These are my initial impressions of the Strata beta test unit’s sound. I am actually looking to trade in some equipment for a new integrated (more on that later). Which means a box should soon be going a few miles northwest from my house. The question is whether it will be addressed to PS Audio or to The Music Room.
I will be comparing it to my current system, and I am nervous about going from class A/B to class D. My philosophy is I need to hear a clear difference to report it, not “I swear amp X sounds better if I put on a tin foil hat”.
- In the blue corner: Onkyo CD/SACD player + Schiit Bifrost Multibit DAC + Stellar P3 + Exposure 2010 S2 integrated + Wharfedale Jade 3 + Kimber cables. A great system, very good tonalities. The Exposure is a Stereophile class A rated amplifier and the Strata is going to have to work HARD to beat it. Jade 3’s are rated B.
- In the red corner: the Onkyo + P3 + Strata + Wharfedales.
I also have a Sumiko subwoofer. I originally planned to use it, however I ran into practical issues. Unplugging / plugging cables from one amp to the other + turning on the amps, adjusting volume etc. takes too much time if I also must deal with the delicate sub cabling / grounding wires. So, I tried going the RCA to LFE route instead. But then I realized the two amps output quite different gains(?) to the sub, so I would also have to level match the LFE volume each time. That was simply too much trouble, so I decided to leave out the sub altogether. That way perhaps I will also get a cleaner impression of what the amps can do.
Amps level matched beforehand with an app. The Exposure/Schiit were warmed up long before the test. Strata had burned-in for 60h (and I may go back after a few hundred hours). All tracks are CD into digital input.
==BASS==
• Kei Koito – Organ Before Bach (incidentally, with a subwoofer this CD will rattle your martini glasses in the next room). Strata actually seemed a little less bassy but in fact it was more airy, controlled bass, less mushed together. There was more space and you can tell that we were in a church. From a bass standpoint, different but a tie. The Strata gives a much better impression of being in a church (reverb?). Also, I noticed a shocking difference. I was suddenly hearing all the clicking and clacking of the organ pedals. I had never heard that before. I then heard it (less) on the Exposure/Schiit but only because Strata had revealed it to me.
• Bill Evans, The Hilversum concert – Nardis. The bass seems deeper on the Exposure but it could be an illusion as it probably goes down as deep on the Strata, which has bass a bit more dispersed and airy, less concentrated. The Strata gives better bass textures: you can better hear the pluck of the strings and the wood of the instrument. This one is a tie: more texture and detail in the bass for Strata vs. more energy and fat in the lower bass for Exposure/Schiit.
• Blade Runner OST – opening title. For the Strata bass goes as deep but it is more spread out; there’s more air, better sound stage for the bass. Strata is more resolving in the bass. May not be as warm but it is also less mushy. This is a tie / a slight win for Strata.
• Harry Connick, Jr, 25 – On the Atchison, Topeka and Santa Fe. Both machines sound very nice here. Strata has a wee bit more texture than Exposure. Incidentally, when Harry sings “…and they’ll all wants lifts to Brown’s hotel” there is an instant when he sings with pursed lips or under his breath. I had never noticed that before; can be heard on the Exp./Schiit as well but only because I heard it through Strata first. A tie on bass.
• Chesky reference CD – bass track 27. Same: extension is similar, Exposure sounds fatter but better bass detail / textures for Strata. It’s a matter of taste and matchup with speakers and room.
==STRINGS==
• Bach, Suites for solo cello - Pierre Fournier. The Strata clearly reveals more details. It sounds much more like horsehair on strings. Fournier’s fingerwork on the strings is much more apparent. With bright speakers the revealingness could actually be a problem. This is a clear win for Strata.
• Bob Dylan, Blowing in the Wind – Freewheelin’. The Strata has more detail in the strings but less bass extension on the guitar. As a result Bob’s voice takes over a bit too much and the guitar recedes. Strata wins on sounding more like strings but Exposure wins on presence of the strings. This is a tie (dependent on taste). RANT: I cannot fathom why, in an otherwise beautifully recorded solo track, Bob’s voice comes from the center while his guitar comes from the right and his harmonica from the left??
==DRUMS==
• Bill Evans, The Hilversum concert – Nardis. Strata has more detail in the drum thwacks but Exposure sounds great too. A tie.
==PIANO==
• Harry Connick, Jr, 25 – Didn’t he ramble. Strata has less mushiness, more contrast, more details. Sounds more like a piano. Incidentally Strata exposed a short hum Harry makes. Win: Strata.
• Erik Satie – Gnossiene (Aldo Ciccolini). Can hear Ciccolini breathing in a few spots; that was new as well. Here Strata was beautifully piano-like and clearly more defined in the textures, airier. However Strata’s ruthless revealing nature gets a little bit in the way here. Exp./Schiit had a more “compact” sound with more midbass weight and was overall the smoother operator. Exp./Schiit wins this round. This one I might revisit in a few hundred hours as it strikes me as the sort of characteristic that could evolve.
• Debussy – Girl with the flaxen hair, from Preludes (Alain Planes). Strata sounds airier while Exposure puts more weight in the midbass and feels like rich Corinthian leather ; ) Both are superb. This is a tie.
• Bill Evans, Live at the Village Vanguard – Gloria’s Step. After solo piano, time for not solo piano. Strata has better high frequencies, makes piano less muddy and stand out more vs. bass and drums. Win Strata.
==VOCALS==
• Grieg – Peer Gynt. P. Jaarvi. On Solveig’s song (female) and the male Peer Gynt’s serenade, both amps were superb. Tie.
• Bizet – Carmen. (Callas / Gedda / Massard). Strata’s details are perfect but Callas’ voice has more bass which gives it more depth and more color on the Exposure. Ditto for Massard’s phenomenal Escamillo. Exposure wins.
