Note: Measurements taken in the anechoic chamber at Canada's National Research Council can be found through this link.
The pursuit of perfection is a lonely endeavor, and talent, on its own, doesn’t guarantee success. That talent must be nurtured and honed through years of practice and adversity, to fortify the constitution and single-mindedness required to create something of true excellence. Paul Barton founded PSB Speakers in 1972, and by 1974 had set to work in the anechoic chamber of Canada’s National Research Council (NRC) with Dr. Floyd E. Toole, one of the early pioneers of measurement-based loudspeaker design. Barton has worked vigilantly in the NRC ever since, having reviewed, by his own estimate, hundreds of thousands of measurements, all in the quest of slowly but surely improving his designs. He is, for me, firmly fixed in the pantheon of great loudspeaker designers.
The Alphas have been PSB’s most affordable line of loudspeakers, and a keystone of Barton’s product line, since 1991. Its replacement series, Alpha B, was launched in 1999 and remained in production through 2018. But Barton is particularly proud of his brand-new line of Alphas, the third generation. Running four models deep and available in vinyl finishes of Black Ash or American Walnut, the new line comprises the P3 ($199 USD/pair) and P5 ($349/pair) bookshelf models, the T20 tower ($599/pair), and the C10 center speaker ($299). Adjusting for inflation, the newest Alpha models are actually less expensive than the models they replace.
The newest Alphas, all two-way bass-reflex designs, are new from the ground up. Unlike the outgoing versions, which shared the same fundamental woofer design across the line’s various models, each of the new Alphas has a bespoke midrange-woofer tailored to that model, allowing Barton to coax every ounce of performance from his newest creations. The P3 has a 4” polypropylene midrange-woofer, the larger P5 a 5.25” variant of the same design, and the T20 and C10 each have two 5.25” woofers. Unlike your average polypropylene diaphragm, the new Alpha woofers are textured using an embossing technique that not only looks nice, almost like woven carbon fiber, but whose combination of thinness and stiffness helps increase the sensitivity by about 1dB. Also all new is PSB’s 0.75” tweeter of black anodized aluminum, used in every new Alpha model. This tweeter has a neodymium magnet and is cooled with ferrofluid; a waveguide helps optimize its performance on and off axis, and aligns characteristics of its dispersion with that of the midrange-woofer(s).
The P5 measures 11.4”H x 6.8”W x 9.5”D, weighs 10.2 pounds, and is made in China. My review samples had already made a pit stop with another reviewer and arrived a little worse for wear, with rub marks on one cabinet’s Black Ash finish. Still, I was struck by how attractive this minimonitor is. Its 1/2”-thick MDF cabinet was seamless, with rounded edges that give a softer, more modern look than previous Alphas, and that Black Ash finish was pretty nice. The drivers, mounted flush with the cabinet’s front baffle, display no mounting hardware -- rare for $349/pair. The 1”-thick front baffle seems to float, thanks to a small notch that lines the side of the cabinet. A thin silver ring around each driver lends this budget speaker a subtle flash of bougie class. Even the magnetically attached grilles, made of metal rather than the more common fabric, look upscale. Gold-plated five-way binding posts, a 2” bass-reflex port, and a 1/4” threaded insert on the cabinet’s rear, for mounting, round out the cabinet’s exterior. Inside, the cabinet is reasonably well-braced, with a wad of 1/2”-thick, felt-like damping material directly behind each driver. Barton argues that placing this material in the middle of the cabinet maximizes the conversion of sound energy to heat -- unlike the generic white fluff so many manufacturers have used.
The P5’s tweeter hands off to its midrange-woofer at 2.5kHz, and unusually for a high-end speaker -- though not for those designed by Paul Barton -- in the P3 and P5 the tweeter is below the woofer. Due to the fourth-order (24dB/octave) Linkwitz-Riley crossover network used in these models, the tweeter’s in-phase lobe naturally tilts up toward the woofer by about 15°, allowing the drive-units to remain in phase with each other from the height of the listener’s ears above the floor when seated (about 36”) to when that listener is standing, thus maximizing the speaker’s vertical sweet spot and overall stereo imaging.
