Audio Adventure: Extreme Audio    January 1997

POLYFUSION 920 DIGITAL TRANSPORT AND 805 HDCD® DAC

Getting 'Fused to the Music by Tony Rago

Remember the Moog Synthesizer? Popular throughout the late Seventies and Eighties and used by some performers today, it had a cool sound and was built to last. Alan Pearce and Ron Folkman were involved with Moog in various capacities for a number of years. Then in 1975, the two of them started Polyfusion Electronics. A year later they developed their own Polyfusion Synthesizer. Polyfusion Electronics, the parent company of Polyfusion Audio, has been developing circuit designs for the medical and robotics industries, for test and measurement systems, and they make a hand-held computer used by the beer industry to measure carbon dioxide content. They also make a patented feedback controller called the Polyfusion 755 and other pro audio equipment. And they design consumer products: amps, preamps and digital equipment. Here we will examine the 920 Transport ($2,900) and the 805 DAC ($3,250).

Looking Inside

The 920 uses the highly regarded Philips CDM 9 Pro transport, has an outboard DC power supply designated the Model 355, superior isolation of digital and analog stages and a sophisticated clocking circuit. A look inside reveals that this transport was put together with care and effort. For outputs, the 920 has one ST fiber-optic digital out and an RCA coax. Polyfusion makes their own two-pin interface, the Digi-Link, which they claim is superior to coaxial. Of course you can't use it unless you use a Polyfusion DAC, such as the 805. The 805 uses two Burr Brown PCM 63 PK DACs, one per channel (20-bit resoludon) and the Pacific Microsonia PMD-100 digital decoder/filter with 8X oversampling. The analog stage uses Polyfusion's own custom three-pole 40KHz low-pass analog domain filter for "ultra low noise and low distortion" says Polyfusion. The front panel has a control knob to select one of the five digital inputs and lights: amber for HDCD® decoder active; green to verify input frequency (32KHz, 48KHz and 44.1KHz); yellow to indicate De-emphasis status (older analog-mastered CDs often use pre-emphasis with noise reduction techniques); red for mute.

This unit sends the digital signal to Polyfusion's exclusive waveshaping circuit to minimize jitter, then to the DAC module. The decoded signal is then processed by the HDCD® filter/decoder. The rear panel sports the inputs, outputs and a level control. I used this control set at max; othervise, the 805 was too soft, without enough get up and go. The 805 also uses the 335 DC power supply and you can buy one to handle both the 805 and the 920, saving $450. This power supply uses a large toroidal transformer and connects with the 805 and 920 via an umbilical and attaches to the AC line via a detachable power cord.

Going To The Details

At the prices of these units, we expect grace and refinement. And we get it. Resolution is top notch. Give Miles Davis' Kind Of Blue (Columbia CK 40579) a whirl. You'll be astounded. I won't tell you about such little details as hearing a cymbal harmonic for the first time or being able to identify mike setup. Ah, heck with it! Yeah, I heard more details, like just how good Miles was when he used the plunger on his horn and the added harmonic life in the cymbals. (They glowed with life.) Resolution was so good I could discern the difference between Bill Evans and Wyn Kelly on piano. Kelly plays on "Freddie Freeloader," and seems a bit awed by Miles and Coltrane—maybe not quite letting go. Evans, on the other hand, seems very sure of himself, letting fly while still retaining his delicate touch. This is subtle stuff, all right. But the Polyfusion DAC is so involving, so resolving, so transparent, it reaches in and grabs you. Now this isn't analytical, clinical or etched detail. It's just excellent resolution.

Want to hear about the super imaging? The Sonic Frontiers Power 2 amp excels in allowing images to float and surrounds them with air. The Polyfusion combo takes the signal and does this before the Power 2 gets it, so there's even more air, more palpability. If you had an amp like this and trans parent speakers like the Martin-Logan SL3s, you'd owe it to yourself to try the Polyfusion system. You may just be swallowed up and digest ed by the music.

A word of caution. The 805 needs plenty of burn-in time. At first it will sound way too laid-back, non-dynamic, sluggish in pace and bass shy. Whewl Fact is, I braced myself for writing a negative review of this unit until break-in changed it completely. Gone was the lightweight bass. Dynamics became a strong point.

