I should mention that I reacted to the single-ended triode phenomenon with great skepticism. My…
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Although I'll be spending most of my time at Stereophile reviewing affordable gear, I will from time to time examine so-called "trickle-down" designs from high-end designers who have made their mark in the upper-price echelons. More and more, such designers are taking what they've learned and applying it to less-expensive products in order to broaden their customer base. Cary Audio Design, for example, of single-ended triode fame, has entered the ring with the SLM-100 pentode monoblocks.
The Cary's high-frequency reproduction was sweet and extended, but on certain recordings the transients could sound a bit slow. This occasionally made percussion sound a bit blunted, and highly modulated cymbal and gong crashes swished a bit. But this was a very subtle effect, and was less noticeable than with the original SLM-100, in production before the middle of 1994 (and which used a slightly different input stage and tube complement). The earlier model sounded noticeably sluggish on all material.
Bass reproduction could plunge convincingly into the nether regions, at least up to…
Sidebar 1: Specifications
Description: Push-pull, class-A, monoblock tube amplifier. Output power: 113W into 8 ohms (20.5dBW), 100W into 4 ohms (17dBW). Frequency response: 9Hz–30kHz, +0, –0.75dB, at 1W; 15Hz–23kHz, ±0.5dB, at full power. Input sensitivity: 750mV for full output. Input impedance: 150k ohms. Noise and hum: 80dB below rated output. Damping factor: >30, equivalent to an output impedance just above 0.3 ohms.
Dimensions: 6" H by 10" W by 20" D. Weight: 40 lbs.
Price: $3495/pair; optional chrome chassis adds $500/pair (1996); no longer available (2009). Approximate…
Sidebar 2: System
To audition the Carys, I utilized my Goldmund Studio/Syrinx PU-3 Revised/Koetsu Urushi and CAL Delta/Sigma II front-ends. Preamplification was via a Vendetta Research SCP-2C phono stage and Audible Illusions Modulus 3 and L1 line stages. Speakers were the Infinity RS-1Bs (amplified by a Perreaux 2150B amplifier below 100Hz), and the full-range Acarian Systems Alón 5 Mk.IIs. Comparison amplifier was the Audio Research Classic 60. Wires included MIT MI-350 Twin CVTerminator and MIT '330 Shotgun interconnects, MIT Digital Reference interconnect, MIT MH-770 Twin…
Sidebar 3: Measurements
Following its one-hour, 1/3-power preconditioning test, the Cary SLM-100 was typically hot for a tube amplifier. Its voltage gain into 8 ohms measured 26.7dB, the input impedance a high 123.6k ohms. DC offset was effectively zero. The SLM-100 was non-inverting, a positive-going input emerging positive at the output. The unweighted S/N ratio (ref. 1W into 8 ohms) was 77.4dB over both 22Hz–22kHz and 10Hz–500kHz bandwidths. A-weighting improved the figure to 90dB. Despite Cary's claimed high damping factor, the SLM-100's output impedance varied between 5.4 ohms and a…
In the name of journalistic ethics (footnote 1) I have to come clean. David Manley once gave me a gift. He presented me with a large, rather heavy, Russian-made watch at the 1995 Las Vegas WCES. A very manly watch: In fact, it said "Manley" right on the dial. The watch worked fine for about six months. Then it developed a very subjective approach to timekeeping. Time stood still, and my life wasn't even passing before my eyes. The watch has become a nice, albeit slightly ugly, mini–boat anchor; now my rubber ducky stays where I put it in my bathtub.
Giving someone a present is…
The Soft-Start setting also protects the amplifier against brownouts. Unlike most tube amps, whose owners often leave them on permanently to insure optimum performance, the Manley 240 can be left in Soft-Start mode. Then, if your local power company decides to brownout (suddenly dropping the voltage), the subsequent surge should do no damage. In an amplifier with a regular standby mode, such surges may damage components, since all but the B+ rail is still fully powered.
The Manley's Soft-Start setting is not the same as a mute. Not only will music still play through the Reference 240…
When listening for pleasure, I usually select the triode switch on the Reference 240s. Combined with a warm fire, a glass of brandy, and my beloved, the Manleys in triode mode can instill a sense of well-being and cosmic contentment that banishes even the most exasperating daily frustrations. If, on the other hand, I need to know what is really going on in a mix, or I'm wearing my reviewer's cap (the one with the big Mickey Mouse ears), I flip the Manleys into tetrode mode. For full orchestral recordings and "serious" rock and roll at "realistic" levels, tetrode is obviously the way to go.…
Sidebar 1: Specifications
Description: All-tube monoblock power amplifier with class-AB, push-pull output stage. Output power (at 1.5% THD): 240W into 5 ohms (21.8dBW) (tetrode mode); 100W into 5 ohms (18.0dBW) (triode mode). Input impedance: 100k ohms. Output impedance: transformer secondary set to 5 ohms. S/N ratio: 80dB. Input sensitivity: 1V for full output. Power consumption: 30W, standby mode; 815W at full power.
Dimensions: 19" W by 11" H by 13" D. Weight: 63 lbs each.
Serial numbers of units tested: R24025 & R24026.
Price: $9000/pair (1996); no longer available (2009…
System
For this amp review the following equipment was used: Analog sources were a VPI TNT Jr. turntable, with cost-effective upgrade and outboard flywheel, on a Bright Star base and a Townshend Seismic Sink. Tonearms were the Graham 1.5T/C, and Clearaudio/Souther TQ-1. In my small room, a VPI HW-19 Mk.IV with a SAMA and mounted with a Clearaudio/Souther TQ-1 sits on a Bright Star J-7 base. Cartridges included the van den Hul MC-1 Super, Dynavector XX-11, AudioQuest MC-200, Fidelity Research/van den Hul FR-1, Denon 103/van den Hul, and Denon DL-S1. Digital front-ends were PS Audio…