PSB publishes more specifications than most speaker manufacturers, many of which charge far more for their products. The P5 has on-axis, anechoic frequency responses of 55Hz-21kHz, ±3dB, and 65Hz-20kHz, ±1.5dB. The 30° off-axis, anechoic response is 65Hz-10kHz, ±3dB, and the low-frequency cutoff is 37Hz, -10dB. Given that these are anechoic and not in-room measurements -- the latter are usually more generous -- this bodes well for the P5’s LF extension. The specified sensitivity is 87dB anechoic, 89dB in-room, while the nominal impedance is 8 ohms, with a 4-ohm minimum -- all of which suggest that this minimonitor should be an easy load for most amplifiers. PSB recommends partnering the P5s with an amplifier that can produce 10-90Wpc.
I perched the Alpha P5s atop generic 24”-high speaker stands about 8’ apart, 8.5’ from my listening position, and 16” from the front wall. The P5s were anything but fussy to set up; I toed them in until I could just see the inside of each speaker’s cabinet, and didn’t feel compelled to mess with them again. Using AudioQuest Rocket 33 speaker cables, I connected them to my Hegel Music Systems H590 integrated amplifier-DAC. Because even I admit that driving a $349 pair of speakers with an $11,000 amp is a bit daft, I also partnered the PSBs with NAD’s D 3045 integrated-DAC ($699). And to stream music from Qobuz Studio and Tidal HiFi, I connected each amp to my Intel NUC-based Roon Core music server with a DH Labs Silversonic USB link.
I’m not one for hyperbole -- my sober reviewing style has earned me the nickname “Eeyore” from one senior member of the SoundStage! staff -- but every once in a while I encounter a product for which I can shed my anhedonia and raincloud-like demeanor and, for a fleeting moment, once again feel feelings.
PSB’s Alpha P5 is sensational. This minimonitor looks good, but the quality of sound I found it capable of producing was nothing short of astonishing. If the P5’s sound has a defining characteristic, it’s its incredibly balanced linearity. “Neutral” speakers are often accused of sounding boring, and that makes sense, doesn’t it? A ruler-flat frequency response means that the speaker is not over- or underemphasizing anything. To my ears, Paul Barton has managed to pull off quite a trick with the P5: a speaker that is engaging to listen to and whose sound remains perfectly balanced. The fact that he’s done this in a speaker that he sells for $349/pair is remarkable.
Adele’s smash hit “Hello,” from her album 25 (16-bit/44.1kHz FLAC, XL/Tidal), highlighted all that was right about the Alpha P5. I’ve often written that the measure of a budget speaker isn’t so much what it gets right but what it doesn’t get wrong. When I hit Play and cranked the volume, Adele’s voice emerged from the center of the soundstage with startling clarity, specificity, and texture. I marveled at the fact that the P5s got everything right. Stereo imaging was excellent for this price and beyond, with zero ambiguity, and a stable central image even when I leaned to left or right of the speaker’s sweet spot, suggesting strong off-axis performance.
More impressive was the sheer amount of detail reproduced. Nine months ago, when I played the same track through Paradigm’s Monitor SE Atoms ($299/pair), Adele’s voice had a similarly neutral tonal quality, but sounded flatter and more veiled. Through the PSBs, I heard more: more microdetail, more body, more urgency, and, most important for this singer, more power. The P5s’ reproduction of “Hello” left me wanting nothing other than to play the song again and again; the Atoms left me a bit cold. That all-important emotional component of hi-fi was something that the Paradigms, for all their talents -- and we did bestow on them a Reviewers’ Choice award -- couldn’t deliver. The PSBs delivered it in spades.
