- Category: Full-Length Reviews
- Created on Thursday, 01 December 2011 00:00
- Written by Uday Reddy
Buy an audio component and you buy its designer’s vision. Buy a loudspeaker, amplifier, or turntable from PBN Audio, and it’s Peter Noerbaek’s vision you’ve brought home. PBN’s success is a testament to the power of his vision, and proof that the entrepreneurial spirit is alive and well in high-end audio.
Founded by Noerbaek as a part-time business in 1992 and full-time since 1993, PBN Audio took a while to gestate. Although trained as an electrical engineer in his native Denmark, in 1986 Noerbaek was transferred by his company to their office in San Diego; apart from a brief interval, he’s been there ever since.
Noerbaek had built loudspeakers since he was a kid. To promote the models he was now designing, he teamed up with Cary Audio’s Dennis Had at the 1993 Consumer Electronics Show, and eventually moved to North Carolina to become Cary’s sales manager. But Noerbaek and his family missed the West Coast, and within ten months were back in San Diego.
Since 1995 PBN Audio has steadily grown, expanding their product line and their facilities -- from Noerbaek’s garage, to a factory in an industrial park that they soon outgrew, to, in 2004, their current facility in El Cajon, California. There everything is done under one roof, from CNC cabinet construction to final assembly and finishing.
As more and more high-end-audio equipment is designed in North America, the UK, or Europe but manufactured in China, it’s nice to see components designed and built here in the USA, especially in the notoriously business-unfriendly state of California by an immigrant from Europe.
The Montana Liberty ($15,000 USD per pair) is part of PBN’s InnerChoic line of speakers, which includes the Montana Lucy and the Montana Sammy, the latter reviewed by Jeff Fritz in Ultra Audio in October 2010.
Named after Noerbaek’s nine-year-old daughter, the Liberty is a three-way ported loudspeaker with four drivers: a 1” gold-plated titanium-neodymium Audax tweeter, a 6” coated reed-fiber SB Acoustics midrange, and two 8” black-anodized aluminum SEAS woofers. The crossover frequencies are 220 and 2100Hz. The claimed frequency response is generous: 23Hz-30kHz, ±3dB. With a voltage sensitivity of 90dB and a nominal impedance of 4 ohms (2.5 ohms minimum, 8 ohms maximum), the Liberty should be able to be driven easily by most amplifiers, including low-powered tube designs.
Although at 180 pounds the Liberty is similar in weight to my first-generation Wilson Audio Sophias ($11,700/pair when available), at 43”H x 14”W x 17”D it’s both wider and taller, though about the same depth. Despite their weight, the Libertys didn’t visually dominate my room. While not the most beautiful speaker to look at, the Libertys look purposeful, and are available in a number of colors and real-wood veneers. The review samples were finished in Gloss Piano Black. The finish wasn’t spectacular, à la Wilson, but it was well done, even though the samples had some rough edges in less conspicuous areas. (The pair on display at the T.H.E. Show in Newport Beach last June had a far superior wood finish.) Noerbaek maintains that he’s far more interested in making a speaker beautiful on the inside.
Speaking of the Liberty’s innards, its cabinet comprises stacked layers of MDF Ranger Board, CNC-cut with inner ribs and integral cross braces to reinforce the cabinet’s rigidity and help eliminate standing waves within it. The baffle the drive-units are mounted on is made of a 1.625”-thick section of hardwood. Rapping my knuckles on the baffle, top panel, and sides of the cabinet produced solid, satisfying thunks.
Near the bottom of the rear panel are two gold-plated binding posts that accept bare wire, spade lugs, and banana plugs. Like my Wilson Sophias, the Libertys can be single-wired only. Integral to the MDF base of each speaker is the forward-firing port, plus outrigger feet of 6061-grade aluminum. These supports differ from all others I’ve seen; usually, spikes are screwed into outriggers from below, an installation that requires resting the speaker on its side or performing a precarious balancing act. The Liberty’s spikes are screwed in from above, the job eased by the inclusion of knurled plastic knobs -- a welcome change from the usual.
The Montana InnerChoic Libertys were delivered in person by Peter Noerbaek, who drove them from San Diego. The speakers are normally delivered in shipping crates; Noerbaek had instead had the speakers specially wrapped in protective foam, then laid flat on the bed of his Chevy Silverado. Now, that’s confidence in your build quality!