Better & Better

Next I spun some HDCD-encoded discs and oh, my! You haven't heard HDCD® till you've listened on this set-up. Air, air and more air. A soundstage to die for. Imaging so intense, you'll be forgiven for thinking you've been transported to a spiritual realm. Transients that just cut through the air, and bloom, bloom and more bloom. Decay that would do a zombie proud. Listen to Doug MacLeod's You Can't Take My Blues (California Audio Labs CLR-001). On "Things'll Be Better, You'll See," cymbals billow with air. And check out the fiddle on "Papa John." I never knew just how fabulous a recording this was until I heard it with the Polyfusion stuff. Try any Reference Recording or Golden String HDCDs, and you will also fly away. Don't fret; regular CDs sound better, too, with the Pacific Microsonics filter, especially within the Polyfusion Audio 805. But I must temper my enthusiasm a bit here. While the 805 did musical cartwheels with the 920 transport, it didn't do very well with the Audio Alchemy DDS Pro. With this transport, based on the Pioneer Stable Platter, the 805 was lacking in lower octave weight and had a narrow soundstage. Depth was still great, but right-to-left spread was simply not there. The DDS Pro, with other units, doesn't have a problem in the bass department and its soundstage is generous. It loved any other converter I put with it. Perhaps the 805 is monogamous—created to go with its natural mate only.

Praise The Lord And Pass The 920

On the other hand, the 920 is a super transport on its own. I doubt if you could get better at this price. You want lots of bass? Get a 920. You want wads of resolution? Get a 920. You want transparency? Get a 920. You want sweet, airy highs? Get the idea? And it will do its best stuff in combo with the 805. But even on its own, it really rocks, it moves with jazz. Tracking is exceptional. Ease is the key word here, the sense of music evolving in front of you without strain. You'll never feel fatigued with this set-up paving the musical way. Musicians (and recordings) as diverse as Chico Freeman on Emissary (Clarity Recordings CCD-lOl5), Sheryl Crow, Tuesday Night Music Club (A&M Records CD 0126) or the Mozart Piano Concertos KV 271, 595 (Chesky CD156), the performance was always involving. The Mozart in particular revealed this transport's wonderful ability to plunge to the depths, as the double basses set a deep foundation. Piano tones were realistic and strings were especially sweet and airy. Oh, and soundstage freaks will love this transport. Chico Freeman's "La La Means I Love You" has a very deep and layered stage, with nice left to right spread. The 920 sets each instrument in place with plenty of air around it. The 920, especially with the 805 DAC, opens up the music and dynamically propels each performer in such a way you may sometimes forget you're listening to a merely Meat system. Well, it makes for a nice illusion, anyhow! On Emissary, catch the flamenco guitar on "Mucia," with Freeman on soprano sax. Super. More than that. Gorgeous.

Such refinement, of course, costs dearly. And that cost troubles me. A digital converter priced at over three grand should do better than others costing less. The 805 was able to do this only with the 920 transport. With the DDS Pro, I got better performance from DACs costing under $1,000. The 920, on the other hand, is a winner in any setting. Though Polyfusion could offer more in appearance. While neither unit looks bad or cheap, they don't convey the impression of an exotic or expensive piece of equipment.

Still, for performance, the combo is hard to beat. Plenty of detail without getting clinical. Excellent transparency and imaging. You may be able to get close with less expensive gear, but you'll miss out on that last iota of realism, that last speck of detail, that last drop of natural liquidity, that last dot of pure timing. So—dig into your pocket, and get it all with the Polyfusion 920/805 combination. Expensive, yes. Worth it?

There's No One Here Called Rago!

Don't take my word for it. Yes, the 920 is one of the best transports in the world; yes, the 805 is astounding. But there's plenty of competition at this price point. So shop carefully. But—if you like transports and DACs from the same manufacturer, you can't go wrong with Poly. In fact, you owe it to yourself to check out the Polyfusion 920 transport and 805 HDCD® D/A converter. Me? Well, I'm bolting the door and shutting off the phone. Pulling down the blinds. Leaving a note to the milkman: "Gone—fused to the music." And sitting here in the dark, just feeding CDs to Poly.

Copyright © 1997 Audio Adventure. All Rights Reserved. Used by permission.

HDCD® and High Definition Compatible Digital® are registered trademarks of Pacific Microsonics, Inc.