Review: Liberty Audio B2B-1 Preamplifier


Category: Preamps

Liberty Audio B2B-1 Phono Preamp Review

Discalimer: I am not affiliated with Peter Noerbaek, Liberty Audio nor PBN Audio in any way and Peter and I have spoken by phone only once.

Some members of Audiogon that have followed various equipment threads I’ve contributed to through the years will know that, occasionally, I speak as a proponent of component evaluations that are optimally performed in the context of a system, and not in isolation. Isolated components, on their own, don’t have the ability to reproduce music; even headphones plugged into a CD player is a system of at least two separate components. OK, one can always argue that a boom box is a system. So be it. But this idea is nothing new, and perhaps I am a “disciple” of the many talented HiFi/Stereo professor-designer-implementers of yore, but I raise the issue to simply underscore that, in my personal experience, I have found that some components can thrive and excite in certain system contexts, while in others, the results may be mediocre or uninspiring at best. So, if you will, hold that thought while I try to set some of the additional “stage props” for this review of Peter Noerbaek’s fine Liberty Audio B2B-1 Phono Preamp (B2B) that I have spent the last month listening to and evaluating in the context of both solid state and tubed systems, as I will describe below.

Another element I’d like to recall for this review is the term Stereo, which from the Greek, means “a solid body or figure” or “three dimensions.” So bear with me on this last point in concert with the idea of “system context” because, as I’ve listened carefully to the B2B using a wide variety of original, well cared for, and new, vinyl pressings, I’ve tried to focus on those sonic elements that bring about a “solid aural view” of the music, and what characteristics of the coherence of soundstage, ambience, dynamics and frequency response that bring forth a pleasurable and immersive “forget-the-components and system” listening experience.

Because it would be too easy to simply compare the B2B to phono stages I’ve owned in the past (Krell KPE Reference, Aesthetix Rhea, EAR 834P, Parasound PP-1, Bryston BP25 phono section) or auditioned in my systems (Audio Research PH5, Musical Fidelity X-LP, Parasound JC-3), or to my current “reference” Manley Chinook phono pre, I have tried to evaluate the B2B simply on its own merits-in-system, as well as the comparative swapping in and out with the Chinook, in both systems, both by myself and with audio (vinyloholic!) friends, whose ears and listening abilities I trust.

I noticed that over the past year or so, in some Audiogon threads, discussing the merits or attributes of various phono preamps, and members helping one another with ideas about which might be a good phono pre candidate for a fellow enthusiast, Peter would once in a while jump in with a recommendation about his Liberty phono pre. One fellow member recently asked appropriately, “has anyone actually heard this?”, which, on a spur of the moment, prompted me to write to Peter and ask for a loaner that I would be happy to evaluate and write a review about for Audiogon. Peter was kind enough to reply and take me up on the offer and he shipped a new unit to me a week later; below are my thoughts about this component, auditioned in the comfort of my home, with both solid state and tubed systems.

About twelve years ago I started building piece by piece what has become my current solid state system: VPI Aries2/JMW 10.5 arm/Lyra Helikon and Delos cartridges, Krell KCT preamp/400cx amp, and Thiel CS6 speakers. Originally, I had Krell’s KPE Reference phono pre in the system as well, and after a few years of enjoying that phono stage and learning the ins and outs of various loading settings on different moving coil cartridges, felt that perhaps a tubed stage would be best to soften the sometimes “minor midrange glare” or “shoutiness” I would sometimes hear on a few not-so-well-produced-but-music-I-like recordings. So, for the next eight years, it would only tubed stages I would consider and enjoy in this system, all the while the Krells and Thiels continued to break in, and the occasional “shout” problem was pretty much gone whether by the tubes, the components settling, ot a combination of both. My second system began with a small inexperienced interest in tubes for a modest “bedroom system” a few years ago that has now “grown” into a full blown, second system for another listening area. This is a Manley tube based system with VPI Traveler/Lyra Delos, Chinook phono pre, Jumbo Shrimp preamp and Snapper monoblocks driving Thiel CS2.4s.

Unpacking and installing the B2B was a pleasure; it is very well built and is substantially heavier than the Chinook given the extra iron in the form of not one but two power transformers, one for each channel. You can read the description, features and specs of the circuitry in Peter’s white paper and Liberty audio website; suffice it to say the unit is very well constructed, and though I did not pull off the main cover, I did pull the small panel on top to verify the proper MC and load settings via the B2B’s jumper options; the build and component quality are top notch and it certainly looks like every effort was made to produce a robust and long lasting preamp. Peter explained his use of Toshiba JFETs, which as I recall, were what John Curl used in his famous phono stage long ago. The results are well worth listening to and sharing.