Ostensibly, Noerbaek had come along to set up the speakers himself. However, once he’d lugged them into my room, unwrapped them, and walked each speaker into an approximate position, he suggested I listen to some music while fine-tuning those positions as I wished. I thought this odd. Why drive a pair of speakers 90 minutes through Southern California traffic just to have me set them up? Anyway, I was game, so I put on In Session, by Albert King and Stevie Ray Vaughn (24/96 AIFF, Stax/HDtracks), and proceeded to maneuver the speakers into position. I soon realized that Noerbaek was so confident of the Liberty’s flexibility that he knew I’d have no trouble, and he was right. Despite their large size, I had them set up in less than ten minutes. In fact, the Liberty is probably easier to set up than any other speaker I’ve used. The pair of them ended up about 2” closer to the front wall and 6” closer to the sidewalls than my Sophias. Noerbaek locked them in place with their carpet-piercing spikes, and the Libertys were good to go.
Construction of the review pair had been completed at the end of the previous week, after which they’d undergone 60 hours of run-in at the PBN factory. That break-in time proved sufficient; I noticed no change in the speakers’ sound once they were up and running in my room. These units were so new that the smell of the newly applied lacquer was strong, even just outside my listening room; thankfully, this dissipated within a week.
Before he left, I asked Noerbaek if he wanted to caution me about anything regarding the Libertys. “Play them as loud as you like,” he said; “they can handle anything that you can throw at them.”
Which was the exact opposite of what I actually did, at first. In fact, for the first few weeks, I listened to music well below my usual volumes, and at nowhere near anything approaching realistic volumes. I’m happy to report that I didn’t miss much at all. The Libertys were so sensitive that little amplifier power was needed to get them to open up; even with large-scale orchestral works there was hardly any loss of scale, impact, or drama. Given a little more juice, the Libertys really sang, with a broad, deep soundstage and solid, three-dimensional imaging, despite their substantial bulk and height -- though taller than my reference Wilson Sophias, images through the Libertys remained realistically proportioned, not larger than life. And even at high SPLs, I never heard any chuffing from the front-firing ports.
My strongest first impression of the Montana Liberty was that it was incredibly resolving -- almost ruthlessly revealing of the source material. Good or bad, if something was on the recording, I heard it. This included incidental sounds such as musicians turning the pages of their music, audience noises in live recordings, even amplifier hum. While this wasn’t the first time I’d noticed these sounds, they were more apparent through the Liberty than through other speakers I’ve heard. Even more astonishing was hearing tape-edit points in some recordings that I hadn’t before noted. While this never took away from the music, it could be distracting at times, and a reminder of the artifice that high-end audio seeks, above all, to eliminate. But in the absence of such sonic cues, the Libertys offered much to love from top to bottom.
Whether in a preamp, a power amp, or a DAC, I have an inherent wariness of increased complexity in audio components, and especially in loudspeakers. The more drivers I see, the more I think of the possible trade-offs of crossover complexity and driver-output integration. With the PBNs I need not have worried: the Liberty was extremely coherent, each driver seamlessly handing off to the next to project the music as a uniform whole, not a mishmash of differing frequencies and instruments. In the rhythmically complex “Raju,” from Chick Corea and John McLaughlin’s Five Peace Band Live (16/44.1 AIFF, Concord), the weight and impact of Christian McBride’s electric bass and Vinnie Colaiuta’s drums retained all their forcefulness without interfering with the interplay of Corea’s electric piano with McLaughlin’s electric guitar.
I also found the Liberty quick and energetic, ready to turn on a dime with regard to transient response. In fact, the PBNs sounded more like electrostatics than any other dynamic speaker I’ve heard -- another testament to their overall coherence.
Given the Libertys’ greater low-frequency extension as compared to my Wilson Sophias, I was initially concerned that they’d overload my room. They didn’t. Dean Peer’s solo electric bass on his album Ucross (16/44.1 AIFF, Restless) was smooth, powerful, and tuneful, with solid weight and impact. Even when I pushed the Libertys hard, I heard no congestion or bass bloat. If you listen to a lot of bass-heavy music, you won’t be disappointed. Just for kicks, I cued up the launch sequence from Apollo 13, streamed from Netflix; the roar of the engines really shook the room.
