Sidebar 3: Measurements
I preconditioned the Bryston 28B-SST by running it at 330W into 8 ohms for an hour. The THD+noise was 0.00265% at the start; by the end of the hour, it had dropped slightly, to 0.00218%. The amplifier's heatsinks were way too hot to touch after 60 minutes, but despite the thermal abuse, the amplifier didn't turn itself off.
The amplifier was non-inverting from both its balanced and unbalanced inputs. The voltage gain into 8 ohms was 28.75dB from both inputs with the gain switch set to "29dB/1V," 22.9dB with it set to "23dB/2V." The input impedance was…
I had planned to feature a few intriguing new products I saw at CEDIA's Expo 2007 held last September in Denver, but I did that on the Stereophile website. Instead, I'll just tell you about the only big audio trend I saw there: HDMI.
What? Ain't that a video interface? Sure, but HDMI can also handle multiple channels of audio in all current high-resolution formats, including DSD and uncompressed PCM. Everywhere I went at the Denver Convention Center, manufacturers were shouting that their players had HDMI outputs and their pre-pros and AVRs had multiple HDMI inputs, although…
With all the connection options, installing the DTC-9.8 can be complex, though it need not be. To get started, I simply connected the six XLR jacks to my Bryston 9B-SST power amp, the HDMI output to my plasma display, and my Denon DV-3910 universal player, Pioneer Elite BDP-HD1 Blu-ray player, Oppo DV-980H universal player, and cable-TV box into HDMI inputs 1–4. That was it: 11 wires. My heap of discarded analog and S/PDIF cables was more than ankle deep.
I then went through the now-familiar setup procedures of associating the physical inputs with the logical names that appear on the…
The 6dB difference in level between the Oppo's PCM and DSD outputs remains (Oppo and Integra are still pointing fingers at each other), but the volume control fixes that. Also, with PCM from SACD, the Integra displays the sample frequency as 88.2kHz, but with DSD the display reads "44.1kHz." Oppo explains this by quoting the HDMI 1.2 spec: "For Super Audio CD, the SF bits are typically set to 0, 1, 0, to indicate a Sample Frequency of 2.8224MSamples/s (ie, 64x44.1kHz)."
Nonetheless, I was a bit unnerved by all this. It may contribute to my preferring SACDs transcoded to PCM by the Oppo…
Sidebar: Recordings in the Round
HAYDN: Die Schöpfung
Miah Persson, soprano; Topi Lehtipu, tenor; David Wilson-Johnson, baritone; Mozarteum Orchester Salzburg & Salzburger Bach Chor, Ivor Bolton
Oehms Classics OEH609 (2 SACDs)
Haydn's joyously spectacular oratorio The Creation has been one of my favorite pieces since I was in college, when Vladimir Ussachevsky introduced me to the remarkably forward-thinking opening depiction of Chaos. What tone painting—and what follows is melodious and uplifting. I own four other recordings, but this one joins the top of the list for its…
When I arranged to review the Bryston 28B-SST monoblock power amplifier, I wanted to be certain that the 1kW amplifier wouldn't be starved for current. Bryston advised me that Plitron, who manufacture the 28B-SST's toroidal transformer, also make Power Isolation Units (PIUs), under the brand name Torus Power. Torus explained that its PIUs combine surge suppression with massive toroidal transformers to provide AC power conditioning and protection from voltage surges.
For this review, I was supplied with Torus's RM20 ($3000), a PIU that uses a single 2400VA toroidal transformer to supply…
P.D.Q. BACH: WTWP Classical Talkity-Talk Radio
Prof. Peter Schickele and the Usual Cast of Clowns; many instruments, some of which you'll recognize
Telarc CD-80295 (CD only, as if we had to tell you that). Robert Woods, Elaine Martone, prods.; Jack Renner, Michael Bishop, engs. DDD (as if we had to tell you that, too). TT: 61:39
When confronted with the transcendent ouevre of the late P.D.Q. Bach, this reviewer frequently finds himself at a loss for words, but here faced with what is not only the crowning glory of P.D.Q.'s opus, but an effective satire of contemporary "classical…
Recently, I assessed four disparate room-correction systems based on digital signal processing (DSP): Copland DRC205, Lyngdorf Audio RoomPerfect, Velodyne SMS-1, and Meridian DRC. I concluded that Meridian's approach—which applies IIR (Infinite Impulse Response) "anti-resonance" filters to suppress room resonant modes, if only partially—was, in many respects, the best. What I particularly like about Meridian DRC is that, unlike the Copland and Lyngdorf processors, its approach to system tonal balance is largely hands-off. Yes, it lightens up the extreme bass a little, as you'd expect, but it…
When Robert Harley reviewed the Phantom Acoustics Shadow in the December 1989 Stereophile, Vol.12 No.12, he was clearly impressed: "The improvements in low-frequency definition, dynamic impact, and LF tonal neutrality were dramatic." And yet the Shadow soon faded into obscurity. Moreover, so far as I am aware, no one in the domestic audio industry has since attempted to resurrect the idea of active modal absorption (footnote 2). Considering the DSP power now readily available, this is surprising—we almost certainly could do a better job today than the Shadow did two decades ago. In…
When it comes to loudspeaker drivers, Dynaudio has earned an enviable reputation for quality and reliability. To use an automotive analogy, they are the Mercedes Benz of the driver universe. If you're a speaker builder, the odds are that you have already experimented with these drivers. And even if you're not a speaker builder, it's quite possible that your speakers use Dynaudio drivers. After all, some of the finest speaker systems in the world do. A case in point is the Duntech Sovereign, which single-handedly embodies almost the entire Dynaudio catalog.
Surprisingly, Dynaudio's line…
