But Bryston's Chris Russell decided that the 9B-THX required more than a reshaped…
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The 9B-THX is derived from Bryston's 3B-ST, reviewed positively in these pages in October 1996 (Vol.19 No.10). The modules' design was further developed, in Bryston's PowerPac series, as a 120W ($795) amplifier mounted on a flat plate that could be attached to the back of a speaker to make it a powered monitor. For the 9B-THX, this single-channel amp was transformed into a thin, 17"-long plug-in card. The card's length keeps the front power supply a good distance from the rear input stages, to minimize hum.
The ground trembles with its force
Following a steady stream of massive two-channel audiophile amplifiers, the relatively compact Bryston 9B-THX spelled relief for this reviewer. During my auditioning, I placed it atop a Mark Levinson No.334 stereo power amplifier. Rated at approximately the same power, the Levinson was 1.6 times as expensive, almost 1.5 times as heavy, just as deep, twice as tall, and yet had three fewer channels! For someone used to doing the audiophile amplifier-lift—deep breath, bend at the knees, lift straight up to protect the back—moving the 9B-THX's 75 lbs…
Following a steady stream of massive two-channel audiophile amplifiers, the relatively compact Bryston 9B-THX spelled relief for this reviewer. During my auditioning, I placed it atop a Mark Levinson No.334 stereo power amplifier. Rated at approximately the same power, the Levinson was 1.6 times as expensive, almost 1.5 times as heavy, just as deep, twice as tall, and yet had three fewer channels! For someone used to doing the audiophile amplifier-lift—deep breath, bend at the knees, lift straight up to protect the back—moving the 9B-THX's 75 lbs…
Sidebar 1: Specifications
Description: Five-channel, solid-state, power amplifier. Output power into 8 ohms: 120Wpc (21dBW), 20Hz-20kHz, 0.5% THD (FTC). Output power into 4 ohms: 200W minimum continuous (23dBW). Frequency response: not rated. THD+noise: 0.007%, 20Hz-20kHz, ±0.1dB. Intermodulation distortion: 0.002%, 60Hz+7kHz mixed 4:1. Noise: -107dB, input shorted, dB below rated output, 20Hz-20kHz bandpass. Input impedance: 15k ohms, balanced or single-ended. Input sensitivity: balanced input regular, 2V in for 100W into 8 ohms; balanced input in +6dB switch position, 1V in for 100W…
Sidebar 2: Welcome to the Real World
Watching The Matrix over the home-theater system I used to review the Bryston 9B-THX was a kick. The sound was highly dynamic, extended, and effortless, and the visual action was non-stop. Laurence Fishburne, who plays the prophetic leader, Morpheus, says, "Welcome to the real world" after the hero, played by Keanu Reeves, undergoes a rigorous education that teaches him a new way of thinking. Neo was re-educated the Hollywood way: kicked, stomped, tossed against walls, shot at, and thrown off buildings. While not as vigorous, my multichannel education…
Sidebar 3: Associated Equipment
Analog source: Linn Sondek LP12 turntable with Lingo power supply, Linn Ittok tonearm, Spectral moving-coil cartridge.
Digital source: Krell MD-1 CD transport, Theta Carmen and Denon DVM-3700 DVD/CD players, Lexicon MC-1 Controller.
Tuners: Day-Sequerra FM Reference Classic; Rotel RH-10; Magnum Dynalab MD-102, 205 Sleuth RF amplifier.
Preamplification: Krell KBL preamplifier, Mark Levinson ML-7A preamplifier with L-2 phono section, Duntech MX-10 moving-coil preamplifier.
Power amplifiers: Mark Levinson No.334, Bryston 7B-ST monoblocks, Denon A/…
Sidebar 4: Measurements
The five-channel Bryston 9B-THX is the first multichannel amplifier I've measured for Stereophile, so I had to scramble a little to get five identical dummy loads. Even then, the Audio Precision System One I use can measure only two channels at a time, so I generally looked at just one channel. However, for the power testing I did drive all five channels for the 8 ohm measurement, and two for the 4 ohm result. Although the 9B has a tip-ring-sleeve balanced input connector for each channel, I tested it only using its singled-ended RCA inputs. I also didn't measure…
Even with all five channels driven, the 9B-THX more than met its 120Wpc output power specification, the left-hand trace in fig.7 revealing that it put out approximately 160W (22dBW) into 8 ohms at our standard 1% THD+N clipping point. I didn't have enough high-power resistors to simultaneously test all five channels into 4 ohms, but with two channels driven, 260W (21.1dBW) was available (right-hand trace). (Ignore the sawtooth effect in this graph. With the very low distortion and noise offered by the Bryston, these discontinuities in the traces are due to the Audio Precision's automatic…
I have a passion for great speaker designs at affordable prices, and with modern driver, crossover, and cabinet technologies making innovative strides, many serious high-end speaker designers are turning their attentions to coming up with the next great budget speaker. All audiophiles need affordable speakers, whether to recommend to friends to lure them into our hobby or to set up multiple, less costly systems in our own houses. I currently run a main reference system, a vacation-house system, a recording-studio system, a computer system, a portable system I take to parties, a car system,…
Rock vocals were reproduced equally nicely. Thurston Moore's forward and breathy baritone on Sonic Youth's ballad, "Hits of Sunshine" (A Thousand Leaves, My So Called Records 03)—the best-recorded male vocal on a rock record I've ever heard—was captured in its intimate and dynamic splendor.
This speaker loved woodwinds. Those instruments whose registers dominate the upper-bass/lower-midrange regions sounded especially natural, detailed, and tactile, most notably the clarinet passage in the opening segment of my audiophile acid test, Kohjiba's The Transmigration of the Soul (Festival,…
Party Speakers!
Dynamics were another strong suit of the Image 4T—the aforementioned Stravinsky, Wuorinen, Peer, and Sonic Youth recordings kicked major butt at higher volume levels. In fact, the 4T's high-level dynamic performance exceeded that of any speaker I'd previously heard costing anywhere up to $1000/pair.
Dynamics were another strong suit of the Image 4T—the aforementioned Stravinsky, Wuorinen, Peer, and Sonic Youth recordings kicked major butt at higher volume levels. In fact, the 4T's high-level dynamic performance exceeded that of any speaker I'd previously heard costing anywhere up to $1000/pair.
The 4T's combination of bass and dynamic capabilities made it a great rock speaker. Unfortunately, I got a bit carried away demonstrating these strengths: When I cranked up Hole's Celebrity Skin (Geffen DGCD-25164, CD) and King Crimson's Thrak (Virgin 8 40313 2, CD) to…