"The VTM200 is an exciting new amplifier design for a number of reasons. First, it packs a strong 200 watts RMS output into a chassis size identical to the VT100MKII stereo. That means it can easily be tucked into a ventilated cabinet or behind a loudspeaker. Internal fan cooling is controlled by a two-speed switch on the rear panel. Output tube biasing is very user friendly, incorporating a simple rotary switch and large three-digit LED display on the back of the chassis. The system works by adjusting bias on just two of six 6550C output tubes, and checking bias level on the remaining four tubes. Input is XLR - only for best performance; output taps are provided for 4, 8 or 16-ohm speaker loads. We've even incorporated a 12V power -on.off trigger for custom-installation purposes.
Using classic vacuum-tube circuit design, the input stage of the VTM200 uses direct-coupled JFETs for ultra low noise. The input stage is followed by a single 6N1P vacuum-tube amplifying stage, which in turn is coupled to a pair of triode-connected 6L6GC tubes used as direct-coupled, cathode-follower drivers to provide exceptional linearity combined with good stability and service life. The output stage of six 6550 tubes is fed by a power supply with 438 joules of energy storage. Screen voltage for the partially cathode coupled output stage is supplied via two 6AS7 regulator tubes (in current production) driven by a 6N1P. The end result is an input/drive/output combination with incredible linearity and dynamic headroom, having great stability under dynamic conditions and varying speaker loads. The VTM200 should prove to be one of the most successful and popular Audio Research power amplifiers ever.
Sonically, the VTM200 has resolving power and musical dynamics which easily put it in the Reference class. Bass response is fast and powerful - here's where the big, linear power supply shows its mettle! Staging is extremely well-focused, layered and naturally proportioned. In fact, the VTM200 likely sets a new standard in its class with its ability to spatially replicate a good recording. With power, richness of body and an uncanny ability to resolve small textural and harmonic detail, the VTM200 is the kind of amplifier that demands to be driven by a current-generation Audio Research preamplifier."
[From the ARC website]
200 watts per channel continuous from 20Hz to 20kHz. 1kHz total harmonic distortion typically 0.5% at 200 watts, below 0.02% at 1 watt. Approximate actual power available at "clipping"; 210 watts (1kHz). (Note that actual RMS power output is dependent upon both line voltage and ‘condition’ i. e.: if power line has high distortion, maximum power will be affected adversely, although from a listening standpoint this is not very critical.)
(-3dB points) 10Hz to 200kHz
(-3dB points at 1 watt) 0.5Hz to 240 kHz
1.7V RMS Balanced for rated output. (27 dB gain into 8 ohms)
200K ohms Balanced
4, 8, 16 ohms
Approximately 0.6dB 16 ohm load to open circuit
Overall negative feedback
1kHz total harmonic distortion typically 0.5% at 200 watts, below .02% at 1 watt
Hum & noise
Less than 0.2mV RMS - 109dB below rated output (IHF-A weighted, input shorted, 16 ohm output)
Power supply energy storage
Approximately 438 joules
105-125VAC 60Hz (210-250VAC 50Hz) 670 watts at rated output, 850 watts maximum, 400 watts at "idle"
(3 matched pairs) 6550C power output, (1 matched pair) 6L6GC driver, (2) 6N1P gain stage and regular driver, (1 matched pair) 6AS7G regulator
19" (48.3 cm) W x 8 ¾" (22.2 cm) H x 19½" (49.5 cm) D. Handles extend 1½" (3.8 cm) forward
74 lbs. (33.6 kg) Net; 89 lbs. (40.4 kg) Shipping