPPO UDP-203 Blu-Ray/universal disc player/streamer when listening to physical SACDs, DVD-Audio discs. The analog output of the OPPO player was connected to an input on the Pass Labs XP-22 preamp using an unbalanced Kimber Carbon 8 interconnect; its digital output was connected to a coax input on the EMM DA2 using a 1.5-meter Accusound Digital Link cable.

I've been using the same analog front-end for quite a while, although that gear has seen some sonically significant modifications over time. The turntable was a Basis Audio Debut V, the tonearm a Tri-Planar 6. On its headshell was mounted a Top Wing Suzaku "Red Sparrow" low-output moving coil phono cartridge, which was lent to me by Believe HiFi for a review in our May 2020 issue. At first, the tonearm's hard-wired RCA cables delivered the output from the phono cartridge to the RCA inputs on the rear panel of what was my reference, a Pass Labs XP-17 phono preamplifier. Shortly after, by the second subject of this review, the Pass XP-27 phono preamplifier.

The remaining equipment in the review system consisted of a Pass Labs X250.8 power amplifier connected to a pair of Sound Lab Majestic 454 full-range electrostatic speakers using a 3-meter run of Kimber Carbon 18 XL speaker cables. Augmenting the deep bass of the Sound Labs (which claim to have a low-frequency response of 32 Hz) were a pair of SVS SB16 Ultras (which SVS says reaches down to 16 Hz).

I set up all this gear in an acoustically treated, medium-sized listening room with two dedicated AC lines. These AC lines run directly to the circuit panel in our basement. I connected the equipment's power cables into high-end "audiophile" cryogenically-treated duplex wall receptacles. Even though they were recommended to me, I'm not willing to claim whether or not these duplex outlets made a difference in sound quality or not. I didn't have the opportunity to compare them with the generic receptacles that came with our house, and I never will.

Accommodate
The XP-22 preamplifier can accommodate five sources via three unbalanced RCA inputs and two balanced XLR inputs. It has both balanced and unbalanced outputs. It seems as if tape loops are an endangered species on preamplifiers these days, but thankfully the XP-22 sports RCA inputs for both tape-in and tape-out.

In advertisements and other photos of the XP-22 preamplifier, it is always pictured with its two chassis stacked upon each other. The preamp's manual states that they can indeed be set up this way, but they discourage this, stating in its manual, "...for best performance they should be separated a little". And that's what I did, placing the preamp's control chassis on one shelf of my Arcici Suspense equipment rack and its power supply two shelves lower. In a future review, I will attempt to tackle the dilemma of print ads showing a handsome couple seated on a couch in a gorgeous living space listening to an entire high-end audio system with zero audio cables.

Audition
Throughout the audition period and beyond, the performance of the XP-22 was exemplary. As I would expect from a solid-state component designed and manufactured in the 2020s, I heard no clicks, buzzes, or hum coming through my speakers, and there was complete silence when it was powered and no program material coming through it.

My first listen to the 1963 album Duke Ellington and John Coltrane through the XP-22 was revelatory. From the early days until now, when listening to this album, the goal had always been to get closer to the music I was listening to. Whether I was spinning the Impulse Records LP or decoding the Japanese SACD file through the music server, the transparency of this Pass Labs preamplifier made it seem as if I had that direct connection to the original event that was recorded so long ago.

When I first purchased the LP version of this album, I had never heard it before. I had my doubts about whether or not I would like it. Even though I was very much into John Coltrane, I wasn't that much into big band jazz at the time. After my first listen, I felt like a fool for not checking it out earlier, although, in those pre-internet days, that wasn't as easy as it is today. To my surprise, this album sounded like a great John Coltrane album, with his longtime bandmates Elvin Jones on drums and Jimmy Garrison on bass, but with a stellar guest pianist named Duke Ellington replacing Coltrane's longtime bandmate McCoy Tyner.

Coltrane's style in 1963 was considered a turning point for many jazz fans. His playing style hadn't entered its free-jazz phase yet, but it was becoming more complex, often arising from a hyper-intelligent stream of consciousness that some found too challenging for some to follow. Not me, as I listened to John Coltrane for many years and loved all his published material. What was most surprising about this pairing was discovering how advanced Ellington's piano playing was and how well his playing fit on this extraordinary session.

