PSB Launches New Flagship Synchrony Speakers: High Performance Meets Value?

Just ahead of the company’s 50th anniversary next year, PSB held an online event on Thursday, September 16th 2021, to mark the official launch of two new flagship loudspeakers, the Synchrony T600 floorstanders ($8,000/pair) and the Synchrony B600 stand-mount speaker ($2,500/pair). The livestream included product giveaways, an in-depth look at the new designs, and a live Q&A session with PSB founder Paul Barton and IsoAcoustics president Dave Morrison, moderated by Ian White, the editor-in-chief of ecoustics.com. I’ve been a fan of Paul Barton’s speakers for years. PSB speakers consistently offer tremendous value, and tend to have a full-bodied and natural-sounding midrange that lets vocals really shine. The brand’s titanium dome tweeters produce miraculously unfatiguing and enjoyable high frequencies, despite whatever prejudice you may or may not have against metal domes. Normally, a behind-the-scenes look at new flagships from a designer whom I admire so much would be something I’d get really excited about. Instead, I was just annoyed. Like millions of other Jewish people (at least a few of whom must be audiophiles!), I was unable to tune in for PSB’s event because September 16th was Yom Kippur, the most important Jewish holiday of the year. Honestly, I can’t believe that this stuff continues to happen, year after year. You can add major religious holidays to your calendar with a couple of taps on a smartphone! There’s really no excuse for companies (or school systems, or any institution) to plan important events on days when so many people will be automatically excluded. If you wouldn’t schedule an event on Christmas or Easter, don’t do it on Rosh Hashanah or Yom Kippur. (Ok, end of rant.) Luckily, the video remains available on PSB’s YouTube channel, so I was able to play catch-up the following day, and these speakers really do seem worth getting excited about. Featuring all new drivers, new crossovers, and new enclosure designs, the Synchrony T600 and B600 speakers are described as “the clearest expression yet” of PSB’s design philosophy, which applies science to better serve the music.

The first thing you’ll notice about the new Synchrony speakers is their new industrial design, which forgoes the gentle curves that made PSB’s previous flagships, the Imagine T3, so elegant. The long-discontinued Synchrony speakers from the mid 2000s also featured curved cabinets, but the new Synchrony T600 and B600 are strictly rectilinear affairs, with nothing but straight lines and right angles as far as the eye can see. Whether you will prefer this shape is of course a matter of taste; I gravitate toward curves, but the classic simplicity of a rectangular box can have its own appeal if done well. (I’ve noticed a trend toward embracing the rectangle in loudspeaker design over the last several years. For example, KEF’s Reference series and Monitor Audio’s Gold speakers used to be curvy, but the current versions of both are as square as George McFly. The inexpensive speakers that Andrew Jones designed at Pioneer had curved cabinets, but when he went to Elac, it was back to rectangles. At the other end of the price spectrum, you can spend $63,600 on a pair of rectangular aluminum boxes in the form of Magico’s imposing A5 speakers.) In any case, PSB’s new Synchrony T600 and B600 boast excellent build quality, and the two available furniture-grade finishes (satin walnut veneer and high gloss piano black) are reportedly a cut above anything PSB has offered in the past. Both speakers come with acoustically transparent, magnetically attached grills.

Underneath their simple but tasteful exteriors, there is, of course, a whole lot of engineering going on. During the live video event, Paul Barton discussed how he met Dr. Floyd Toole in 1974, and that soon thereafter, PSB became the first audio manufacturer to take advantage of the research facilities at the Canadian National Research Council. I remember reading elsewhere that, for eight years, PSB was the only loudspeaker company to make use of the now-famous anechoic chamber at the NRC, and it was during this period that Dr. Toole conducted some of his most influential research on the correlation between objective loudspeaker measurements and the subjective preferences of everyday listeners. In the intervening decades, Paul Barton’s scientific approach to loudspeaker design has not changed, but the science itself has advanced a great deal. The design process for the new Synchrony speakers involved the use of laser vibrometry equipment, and the latest finite element analysis software to model everything from driver cone geometry, to crossover design, to cabinet bracing. Of course, prototypes were measured in the NRC’s anechoic chamber, and the objective data was then correlated with extensive listening tests. The result of this effort is “a new range of speakers that deliver superb tonal accuracy, thrilling dynamics, impactful bass, transparent midrange, pinpoint imaging, and exquisite micro-detail,” according to PSB. And in a first for the company, the new speakers incorporate acoustic isolation technology designed for PSB by IsoAcoustics.

