Peachtree Audio nova125 integrated amplifier Page 2
Class-D amplifiers for serious audio listening are now offered by the likes of Cary Audio, Mark Levinson, Micromega, and Jeff Rowland Design Groupnot to mention newcomers like Nuforce. And there's no reason a switching power supply can't be used with tubed amplifierseven single-ended ones such as the MiniWatt N3 integrated ($349). I'll leave it to the tech types to carry on the discussion.
I'll take mine on the rocks
Peachtree Audio's nova125 uses an ASX250 module from ICE, who developed it in Denmark. The company is part of Bang und Olufsen. The folks at Peachtree Audio love the ASX250, and maybe they should.
At any rate, the nova125 has to use class-D modules for reasons of cost and size. Otherwise, there's no way they could have offered this product for $1499 with power-output ratings of 125Wpc into 8 ohms or 200Wpc into 4 ohms.
Those power ratings are not insignificant. As another amplifier manufacturer recently told me, some loudspeaker companies finagle, or fib, when it comes to sensitivity and impedance, to make a loudspeaker load seem easier than it is. (Amplifier manufacturers do plenty of finagling, too.) That "8 ohm" speaker may have a minimum impedance of 4 or even 2 ohms. That 4 ohm speaker may dip to 2 ohms. In the past, some class-D modules have struggled to pump out enough current.
Even when a loudspeaker load is easysay, an even 6 ohmsthat extra oomph from an amplifier, that current drive, will result in more dynamic sound, which, in turn, is an easier load on the listener.
I knowI adore flea-watt single-ended-triode amplifiers. Don't expect decisiveness from me. Or easy answers. Or even the right questions. According to Vanity Fair's Michael Lewis, President Obama is big on Heisenberg's uncertainty principle: "'Me asking the question changes the answer.'" Better to have someone ask the question for you. Remember that at your next business meeting.
Up and listening
Have class-D amplifiers entered a new era? I haven't sought them out, so I can't answer. But based on the Peachtree Audio nova125 and its ICE ASX250 module, I'd say yes. Of course, the sound of the nova125 does not entirely depend on those cool Danes from ICE.
I played CDs from the digital output of my Sony XA-777ES SACD/CD player, setting aside my Musical Fidelity V-DAC II; and SACDs from the Sony's two-channel analog output. The single set of RCA analog inputs made it a pain to use my EAR 834P preamp, Rega P25 CD player, and Goldring 1042 moving-magnet cartridge, not to mention my discontinued Sony FM tuner. Sony, why such baloney?
I used my two reference speakers: the Harbeth 30.1 Monitors and the Triangle Comète Anniversaires, both said to be easy loads. The Harbeth's claimed sensitivity is 85dB/W/m with an even 6 ohm load. The Triangle is said to deliver 90dB with a minimum impedance of 4.4 ohms. Neither speaker demands bone-crushing amplification, but both can respond to it.
The Peachtree's 125Wpc of power, though not required by either speaker, made both models come dynamically to life. Less powerful amplifiers did notincluding my solid-state LFD Mk.IV LE and my tubed Unison Research Simply Italy, with its 12 Treviso watts per channel. The Simply Italy delivered tight bass but eventually ran out power, like delicious pasta with too little sauce. Trade one of these amps for class-D? Nah.
The nova125 is for those who think $1499 is enough to pay, and who want to decide once. Sorry, but you will have to decide about S/PDIF and/or USB cables.
The nova125's strengths were not what I'd expected. Better-than-average tonality, for instance. Strings were full-bodied and sweet. Bass had bite, but not too much. Bass was generously presented and, overall, well defined: firm but not exactly tight.
An old-fashioned light bulb went off in my dim brain. Was the nova125 designed, on purpose, to treat subprime source material generously? Thanks to my obsolete computer, I can't tell you about MP3 downloads or Internet radio or hi-rez downloads. But I found the nova125 exceptionally kind to less-than-stellar CDs.