However, this characteristic was not just about the Liberty’s low-bass extension in its reproduction of any particular instrument, or in the shaking of walls or windows. What this extension delivered, in addition to the low bass, was the added pressurization of my room, which helped to better reveal the recording venue’s acoustic dimensions. This characteristic was particularly noticeable with recordings of orchestral works and of solo acoustic piano, such as Keith Jarrett’s classic The Köln Concert (24/96 AIFF, ECM/HDtracks), recorded at the Cologne (Köln) Opera House in 1975. The echoes in the hall and the decay in the sustained notes were so well conveyed by the Libertys’ reproduction of low-frequency bass that I could almost suspend disbelief and imagine myself seated in the orchestra section.
Given the clarity described above, it came as no surprise to hear that the midrange was somewhat leaner than I’m used to hearing from my system. However, it by no means sounded cold or sterile, and the resulting further increase in clarity contributed to a high level of detail and sonic texture that I could appreciate with every recording, especially of orchestral works. Percy Grainger’s The Warriors (16/44.1 AIFF, Deutsche Grammophon), as performed by John Eliot Gardiner and the Philharmonia Orchestra, is very lively and kinetic; despite the Liberty’s leanness when compared to my reference speakers, the PBNs still conveyed this music’s essential rhythm, flow, and momentum.
In the treble the Liberty was beyond reproach, with a light, sweet, airy top end and no hardness, edge, or glare. Especially notable was the way the titanium tweeter handled cymbals and chimes: with a bright, ringing tone, delivering the essence of the percussive attack. Even with the tweeter well above the level of my ears when I sat down to listen, there was excellent dispersion; even listening off the tweeter axis was very enjoyable.
Besides the obvious difference of the added low-frequency extension, the Liberty’s bass quality was notably tighter than the Sophia’s, which sounded slightly less distinct and more woolly in that region. The Sophia seemed less airy and delicate in the treble, due largely, I would think, to a restriction in upper-frequency extension, but this wasn’t as much of an issue for me.
However, the most notable difference between the speakers was in the midrange, and I’m not quite sure what was responsible for this. In my system, the Liberty was clearly superior in clarity of reproduction, the Sophia sounding much warmer and less transparent. But in the last year I’ve reviewed two integrated amplifiers, the ASR Emitter I and the Music Culture Elegance MC 701, each of which enjoyed perfect synergy with the Sophia, making possible the kind of clarity I experienced with the pairing of my Jeff Rowland Design Group Concentra integrated and the Liberty. Was this just a matter of a more suitable pairing, or was it because the Liberty’s midrange was so uncolored? I’d like to think it was a little bit of both, but given the overall performance of these speakers, I lean toward the greater contribution to the overall sound being made by the PBN Liberty.
I haven’t heard Wilson’s latest version of the Sophia, but it costs only $1700/pair more than the Liberty, and $5000/pair more than my first-generation Sophias. The Sophia has some serious competition from the Montana Liberty.
The PBN Montana InnerChoic Liberty packs a lot of punch at the price: In short, it’s a great value. It’s not the most beautiful speaker in the world, but, like the plain Jane who asks you to dance, that complex cabinet hides a lot of inner beauty. In this case, the result is the striking outer beauty of your music. And that’s what matters most.
. . . Uday Reddy
- Speakers -- Wilson Audio Specialties Sophia
- Integrated amplifier -- Jeff Rowland Design Group Concentra
- Digital sources -- Logitech Transporter music server; Apple iMac OS 10.6.4, iTunes, Amarra 2.2; Devilsound USB DAC
- Interconnects -- Cardas Audio Neutral Reference, Halide Design S/PDIF asynchronous USB Bridge with BNC termination
- Speaker cables -- Cardas Audio Neutral Reference
- Headphones -- Sennheiser HD600 (with Cardas headphone cable upgrade), Ultimate Ears UE 11 Pro, Ray Samuels Audio Emmeline The Predator headphone amplifier
- Accessories -- Audio Power Industries Power Pack II power conditioner; Cardas Twinlink and Cardas Cross power cords; Cardas Audio Signature XLR, RCA, and BNC caps
PBN Audio Montana Liberty Loudspeakers
Price: $15,000 USD per pair.
Warranty: Five years parts and labor.
380 Vernon Way, Suites I & J
El Cajon, CA 92020
Phone: (619) 440-8237
Fax: (619) 579-6451