Yes, in the above paragraph, I'm not directly describing the sound of the Pass Labs XP-22 preamplifier. I'm discussing the music on the Ellington/Coltrane album. This is what the XP-22 is all about. It archives near-total transparency, making it have barely any sonic personality of its own. It is futile to compare its transparency to the best solid-state preamplifiers or its vast soundstage and lustrous midrange to a tube preamp. The Pass Laboratories XP-22 preamplifier sounds like an excellent preamp, period.

The Ellington / Coltrane SACD album isn't a perfect recording. Some might be bothered because of the slight amount of tape hiss, as well as the hard-panning of Coltrane's sax to one speaker. This panning is why many prefer the mono version of this album. The SACD version made me feel that the hard-panning was a little less noticeable, maybe because I could hear more of the bleed coming through the other microphones more clearly, or I was distracted by the SACD's outstanding sound quality.

But I have zero complaints about the reproduction of this album when the signal passes through the Pass Labs XP-22. The feeling of being a fly on the wall at Rudy Van Gelder's studio has rarely been equaled. Plus, I often left the Pass' weighty metal remote out of reach, just so I could adjust this preamplifier's silken volume control by hand, reminding myself once more that with the Pass Laboratories XP-22 in my system, I have attained high-end audio equipment bliss.

Pass Laboratories XP-27 Phono Preamplifier
Like the XP-22-line preamplifier above, the XP-27 phono preamplifier ($12,075) is a two-chassis component. And like the XP-22, one of its chassis is the power supply, the other the control unit. As I did with the XP-22 preamp, I placed them two shelves away from each other on the Arcici Suspense equipment rack. This still allowed the umbilical that attaches the two to reach the rear panel of each component.

Besides the obvious benefit of improved sound quality over my reference Pass Labs XP-17 phono preamp, the control unit of the XP-27 had its loading and gain controls on its front panel. This was a significant upgrade.

Front panel controls on a phono preamplifier are invaluable, especially for those audiophiles who use multiple phono cartridges or multiple tonearms on their turntable. In the manual for the XP-27 phono preamp, Pass Labs wisely states that this phono preamp will enable those with two tonearms or two turntables can play or sample music from both can do so with a single XP-27, "this simplifying their complement of analog equipment and removing one variable from their listening chain".

Front panel controls are very convenient when installing a new phono cartridge, changing the loading settings while a record plays to find the optimum settings. I can't imagine any audiophile not appreciating the XP-27's ability to change this phono preamplifier's settings "on the fly," that is, while listening to a record.

There is also a mute switch on the front panel of the phono preamp (thank you very much) and a low pass filter switch. Back in the day, the low-pass filter on a phono preamp, or most likely a receiver, used to be called the "rumble filter." The reasons for this filter back then were many, including low-frequency feedback from less than stellar turntables. I doubt that the XP-27 would be used with less than a very decent turntable. Still, it might come in handy when playing irreplaceable older vinyl, which might be slightly warped, or those records that weren't recorded very well in the first place.

The front panel controls of the XP-27 allow for infinite choices of loading one's phono cartridge. There are three relatively large control knobs on the phono preamp's front panel. From left to right, there the resistance loading control gives one nine choices ranging from 30 to 47k Ohm, to its right is the capacitance (reactive) loading control, which has six settings, from 100 picofarads (pf.) to 750 pf., and farthest to right is the gain control. For moving magnet (MM) phono cartridges, there is the requisite 53 dB. There are two settings for moving coil (MC) phono cartridges, 66 dB or 76 dB. Moving iron usually requires a setting of 66 dB, and even though some listeners might find 76 dB a bit too much, it wouldn't surprise me if some have used that setting.

Those who are new to vinyl playback or in the past have relied on others to set their loading options and other setup details will appreciate the manual of the Pass XP-27, which goes into much detail (but not too much) about the subject of loading and gain settings. They even go as far as to include a short treatise on moving coil cartridge set up and the philosophy and exercise of how one might go about setting up one's phono stage. Although, they admit that the loading of moving coil cartridges is "at best a very inexact science, and that "specific requirements for loading moving coil devices should be taken (and offered) very lightly". I love these guys!