Take (for 20 bucks or so) Carlo Maria Giulini's cycle of Brahms symphonies, recorded live with the Vienna Philharmonic, originally issued in the 1990s by Deutsche Grammophon and recently reissued by Newton Classics (8802063). These splendid, almost glowing performances have a somewhat opaque, diffused sound. They reminded me how lucky I was to hear Giulini conduct Brahms in concert.
The nova125 preserved these recordings' tonal qualitiesthe way the Vienna Philharmonic (especially the brass) sounds, the way the hall sounds. I'm not sure I've heard the first bars of Symphony 1 beaten out with more decisive force. When I first heard Giulini conduct Symphony 4, 40 years ago in Providence, Rhode Island, I almost fell out of my seat. Hats off to Peachtree Audio and to the ICE modules for conveying some of that power (footnote 1).
I've been listening to Wilhelm Kempff's first cycle of Beethoven's piano sonatas"The legendary mono recordings" of 195156 (Regis RRC9010), available intermittently from Berkshire Record Outlet. Prowl the website (broinc.com) for a "Featured Restock (!)." Kempff was still in his primeas he wasn't, quite, for his later Beethoven cycle in stereo, on DG. The nova125 somehow enhanced the dynamics and the tonal quality of Kempff's playing, giving the recordings added weight, body, richness. (The transfers are excellent.)
Why not try LPs? Because I had to disconnect the SACD player to free up the analog input, that's why. I used my EAR 834P phono stage (now almost 20 years old), Rega Research P25 turntable and tonearm, and Goldring 1042 MM cartridge. I'd exchanged the Rega's stock felt record mat for a Music Hall cork mat ($49.95), for what I thought was tighter, better-defined sound.
Even so, I found the sound somewhat bass-heavy and slightly congested. What was I hearing? The original jazz recordings from the 1950s and '60s that I was playing? The Rega? The cork mat? The EAR 834P? The tubes? Listening to vinyl did confirm my suspicion that the nova125 sounded innately warm and slightly softperhaps just the ticket for whatever comes into its asynchronous USB input, assuming you can use it.
What accounted for the sound: the line stage, the tube buffer, the ICE modules? I tried the nova125's headphone outputwhich runs directly from its line stage and does not go through the ICE moduleswith my Audio-Technica ATH-AD900 headphones. The story was the same: somewhat warm, slightly soft, and not at all displeasing.
What I didn't hear was top-tier resolution. All the air wasn't there, which became immediately apparent when I turned on my Music First Audio Baby Reference preamplifier (ha!) and Quicksilver Silver 88 tubed monoblocks. Comparatively, for me, the nova125 suffused the music with a slight velvet fog. Call it the Mel Tormé of integrated amps. Better that than the Eddie Fisher. Incidentally, I heard little or no difference with the tube buffer in or out of the signal path.
Again, I thought of retro. The sound reminded me of some solid-state amplifiers of the 1970s: the GAS Son of Ampzilla, the Audionics CC2, the original B&K ST-140 power amplifierB&K ST-140 before they goosed it from 70Wpc to the magic 100Wpc (but into what loads?).
My gosh, what would Al Bowlly (18991941) sound like with the nova125? Like the greatest male popular vocalist who ever lived, that's who. I think John Atkinson's grandmother was a big fan. My granny was.
I'm sure that more "high-end" manufacturers are now working secretly and feverishly on class-D amplifiers. When they introduce them, they'll proclaim class-D the greatest sonic advance since . . . 1932? (footnote 2)
Meanwhile, for $1499, Peachtree Audio has delivered a plum.
Footnote 1: In my opinion, Giulini's Brahms is equaled only by that of Kurt Sanderling with the Staatskapelle Dresden (Eurodisc 69220-2-RV, long deleted). Giulini and Sanderling were close. When Giulini's wife fell ill, he suggested that Sanderling take the Los Angeles Philharmonic on its world tour.
Footnote 2: I'm sure that audio engineers of the 1930s, who worked with AM radio, knew about all this switching shit and much more. There are reasons why Holger Stein, of Steinmusic, collects antique radios and everything he can read about them.