I have always been a fan of rock, jazz and classical and the albums I used for this audition ranged from Steely Dan’s “Babylon Sister“ from Gaucho, Jeff Beck Group’s 1972 “I’m Goin’ Down,” Donovan’s “Hurdy Gurdy Man” from his “Best Of” compilation, Count Basie’s “Chairman of the Board“ on the reissue Classic Records, Dream Theatre’s “A Dramatic Turn of Events,” Dead Can Dance’ “Anastasis” and my clean, original copy of the Pixies’ “Doolittle” that I bought in Boston the day it came out in 1989.

My preference in listening is to hear music that is reproduced in a coherent and believable soundstage. If a system quickly makes me forget I am listening-to-a-system, then I am happy. I enjoy hearing an even frequency response with excellent dynamics and phase coherence, but also, those low level ambient details that make the music “believably played by people,” i.e., the feeling that people are standing in front of me actually playing music in four dimensions; three of space and one of time. I should know how this sounds; I am also a musician/composer/producer (guitar, bass, keyboards) and have played and recorded in bands professionally.

Right out of the gate, the B2B excels in very low level ambient retrieval due to its extremely low noise floor. I can confidently state that it is, by far, the quietest phono preamp I have ever had in my systems and with the Krell/Thiel set up in particular, this greatly contributed to a room-disappearing hall-like surround sound that had superb height and width of stage. An analog phono preamp can’t synthesize information that isn’t already there, but it could phase cancel ambient information with added noise. The low level information that is revealed by the B2B with its excellent signal to noise, along with a soundstage coherence that never lets chaotic or heavily congested tracks like the Pixies’ “Crackity Jones” or Dream Theatre’s “Breaking All Illusions” get away in a smear, lets all the musical detail remain intact, across the audible frequency range and in a proper spacial context, with a pleasant tunefulness that attests to its superb design and execution. At first I thought the midrange was somewhat reticent when compared to the Chinook, but upon further comparison and confirmation by my audio buds, these are really two different flavors of the mids. With the B2B, the midrange, which is often the hardest part of the range to reproduce accurately, falls into its own space within the greater whole, and beckons deeper attention to detail. It never shouts out inappropriately, and even the blatty, strident trumpet on Count Basie held its own timbre evenly and full bodied. Leading edges of vocals and piano, two of the most difficult instruments to reproduce well, sounded very natural; the overall mids reproduced by the B2B drew my ears toward the whole musical event without any highlighted “pinpointing” of any particular detail. This is not to say the B2B is without great dynamics; on the contrary, it punches as well as any phono stage I have had previously in my system, and begs one to crank the volume. It is just so easy on the ears in the midrange that at first I wondered if it suffered dynamically compared to the Manley (or any other phono pre I have listened to). It doesn’t.

Highs seem a little “relaxed” relative to the Manley, but to test this, when listening to the tinkly chimes on “Babylon Sister” right after the line, “…here come those Santa Ana winds again…” and then the musical phrase ends a couple of measures later with these low-level percussive, one can hear this detail equally as well with either stage. Heavy cymbal work from Count Basie, with brushes and snare, are all naturally reproduced and kick drum on every album I threw at it was tuneful, full and punched the air such that I felt the power and air movement. The attack of drumsticks on heads and the beater on the kick was also well enveloped, with appropriate attack, sustain, decay and release. Bass extension and texture on the synthesized Anastasis shook my room and the bass pedals from Dream Theatre compelled me to utter a few “wows.”

If there were any characterstics that the Chinook may have “bested” the B2B, it was in the area of the bass. The Manley provides a highly textured quality to bass notes that were somewhat smoothed out by the B2B, even though both preamps delivered a true bass note, no matter how low. There were times, especially on the Count Basie recording, where I preferred the attack of the plucked string on the Manley; it seemed a bit quicker and the transient sounded more a part of the note immediately in the aftermath of the event, with the texture bloom more of a coherent part of the pluck. Don’t get me wrong, the B2B did fine job of this as well, perhaps 90% of it, it just that the tubed phono pre seemed to have a hold on that one particular aspect over the solid state preamp. In the area of quickness, the B2B outpaced the Manley, but transistors should slew more quickly than thermionic devices.

Evenness of coherence of soundstage, extremely high signal to noise and detail are the strengths of this pre amp; some inter-track sections on very quiet vinyl were so low in noise that it was scarily like CD and I often noted that. Let me say it again, this phono pre is QUIET. The Manley has some low level tube hum, this is normal for such a design, albeit it is one of the quietest of tubed phono stages I have owned.

In the all tube system, the B2B didn’t perform as well and it could very well be that the design factor by the highly talented Mitch Margolis, who designed several of Manley’s home audio circuits, allows the Chinook, Jumbo Shrimp and Snappers to all work together in an impedance- coupled and optimized configuration. The B2B sounded good in this system, but it lacked the warmth and musical magic and coherence afforded by the Chinook in this context. With only tubes powering the analog playback, one quickly forgets they are listening to a system, a point that was suggested by my audio buddies. With the B2B in place, one “gets there” eventually, but the arrival at that “no system in place” is not as immediate as with the all Manley set up. With the tubes downstream, the dynamics seemed a little less forthcoming, especially in the midrange, and several comments about this made it worth mentioning. In the solid state system this midrange reticence was not noticeable; instead the smoothness and evenness of detail that caused ears to relax and take all the music in, no matter the volume level, was greatly appreciated.