• Diana Krall, Live in Paris - the look of love. Both amps are beautiful here, I hear no difference. Tie.
• Harry Belafonte, live at Carnegie Hall – Cucurucucu Paloma. Both amplifiers sound superb. With Strata Harry’s voice hangs holographically at about 6 ft height; it’s almost eerie. Win: Strata, but not by much.
• A.C. Jobim – Agua di Beber. Both sound great. Tie.
==HORNS==
• Miles Davis, Kind of Blue – Flamenco sketches. I was expecting Miles’ trumpet to sound shrill with the Strata but it did not. Coltrane and Cannonball’s saxes are a little more treble forward with the Strata’s, this is a matter of taste. Tie.
And now for the important bit:
My primary interest in the Strata was to see if it could make orchestras sound more dynamic, while remaining musical (not exactly class D’s reputation). I listen to a lot of symphonies and large orchestral works. When I increase the volume, sound goes up but it seems something is missing. Listening carefully, I would say that while the bass and the treble go up, it is almost like the midrange goes up less. That’s when I went back to the Stereophile review of the Jade 3’s (rated class B). I used to ignore J. Atkinson’s incomprehensible measurements, but finally took the time to “educate” myself and I now think the Jade’s might be harder to drive than I thought: the 6ohm / 86dB speaker actually measures at 83.5dB and although JA finds the phase angle benign, the impedance nevertheless spends its time at 3.2-4 ohms throughout the midrange. I think this is really a 4 ohm speaker. Turns out Exposure does not list a 4 ohm rating for this amp. Some bloke online measured 80w into 8ohms but only 105w into 4ohms + called Exposure and they did not recommend using it with 4ohm speakers. Could this be my problem?
==SYMPHONIES / LARGE ORCHESTRAS==
• St Saens – concerto pour piano n2 – Cecil Licad. Strata spreads the energy wider and taller but it’s a little light for my taste here. Exposure concentrates the energy too much in the center. This is a tie.
• Beethoven’s 5th. R. Chailly (Decca). Finally an improvement with big orchestral music! It’s hard to explain why but Strata has better instrument separation. Less mush. The soundstage is 2 feet taller and music more “effortless”. This is THE win for Strata!!!
• Smetana’s Moldau. F. Fricsay (DG). The Exposure seems to be playing from a 1 m circle in the middle. The Strata seems to be playing from a 3x2m rectangle. Cymbals at the end were small and coming from the floor on the Exposure while Strata’s were airier and had more bloom. Another win for Strata.
==GENERAL==
A few more tracks for enjoyment, not listening for any aspect in particular.
• M. Jackson – Billie Jean. Exposure has more midbass impact. Strata a bit more detail. Both sounded good. A slight edge to Exposure.
• B. Dylan, Freewheelin’ – Corrina, Corrina. Both great. Strata’s drums sounded a bit more like hollow objects (a good thing). Tie.
• Lalo Schiffrin, Bullitt OST – opening titles. The openings bass line is “angrier” with Strata which befits Bullitt. Win Strata.
• Dire Straits – Six Blade Knife. Exposure sounds great. Strata reveals just a smidge more clarity and detail in Mark’s guttural effects. Win: Strata by a hair.
• Duke Ellington and John Coltrane. While sax and drums sound fine, to my amazement the Duke’s piano is muffled and in the background. WTF? I have a hard time hearing it, it’s almost like he’s playing with a soft pedal. Moving to the Exposure I hear it too now but I guess I had never noticed it before. Something is wrong with this recording and it took Strata to hear it. I’ll call this a win for Strata and the CD will be my second CD to go into the trash after B. Evans’ Portraits in Jazz.
• J. Brown – Papa don’t take no mess. Both sound good but there is a little more clarity and detail from the Strata’s while the Exposures sound is a little bit more like tubes. This is a tie.
• J. Brown – Sex Machine. Very interestingly, the Strata is more revealing of Brown’s vocal idiosyncrasies. “Stay on the scene, like a sex machine” on the Exposure/Schiit becomes “Stay on the sceneh, likah a sexah machineh” on the Strata. Win: Strata.
SUMMARY
The Strata is quite a revealing little machine… At 60h, it is already an excellent amp: musical, with great soundstage. The details you get out of this thing are insane: it’s making me throw away a CD for god’s sake. If anything, the bass was a bit less full/fat than Exposure/Schiit but more detailed (and with the sub back in, it won’t matter). I think the boys from Boulder have crafted a wonderful integrated; as far as I am concerned the class D myth is busted wide open.
So…unless things change I think The Music Room will be getting a box. Thanks to the Whiz Kid for allowing me to pick up a Strata.
One last thing: I have a philosophical nitpick with Strata. I am not really the target market for this amp, which is, I think those who contemplate integrateds like the Hegel P120-190 and stream a lot. I couldn’t care less about streaming – I’m no luddite but I just don’t have the patience to troubleshoot all the stupid gadgetry. Despite its impressive performance, I therefore cannot help but wonder how much wifi, streaming, screen gadgetry noise bleeds into the Strata’s signal. Would it sound even better without all that? And how long before all this schtuff goes on the fritz or needs some “firmware update”? When changing inputs, it has already crashed twice – flashing blue logo – and needed a hard reboot. When I press the input button too quickly half the font temporarily goes yellow or purple. The Exposure has one -hardware- button (power), no screens, no antennas, no extraneous controls… I like simple. Simple works, simple is reliable. Simple is peace of mind. To each his own. Given the Strata’s musicality, detail, and power however, it will replace my current set-up, and I trust PS Audio’s design prowess and quality will change my mind about antennas and screens.