To take these measurements, I used Stereophile's loan sample of the top-of-the-line Audio Precision SYS2722 system (see the January 2008 "As We See It" and www.ap.com). Before doing the testing, I ran the Musical Fidelity AMS100 at one-third its rated power for 60 minutes, which thermally is the worst case for an amplifier with a class-A/B output stage. However, an amplifier with a class-A output stage runs cooler when under load. At the end of that period, the chassis was warm, with a temperature of 104°F (40°C), though the heatsinks were hotter, at 116°F (46.6°C…
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Today's New York Times carries a brief obituary notice of the passing of audio innovator, Peter Pritchard, on August 23 in Austin, Texas at the age of 83. Peter founded Audio Dynamics Corporation in New Milford, CT in the early 1960's. His original ADC-1 ("Tip mass: 0.6 mg. Compliance. 20x10–6cm/dyne, all directions. Playing weight: 1 gram or less in top quality arms") was a breakthrough product. Indeed, all ADC pickups were notable for their extremely high compliance and low tracking forces and he pursued this approach through a series of successful designs including the well-known ADC-10,…
The video for Colin Stetson’s “The Stars in His Head” (Dark Lights Remix), directed by Isaac Gale and Dan Huiting. Kinda lovely, kinda creepy, kinda perfect for this chilly, gray day.
Colin Stetson's powerful record, New History Warfare, Vol.2: Judges, available from Constellation Records, was reviewed in the July 2011 issue of Stereophile.
Zola Jesus - Seekir by sacredbones
Here’s a new track from Zola Jesus’ upcoming record, Conatus, to be released by Sacred Bones Records on October 4. The track is called “Seekir” and suggests a more polished sound for Miss Nika Rosa Danilova. Combining elements of goth, industrial, pop, opera, and noise, Danilova seems to still be searching for her voice, which is exactly as it should be for a 22-year old with an extremely promising future.
Let her keep searching. I'll follow wherever she goes.
KEF and I go way back. As a very young man in the 1960s, I was obsessed with building speakers, and that was just about the time that KEF founder Raymond Cooke was revolutionizing driver design by using new synthetic materials for cones and surrounds, and experimenting with such innovations as transmission-line–loaded midrange drivers. I found it all very heady and, by direct import from the UK, obtained versions of the oval, flat-diaphragm B139 woofer, the Bextrene-coned B110 and B200 woofers, and the T-15 and T-22 dome tweeters. Fifty years ago, this was all cutting-edge speaker technology…
I usually begin with vocal recordings because a) a good loudspeaker will permit the listener to make a human connection with a realistically reproduced human voice, and b) voices make me focus on the midrange, the part of the audioband that conveys most of the musical information provided by instruments and voices alike. In this regard the Q900 was remarkably good, reproducing a wide range of male and female voices with presence, and with no spatial distinction between fundamentals and sibilants. Solo voices, including that of Sara K. on her Don't I Know You from Somewhere? Solo Live (CD,…
Sidebar 1: Specifications
Description: Two-and-a-half-way floorstanding loudspeaker. Drive-units (all aluminum): Uni-Q (coaxial) with 1.5" vented dome tweeter and 8" midrange unit, 8" woofer, two 8" passive radiators. Crossover frequency: 1.8kHz. Frequency response: 32Hz–40kHz, ±3dB. Impedance: 8 ohms. Sensitivity: 91dB/2.83V/m. Maximum output: 114dB. Amplification: 15–200W.
Dimensions: 41.7" (1060mm) H by 9.6" (244mm) W by 12.7" (322mm) D, without plinth; 43.6" (1107mm) H by 14.1" (359mm) W by 12.7" (322mm) D. with plinth. Weight: 48.7 lbs (22.1kg).
Finishes: Black Oak, English…
Sidebar 2: Associated Equipment
Digital Sources: Yamaha BD-A1000, Oppo BDP-83 universal Blu-ray players.
Preamplifier-Processors: Marantz AV-7005, Integra DTC-80.2.
Power Amplifier: Bryston 9B STT.
Loudspeakers: B&W 800 Diamond, Paradigm Studio/60; Paradigm Reference Servo-15 and Studio SUB 15 subwoofers.
Cables: Interconnect: AudioQuest Vodka HDMI, Kubala-Sosna Fascination balanced. Speaker: Kubala-Sosna Fascination. AC: Kubala-Sosna Emotion.
Accessories: APC S-15 power conditioner.—Kalman Rubinson
Sidebar 3: Measurements
I measured the KEF Q900's frequency response in the farfield with DRA Labs' MLSSA system and a calibrated DPA 4006 microphone. The Q900's voltage sensitivity is specified as 91dB/2.83V/m. My estimate was slightly lower, at 90dB(B)/2.83V/m, but this is still usefully higher than average. The speaker's impedance is specified as 8 ohms, but as fig.1 shows, the impedance drops to 4 ohms in the top octaves and to below 4 ohms in the lower midrange, reaching a minimum value of 3.17 ohms at 160Hz. There is also a combination of 5 ohms magnitude and –42° electrical phase…
John Atkinson nudged my ribs with an elbow. "Did you bring your Cornelius CD with you?" he whispered.
It was the 2010 Consumer Electronics Show, and JA and I were nearing the end of a dog-and-pony act expertly presented by Atlantic Technology's president, Peter Tribeman, touting a prototype of his company's new loudspeaker, the AT-1. JA and I had just heard about the finer points of the AT-1's new bass-venting technology, the Hybrid-Pressure Acceleration System (H-PAS), which was supposed to combine all the benefits and qualities of a transmission-line enclosure, horn loading, and sealed…