PSB Driver and Crossover Design

The Synchrony T600 utilizes a trio of 6.5-inch woofers and a 5.25-inch midrange driver, all featuring woven carbon-fiber cones, mass-loaded rubber surrounds, die-cast aluminum baskets, and an advanced motor structure that ensures a constant magnetic force in the gap of the voice coil. The B600 stand-mount uses a single 6.5-inch mid-woofer. The 1-inch titanium dome tweeter used in both the T600 and B600 employs a neodymium magnet, and is cooled by ferrofluid. The tweeter sits inside a waveguide that’s approximately 2.75 inches in diameter. Directly in front of the tweeter is a custom-designed acoustic lens that is said to improve dispersion and off-axis response. Together, these new drivers result in “wider bandwidth, higher maximum output, higher efficiency, better power handling, and reduced harmonic and intermodulation distortion,” according to PSB. The blending of these drivers is handled by the most advanced crossover that PSB has ever built, using high-voltage poly film capacitors and oxygen-free wire. All of PSB’s literature mentions an “amplitude-perfect Linkwitz-Riley acoustic crossover,” for both the T600 and B600. Indeed, a careful look at the spec sheets reveals that the B600’s crossover is a 4th-order Linkwitz-Riley centered at 2200Hz. And in the T600, the crossover from the midrange to the tweeter is a 4th-order Linkwitz-Riley centered at 1800Hz. But the bass-to-midrange crossover at 450Hz is a 3rd-order, Butterworth design. And as you’ll see in a moment, there is even more crossover complexity at work within the woofer system. The prize for all this design work is said to be a “remarkably flat frequency response, so that every sound you hear is true to nature.”

The tweeter on this speaker, with 1 watt into it, can produce 95dB. That doesn’t necessarily equate to how loud it will play, but the point is, it’s a very efficient design.

— Paul Barton

PSB Synchrony Structure

The new Synchrony speakers feature MDF enclosures with more extensive internal bracing than in any other PSB speaker in the company’s history. The goal of this bracing is, of course, to minimize cabinet resonances, which can blur transients and cause uneven response. Taking this concept a step further is the new 5mm-thick solid aluminum plate that covers most of the baffle’s surface on both the T600 and B600. The aluminum plate is designed to suppress “baffle talk” — the excitation of the front baffle by vibrations coming from the drive units, or from other parts of the cabinet. The aluminum plate is decoupled from the rest of the enclosure by 10 “isolation cups,” which work with the plate to help preserve the fine detail that can be lost when the baffle is allowed to vibrate. Standing just over 41 inches tall and weighing in at 77 lbs, the Synchrony T600 has a fairly substantial cabinet that is divided into 4 separate chambers. The midrange driver and tweeter share a sealed chamber at the top of the tower, while each of the three woofers gets its own identically-tuned, rear-ported chamber. This configuration is designed to break up standing waves inside the enclosure. The T600 towers sit on four outrigger stabilizers, each of which attaches to a slightly customized version of the IsoAcoustics Gaia II isolators. The IsoAcoustics isolators decouple a floor-standing speaker from the floor it sits on and prevent mechanical energy from  being reflected back into the enclosure. The isolators are designed to provide “a high degree of isolation while resisting lateral movement and oscillations to maintain alignment with the listening position.” The result is said to be a wider soundstage with more precise imaging, and improved detail and transients. (I have heard a few demonstrations at audio shows, and was surprised at how effective these devices seemed to be.) A set of 8 IsoAcoustics Gaia II isolators costs $600 if purchased separately. Clearly, Paul Barton is convinced that they work well enough to include them with every pair of Synchrony T600s.

The (three) woofers are a transitional design, meaning all woofers produce low frequencies, but the bottom woofer rolls off before the middle woofer, which rolls off before the upper woofer, and only the upper woofer rolls off to the midrange driver, which then rolls off to the tweeter.

