Tube mono power amplifier. Two versions exist: VT150 and VT150SE (Special Edition).
Power amplification in a new key. The VT150 Special Edition mono-blocks and VT130 Special Edition stereo amplifier represent the latest advancements in vacuum-tube power amplification from legendary designer William Z. Johnson. Both models take advantage of breakthroughs in transformer lamination and improved plate coupling to yield wider bandwidth, better power transfer at the output, and superb bass control. They also combine meticulous engineering and manufacture (typical of Audio Research), generous power output and user convenience in classically handsome electromechanical packages. These are power amplifiers intended to withstand the rigors of musical playback over the course of many years, while providing unequalled enjoyment.
The buyer's only dilemma is the choice between the ultimate soundstaging and musical dynamics made possible by the dual-monoblock approach, or the space-saving (but sonically remarkable) single-chassis stereo design. Both models are housed in incredibly rugged, heli-arc welded and anodized aluminum chassis more typical of aircraft construction than of typical hi-fi gear. Both models afford excellent performance with a wide variety of contemporary loudspeaker designs, and offer a range of output impedance options via their rugged, custom-machined terminal connections.
Output-stage biasing is easily maintained in both models by illuminated meters and rotary controls conveniently located on the front panel. A.C. powerline monitoring is also offered via a second meter.This means that the owner can effectively bias the output stage of the amplifier(s) depending upon A.C. line conditions as well as regularly monitor the condition of individual output tubes. All in all, it's a convenience which actually helps keep performance at absolute peak month-to-month, year-to-year.
Standard versions: Beauty to charm the ear and becalm the budget. The VT150 monoblocks and VT130 stereo amplifier are each available in less-costly standard versions which offer near-equivalent performance at lower cost. Lacking are the cosmetic enhancements, and, in the case of the VT130 stereo, the front-panel biasing system and A.C. monitoring found on the "SE" version. The VT150 monoblock retains the biasing system with a smaller meter, but lacks A.C. monitoring. Chassis grade, input and output connectors, and internal level of finish are equivalent or identical in both standard and SE versions.
MSRP (US new retail)
|Power output||130 watts continuous at 16 ohms from 20Hz to 20kHz with less than 1.0% total harmonic distortion (typically below .05% at 1 watt). Approximate actual power available at "clipping" 145 watts (1kHz)|
|Power bandwidth||(-3dB points) 12Hz to 80kHz|
|Frequency response||(-3dB points at 1 watt) 2Hz to 200 kHz|
|Input sensitivity||2.3V RMS balanced for rated output|
|Input impedance||200K ohms balanced|
|Output regulation||Approximately 0.5dB 16 ohm load to open circuit|
|Overall negative feedback||15 dB|
|Slew rate||17 volts/microsecond|
|Rise time||2.0 microseconds|
|Hum & noise||Less than 0.5mV RMS (98dB below rated output, IHF weighted, input shorted)|
|Power supply energy storage||420 joules|
|Power requirements||110-125VAC 60Hz (220-250VAC 50Hz) 470 watts at rated output, 600 watts maximum, 290 watts at "idle"|
|Tube complement||(2 matched pairs) 6550, (2) 6550 regulators, (1) 12AX7 regulator amplifier, (4) 12BH7A driver, (2) 6922 input|
|Dimensions||VT150: 141/2" (37 cm) W x 12" (30.5 cm) H x 22" (56 cm) D. Knobs extend 5/8" (1.6 cm) forward. Output connectors extend 1" (2.5 cm) to the rear|
|VT150SE: 15.5" (39.4 cm) W x 10.9" (27.7 cm) H [10.5" (26.7 cm) panel + .4" (1 cm) feet] x 22.75" (57.8 cm) D behind panel, including rear handles. Front handles extend 1.5" (3.8 cm) forward of .38" (1 cm) thick panel|
|Weight||VT150: 62 lbs. (28.2 kg) Net; 82 lbs. (37.3 kg) Shipping.|
|VT150SE: 77 lbs. (35 kg) Net; 97 lbs. (44 kg) Shipping.|