“Wasted Youth,” a delicious and dramatic monologue by music producer Jim Steinman, appears on Meat Loaf’s Bat Out of Hell II: Back Into Hell (16/44.1 FLAC, RCA/Tidal). Appearing halfway through the set list of Mr. Loaf’s rock opera, this atmospheric recording is expansive, dynamic, and very well recorded. The PSBs cast a soundstage hugely wide and deep, and I shook my head at how balanced and clear Steinman’s voice was. Wind whooshed from channel to channel, while heavy breathing and assorted background noises crept in and out as this 2:42 track leapt from moments of repose to outright cacophony and back again. Yet even as I cranked up the volume knob of my Hegel H590 (301Wpc into 8 ohms), Steinman’s voice remained utterly composed, and the P5s’ tweeters sailed with an effortlessness that Paradigm’s Monitor SE Atoms couldn’t match -- they turned shouty at very high volumes. And when I swapped out the Hegel for NAD’s D 3045 (60Wpc into 8 ohms), I came to largely the same conclusion. Yes, there was a touch less finesse from the NAD across the board; otherwise, the Alpha P5s sounded the same: evenhanded, detailed, fantastic.
The Alpha P5s could rock out, too. With “Behold a Lady,” from OutKast’s terrific Speakerboxxx/The Love Below (16/44.1 FLAC, LaFace/Qobuz), the P5’s handling of the kick drum was seriously impressive. Midbass punch is hugely important in hip-hop, and while I was impressed with the P5’s reach -- well below 50Hz -- I was shocked by its control. The closely miked kick drum in this track dominates the center of the soundstage just behind André 3000’s lead vocal, with a properly concussive quality that the P5s actually delivered down to around 45Hz or so. I ran some test tones through the PSBs and confirmed that frequency, as well as meaningful output extending to just below 40Hz. I would be impressed with the PSB’s impact and slam for twice its price of $349/pair -- it seemed capable of almost all the extension of Definitive Technology’s Demand D9 minimonitor ($749/pair), which I reviewed last year (another Reviewers’ Choice), but with notably more control, and greater cohesion with the rest of the audioband.
Nor was the Alpha P5 flummoxed by high-resolution recordings. Playing “Younger (Acoustic Version),” from Seinabo Sey’s breakout album, Pretend (24/44.1 MQA, Universal/Tidal), I reveled in being able to hear the Gambian-Swedish singer’s subtle mouth movements and inhalations before she dives headlong into her biggest single. The MQA version on Tidal sounds phenomenal to begin with, but I was floored when Sey was presented, full-blooded and larger than life, in my listening room. She sounded incredibly lifelike, with inner detail and body by the bagful, and convincing dimensionality on three axes. Yet she also sounded smooth, clean, and concise. All of this was marked by an effortlessness that you rarely hear at this price. For that price, the P5s’ reproduction of women’s voices was perfect -- a word I don’t use lightly.
Elac, with its original Debut and now its Debut 2.0, in the last few years has made serious inroads in the market for minimonitors costing under $300/pair. While I haven’t reviewed a model from either Debut line, I’m very familiar with the tonal balance of the next level up, Elac’s Uni-Fi series, having in 2017 reviewed the Uni-Fi Slim FS U5 floorstander ($1499.96/pair and yet another Reviewers’ Choice). If forced to choose between the Elacs and the PSBs, I’d opt for the Alpha P5s every time. Whatever concessions PSB made in the bass -- not much -- it more than made up for with its exquisite midrange and effortless, linear top end. The Elac, by contrast, sounds rolled off in the lower treble: its sound is slightly darker, more closed-in.
But the Alpha P5 is not the [ahem] alpha and omega, the cure-all, the final destination for those still lost on the road to audiophile nirvana. It doesn’t offer hyperdetailed insight into larger soundstages. In my experience, you tend to get that kind of expansiveness only by tipping up the lower treble, which can also give a loudspeaker a more forward, dynamic tonal balance. Some folks want such pomp and circumstance from their loudspeaker, regardless of whether or not the music calls for it; different strokes and all. Also: as good as the P5’s tweeter is, it doesn’t offer quite the refinement and sweetness you can expect from far more expensive designs, such as PSB’s own Imagine series.