Replaces
The Pass Labs XP-27 replaces their XP-25 phono preamplifier, introduced in 2015. It seems as if as soon as the XP-25 was introduced, they began working on its replacement, the XP27, which was finally introduced last year.

I could explain the many technical improvements made to this phono preamplifier, but I think Wayne Colburn, Nelson Pass' design partner did a much better job. This is an excerpt and paraphrasing of an email in which Wayne gave his thoughts on the Pass Labs' XP-27 vs. the older XP-25. This email was pointed out to me by a longtime industry veteran and CEO of JB Stanton Communications, Bryan Stanton. JB Stanton is Pass Labs' sole N. American media representative. I've edited and paraphrased much of this email for this review:

"The XP-27 was upgraded from a single transformer in the XP-25 to custom-designed dual transformers. The new transformers are low noise, vacuum epoxy sealed, and have MU metal shields. The rectifiers have been upgraded to lower noise, suppress ringing, and lower electromagnetic interference (EMI). The power filtering has been improved in the XP-27, with added capacitance and pre-regulation."

"The cable (umbilical) that runs from the power supply to the amplifier is also new. It is heavier and is better shielded, with nicer connectors that Japan Aerospace makes. The input gain section uses newer low-noise resistors but uses the identical Toshiba low noise transistors. The gain settings are set differently than in the older XP-25. I varied the feedback to set the gain, but on the XP-27, an attenuator is now used. The sound quality can vary with feedback changes, so it is now more consistent with gain changes. The secondary gain section has a similar topology but is now DC-coupled and has upgraded parts and an improved circuit layout."

"The XP-25 was quite good, but these improvements add up to make the newer XP-27 even better."

 

I feel a bit hypocritical providing this technical information regarding the improvements made to this wonderful sounding component. I've said it so many times I feel as if some may be tired of me saying it – If a component sounds better than a similarly priced component, it matches well with the rest of a system, and it comes with a good warranty, I don't care if was made with parts of ballpoint pens and held together with duct tape.

Ears
I've also repeatedly said that the best measuring device is one's ears. As an audio reviewer, it is my job to describe my experience with the component in my system. As far as the Pass Laboratories XP-27 is concerned, I was impressed with it in every sonic area I can think of. This phono preamplifier greatly impressed me with the added benefit of front panel controls. I played dozens of records through the XP-27, but one that could likely sum up my feelings about it is the third Peter Gabriel solo LP.

It has never bothered me that the general public has admired Peter Gabriel's third self-titled album from 1980, often entitled Melt or Peter Gabriel 3. The first copy I bought as soon as it was released. Classic Records pressed my current copy, which I acquired as soon as it was released.

Wikipedia calls this album Peter Gabriel's "artistic breakthrough" and that it "established him as one of rock's most ambitious and innovative musicians." Others loathe Gabriel's embrace of the "gated snare" effect that he and producer Steve Lillywhite seemed to adore at the time. Peter Gabriel's albums have been in my collection since he released his first solo album because he was the lead singer of Genesis. I did not ask to see his CV. Perhaps I'm in love with this album because he opened with the song "Intruder" when I attended a show on the tour of this album at Asbury Park in 1980.

Regardless, the Pass Labs XP-27 didn't magically transform this album into a live-in-the-studio recording. Much of the music on this album is the musical equivalent of CGI, yet they had no internet or computers when recording this album. The creativity dripped from the turntable as if it were a half-used candle. The gated reverb on the drums on "Intruder" and "Biko" passed through my body not because the bass frequencies were powerful and infinitely deep, as they shook my gut and the window frames in my listening room. But I mostly mean that they went through me emotionally, as the music on this album disregarded the laws of physics, and my music brain followed suit. Yes, the midrange of the XP-27 was scarily transparent. Even though I've been listening to this album all my adult life, I would still lean forward in an attempt to hear every nanosecond of, for example, the reverb trail of Gabriel's voice on "Biko," the last track on the LP.

For this album, Peter Gabriel instructed drummers Phil Collins and Jerry Marotta not to use their cymbals on their drum kits. This left space for the treble energy of other instruments. On this cymbal-free album, the XP-27 reproduced the highs as if they were magical, regardless of the instrument, voice, or sound effect it was reproducing.