In the end, this is a superb phono preamp that is extremely quiet (I said it again) and musical, with top to bottom coherence and an enveloping wide and deep soundstage, all of which I believe is the result of excellent low level information retrieval afforded by outstanding signal-to-noise and separation specifications. Regardless of its price ($1749 direct) it should be highly competitive with any phono pre in the $2000 to $3000 range, which is highly populated with some of the most popular offerings out there. To all those Audiogon enthusiasts that want to know if this phono preamp is any good, I wholeheartedly say, heck yeah!, So how much did I like it? It’s not going back; enough to purchase the unit Peter sent to me and it has found a home in my Krell/Thiel system. My audio buds also agree with me this is the way to go. Perhaps it’s the way solid state components work with each other from an integration or output/input impedance optimal-matching point of view, whatever the case, I know it sounds better than any phono preamp I’ve had in that system before, and I spent the day today listening again and again as I was putting the final touches to this review to try and find any more shortcomings of this fine phono preamp. So far, I can’t, and it sounds better the more it breaks in, going on a month now of almost daily listening. If anyone has questions please do not hesitate to write to me.

Do yourself, and your ears, a huge favor and check this phono stage out; I’d be interested to hear from other owners. Especially with solid state systems, those Toshiba JFETs are electronic works of art in a state-of-the-art-affordable-price-point configuration (ah all these noun trains you say!).

I am confident the B2B will bring a smile to your face and an “ahhhhh” to your lips, as it has already done to mine and my audio friends many times. And you will find yourself turning up the volume to hear a bit more of just what this outstanding phono preamp delivers.

Steve Chamberlain
April 2013

Associated gear
VPI Aries and Traveler turntables
Lyra Helikon and Delos cartridges
Krell/Manley electronics
Thiel speakers

Similar products
Manley Chinook
Aesthetix Rhea
EAR 834P
Krell KPE reference
stevecham
I bought 4 NOS Philips JAN tubes for the Chinook from Tube Depot and this has made all the difference in improved sound quality and stability.
Thanks for the recommendation!I went to the Tube Depot site to order the tubes but I don't know what catalog number you ordered.Last night I put on a record and in less than five minutes I got a loud hum from my speakers followed by a loud pop.Do you think this might be caused by defective tubes or could it be another capacitor issue?
I just hooked up my B2B on Monday this week and am extremely pleased with the sound. I'd like to add to the review a bit from my own perspective.

As I'm sure that many people realize, a phono stage has two difficult tasks. One is to increase the voltage of the signal from (in my case) a MC signal of merely 0.3 millivolts to a line signal of 5 volts- that's over 10,000 fold, and it must do it with as little error as possible. The other function is to equalize the signal. When cutting the laquer from the tape master, RIAA standards mandate a curve that sets the 1kHz area as 0 db, with maked compression below that (-20 db at 20 Hz) and marked expansion above (+20 db at 20 kHz). This is necessary to fit the signal within the grooves (low frequencies) and reduce the noise at higher frequencies. In my experience, phono stages fall short of faithfully following this curve, particularly at the low end. Remarkably, the B2B is extremely precise in following these standards.

The B2B accomplishes this feat by Class A design with FET components. It is huge compared with my NAD PP-3. Peter showed me the circuit boards and the unit is heavily shielded to avoid RFI. It just reeks of quality, both in design, component selection, and assembly. I had tried the PP-3 with the MC input but found the sound shrill and distinctly lacking in bass. Later I added an SUT and hooked it up to the MM input, with great increase in bass. Still, I thought that I could do better as some of my collection of SACD's did sound better than the vinyl versions, so in came the B2B.

I can say now that the bass is as rich and powerful as one could ever want. Also, there is a noticible reduction in the background noise of the vinyl, and the small hum that my SUT produced was gone. My vinyl is not only superior to CD in frequency response, it has a greater soundstage particularly in the z axis. Were it not for the occasional pop in some records I couldn't tell it from an SACD recording.

For reference, I am using a Pro-Ject 5.1 with Audio-Technica AT-33e cartridge, MingDa APS 300 tube preamp using 300B's, McCormack DNA-250 SS amp, and Ohm 5000 speakers. I set the B2B for 100 ohms, MC for an exact match to the needle (this is the default out of the box).
How would you compare the Liberty to the Aesthetix Rhea in a all tube system. I am interested in both. How does it compare in stage, back to front, overall sound and detail. Which one is leaner? Thank You.
Hi, are you still using the B2B1? I am researching phono stages for a future change, the JC3+ was on my list, how does the Liberty compare? I was also considering the Lehmann Decade and Sutherland 20/20, I was wanting something quiet & quick still allowing the melody or musicality to come through.