None of this should take away from the fact that the Alpha P5 is spectacular for the price, as evidenced by its control over large orchestral pieces such as Jerry Goldsmith’s original score for Star Trek V: The Final Frontier (16/44.1 FLAC, Epic/Tidal). Despite being released 30 years ago, the recording holds up admirably, and boasts extraordinary dynamics. The opening passage of “Without Help,” as played through my Hegel H590 with the volume ratcheted way up, exploded from the PSBs. Lateral soundstaging was first-rate, the string section playing through the left channel, the brass section through the right, each sounding as natural and organic as I could hope for at anywhere near the PSB’s price. I was particularly struck by the concision of the bass drums from the percussion section, which gave the music an unwavering foundation; and by the attack and decay of the trumpets, which can easily sound harsh if a speaker’s tweeter isn’t up to snuff, or if its tonal balance is too trebly. Not so here. I felt I could hear the entire orchestra clearly, without any editorializing by the speakers. Paul Barton conceded that in the accompanying anechoic measurements we might see a slight emphasis in the presence region of the midrange, something often done by designers to give their speakers a more vibrant, exciting sound. If so, he’s done it superbly -- the Alpha P5s sounded dynamic, but not artificially so.
Comparison: KEF’s LS50
I’ve used KEF’s two-way LS50s ($1499.99/pair) as my reference minimonitors for a number of years now. The LS50 has won near-universal acclaim from the hi-fi press, and tens of thousands of pairs have been sold since the model’s introduction, in 2012. Between its highly rigid, well-damped cabinet and its coaxial Uni-Q driver -- in which a 1” aluminum-dome tweeter nests coincidently within the cone of a 5.25” aluminum-magnesium-alloy midrange-woofer -- the LS50 is an engineering tour de force, and serves as a benchmark for just how good a well-executed two-way speaker can sound.
Swapping out the PSBs for the KEFs -- which cost more than four times as much as the Alpha P5s -- was beyond surprising. In terms of overall tonal balance, the two speakers sounded remarkably similar. In “Younger (Acoustic Version),” Seinabo Sey’s lovely voice sounded almost identical through both speakers, though repeated listens told me that it was slightly fuller, with a richer tonal density, through the KEFs. I also noted a subtle improvement in the reproduction of space through the LS50s -- Sey’s voice seemed more convincingly detached from the speaker cabinets.
The KEFs’ tweeters stretched their little legs with Goldsmith’s “Without Help,” from Star Trek V, conjuring greater soundstage depth, while the brasses in particular sounded a bit more refined. The margin of difference, however, was narrow. I had to listen to this track a couple times before I heard these differences. What was quickly apparent was that the PSBs were able to match the KEFs’ control of this track’s bleating tuba and foundational bass drum, while offering a solid 5-10Hz more extension into the low bass -- the KEFs’ lack of relative impact and slam was noticeable.
While it may be easy to dismiss this little minimonitor based on its price, its modest appearance, or both, that would be a big mistake. As well-built and attractive as the PSB Alpha P5 is, what places it among company as highly esteemed as KEF’s LS50, at more than four times the price, is the quality of its sound. It’s as complete a two-way design as you can hope to buy for anywhere near $349/pair. Perhaps another way of saying all that is that the Alpha P5 is the product of Paul Barton’s more than four decades of experience designing speakers. It’s an easy Reviewers’ Choice, and a frontrunner for Product of the Year for 2019. This is textbook loudspeaker engineering at its very best.
. . . Hans Wetzel
- Speakers -- KEF LS50
- Earphones and headphones -- NAD Viso HP50, PSB M4U 4
- Integrated amplifiers -- Hegel Music Systems H590, NAD D 3045
- Digital-to-analog converter -- Benchmark Media Systems DAC3 HGC
- DAC-headphone amplifier -- Oppo Digital HA-2SE
- Sources -- Intel NUC running Roon with Qobuz Studio, Tidal HiFi
- Speaker cables -- AudioQuest Rocket 33, DH Labs Q-10 Signature, Dynamique Audio Caparo
- Analog interconnects -- Dynamique Audio Shadow RCA, Nordost Blue Heaven LS XLR
- Digital interconnect -- DH Labs Silversonic USB
- Power conditioner -- Emotiva CMX-2
PSB Alpha P5 Loudspeakers
Price: $349 USD per pair.
Warranty: Five years parts and labor.
633 Granite Court
Pickering, Ontario L1W 3K1
Phone: (905) 831-6555
Fax: (905) 831-6936