The treble sounds from every instrument and voice would fill the enormous soundstage with sparkling, reflected sound waves that sonically resembled embers rising from a campfire - the paths of the individual embers presumably random but in actuality determined by air currents.

Live
Later that evening, I spun the live Kraftwerk album Minimum Maximum. Finding this album on vinyl wasn't easy (or inexpensive), but I feel that this four-LP set was very much worth the effort. After the experience of playing side two of the third LP, which features tunes from Kraftwerk's 1981 Computer World album, I was convinced that the XP-27 could easily compete with the best $15,000 to $25,000 phono preamplifiers I've ever had in my system.

It was the XP-27's colossal soundstage and the pinpoint imagining prowess of this phono stage that filled the space between, behind, and to the sides of the Sound Lab Majestic 545 electrostatic monoliths. I felt enveloped by sound as Kraftwerk's music took up the front of my listening room. I attended two shows on this tour, sadly founding member Florian Schneider's last. The Pass Labs XP-27 phono preamp allowed me the pleasure of reliving these extraordinary concerts in my home.

The bass synthesizers on this album were reproduced with purity and tightness that I've only heard a few times since upgrading my system to having two subwoofers. It wasn't only the bass that had me convinced of this phono preamp's distinction. I could recite all the audiophile clichés and use them as tags for describing this phono preamp's perfectionist traits – it had a colossal soundstage filled with pinpoint images, its midrange was ultra-transparent, its transient response was as quick as I've ever heard, its microdynamics and macrodynamic capacity aided in rendering a lifelike portrayal of acoustic instruments and vocals, and the vast dynamic distance between instruments may make listeners wonder if this is a solid-state or tube-powered component.

Components
I realize it is not a contest, but the XP-27 had the upper hand between these two components. The XP-22-line preamplifier and XP-27 phono preamplifier are worth considering for one's system. They are both top-class high-end audio components. But the XP-27 phono preamp is the star of the two-component show. It blew me away. And I don't say that very often when it comes to any audio component.

But I would certainly recommend the Pass Laboratories XP-22 line preamplifier to anyone looking for a preamp anywhere near its price. In fact, compared to other preamps in its price range, this component should be considered a bargain. The features of the Pass Labs XP-22, both sonic and intangible, make me feel very comfortable recommending it to other audiophiles.

I'm convinced that one would have to spend much more on a phono preamplifier to equal the performance and ease of use of the Pass XP-27 phono preamplifier. Its sound quality in my system was unequaled, that is, unless I compare it to my experience with a phono preamplifier that I was lucky enough to have in my system that cost twice its price. Should I recommend the XP-27 to other vinyl-loving audiophiles? Is the sky blue?

Specifications
Type: High-end audio stereo preamplifier and MM / MC phono stage
Pass Laboratories XP-22 line preamplifier 
Gain: 9.6dB Balanced
Output Impedance: 25 Ohms RCA, 50 Ohms XLR
Input Impedance: 22 kOhms
Frequency Response: 10Hz to 20kHz (+/- 0.05 dB), -2dB @ 150 kHz
Crosstalk: > 100dB
Residual Noise: 2uV RMS
SNR: -125dB ref max out
THD: < 0.001 @ 1V 1kHz
Dimensions: 17" x 12.5" x 4" (WxDxH, two boxes)
Weight: 40 lbs.
Price: $9975

Pass Laboratories XP-27 phono preamplifier 
Gain Options: 56, 66, and 76dB
RIAA Response: 20 Hz to 20 kHz (+/-0.1dB)
Distortion: < 0.005 % THD @ 1mV MC input
< 0.002 % THD @ 10mV MM input
Maximum Output: 22 Volts rms.
Output Impedance: 150/150 Ohms
Input Impedance: 100pF to 750pF on any input 
30 Ohm to 47 kOhm any input
Unweighted Noise: -93 dB ref. 10 mV (MM), -85 dB ref. 1 mV (MC)
Dimensions: 17" x 12" x 4" (WxDxH, two chassis)
Weight: 45 lbs.
Price: $12,075

Company Information
Pass Laboratories
13395 New Airport Road
Suite G
Auburn, CA 95602

Voice: (530) 878-5350
E-mail: info@passlabs.com 
Website: PassLabs.com