— Paul Barton

PSB Synchrony Custom Tuning Options Aplenty

Like PSB’s previous flagship floorstander, the Imagine T3, the T600 is a transitional-array design, with three woofers that cover progressively narrower frequency bands as you move down the speaker. The top woofer covers the entire bass region, from the lowest frequencies all the way up to the crossover point with the midrange driver. The middle woofer starts at the bottom as well, but rolls off much lower, well before the midrange crossover point. Finally, the bottom woofer plays only the lowest frequencies. Barton says that this unusual woofer array produces smoother bass response because it “randomizes” the phenomenon of floor bounce, in which the low-frequency sound waves that bounce off the floor interfere with the sound coming directly from the woofers. Each Synchrony T600 has 3 bass-reflex ports in the rear of the speaker. The T600s ship with 2 sets of port plugs, so users can experiment and customize the bass output to better suit their listening rooms. You can leave all 3 ports open, or plug any one port, or any 2 ports. During the live stream, Barton mentioned that a user might even get the best results from plugging different ports in the left and right speakers, depending on the room setup. If you like to tweak, choosing the best-sounding combination among the many possible permutations will be part of the fun of setting up a new pair of speakers. For some, it may sound a little daunting. But the tweaker’s delight doesn’t end there. Also on the rear of each T600 are 3 sets of binding posts, allowing for bi-wiring/bi-amping, or tri-wiring/tri-amping. Or, as Barton mentioned in the video presentation, you can short out the bottom woofer. “By shorting the bottom woofer,” he explained, “you’re only reducing some of the very lowest frequencies, which could complement the way in which you set this up in your room.”

The B600 stand-mount speaker is, of course, quite a bit more straight-forward. But according to PSB, its 6.5-inch carbon-fiber woofer and 1-inch titanium dome tweeter deliver “wider bandwidth, higher efficiency, better power handling, and reduced harmonic and intermodulation distortion” when compared to any previous 2-way stand-mount from the company. Like its larger sibling, the B600 boasts a remarkably flat frequency response, extensive internal bracing, and the 5mm-thick solid aluminum plate on the baffle. You might expect, as I did, that the optional 24-inch-tall stands designed to support the B600 (which sell for $600/pair), would include a version of the IsoAcoustics isolators. But you’d be mistaken. Instead, PSB did something much cooler. On the bottom of each B600 speaker, there are four small isolation feet, custom-designed by IsoAcoustics for this application. In the livestream, Dave Morrison from IsoAcoustics explained that these tiny feet are just scaled-down versions of the larger isolators used on the T600. And because they are attached to the bottom of the B600 speaker itself, the user can enjoy the sound-quality benefits with any speaker stand, not just the dedicated ones offered by PSB. The dedicated stands do provide a non-resonant connection to the IsoAcoustics isolation feet, along with the additional stability of a bolted connection.

I don’t do anything that isn’t good value, and I don’t do things that aren’t going to do something to the product. People throw a lot of things at products that aren’t necessary, and sometimes they throw things at products that make it even worse. Value is a really high priority and I’m proud to say it’s something we’ve stuck to over almost 50 years.

— Paul Barton

PSB Value Proposition

PSB speakers are known for providing excellent value, and although the new Synchrony speakers are far from cheap, I think it’s commendable that the company hasn’t followed the trend of ever-increasing prices for flagship-level products. At $8,000/pair, the Synchrony T600 costs only $500/pair more than the Imagine T3 did when it launched in 2015. The T600 also uses more advanced drivers, and is built better than the T3. And if you account for inflation, the T600 is actually several hundred dollars cheaper than the T3. I expect that these speakers will be very successful for the company, but I also believe that the T600 would still sell if PSB asked $10K/pair for them. The only disappointing piece of information to come out of the livestream was the surprising fact that PSB does not plan to launch a dedicated Synchrony 600 center-channel speaker in the near future. If there is demand for such a speaker, I expect that it will show up eventually. But for now, home theater customers are encouraged to use one one of PSB’s high-performance on-wall speakers, the PWM2 ($1,500 each) or PWM3 ($2,500 each), as a center-channel speaker or as surrounds, in conjunction with the Synchrony T600 and B600. The company says that these premium on-walls “have been voiced and have very similar dispersion characteristics as the Synchrony T600 and B600,” but they certainly don’t provide an aesthetic match. It remains to be seen whether Synchrony customers will be satisfied with this stopgap solution, but I doubt I would be. Other than that wrinkle (and the fact that the livestream event was apparently for gentiles only), the Synchrony 600 speakers look like winners to me. I may not be totally sold on the rectangular boxes, but I could be in the minority there.

Do you like a curvy look for high-end speakers, or is the tried-and-true box shape a classic for a reason? Share your thoughts in the forum below.

Unless otherwise indicated, this is a preview article for the featured product. A formal review may or may not follow in the future.