TECHNICAL SPECIFICATION
POWER OUTPUT
75 watts per channel continuous from 20Hz to 20kHz. 1kHz total harmonic distortion typically 1% at 75 watts, below 0.05% at 1 watt. (Note that actual 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.)
POWER BANDWIDTH
(-3dB points) 7Hz to 60kHz.
FREQUENCY RESPONSE
(-3dB points at 1 watt) 0.7Hz to 80kHz.
INPUT SENSITIVITY
1.4V RMS BAL for rated output. (25dB Bal gain into 8 ohms.)
INPUT IMPEDANCE
300K ohms Balanced (150K ohms SE)
OUTPUT POLARITY
Non-inverting. Balanced input pin 2+ (IEC-268)
OUTPUT TAPS
8 ohms, 4 ohms
OUTPUT REGULATION
Approximately 1.0dB 8 OHM LOAD TO OPEN CIRCUIT (Damping factor approximately 8)
OVERALL NEGATIVE FEEDBACK
15dB
SLEW RATE
10 volts/microsecond
RISE TIME
4.0 microseconds
CHANNEL SEPARATION
112dB
HUM & NOISE
–112dBV no signal, input shorted
SIGNAL TO NOISE
115dB
CONTROLS
Power on/off, auto shut-off on/defeat, Input BAL/SE, RS232, 12V trigger
AMBIENT AIR TEMPERATURE
30° C (86° F) maximum ambient air temperature
POWER SUPPLY ENERGY STORAGE
Approximately 350 joules
POWER REQUIREMENTS
100-125VAC 60Hz (200-250VAC 50Hz) 410 watts at rated output, 500 watts maximum, 230 watts idle. Sleep power < 1 watt
TUBES REQUIRED
2 – Matched pair KT120 – Power Output; 2 – 6H30 Driver
DIMENSION
width 19” (48.3 cm)
height 10.33” (26.2 cm)
depth 18.45” (46.8 cm) to chassis , 19.40” (49.3 cm) to terminals
WEIGHT
45.7lbs. (20.7 kg) Net; 60.5 lbs. (27.4 kg)
Audio Research VT80
Absolute Sounds is pleased to introduce the VT80 vacuum-tube power amplifier to its Foundation Series. From the same design and engineering team responsible for the award-winning Reference Series, the VT80 allows the Foundation Series to be shown as
a complete system. Combining an enticing new aesthetic with worry-free operation and great performance, the VT80 is a vacuum-tube amplifier that will make Audio Research accessible to a larger group of music lovers. The U.S. retail price is $8,000.00 in North America; the retail price is $8,500 outside of North America because those units are supplied with a CE-compliant ventilated tube cover. With its beautiful new look, flexible connection options and important new features, the primary goal of the VT80 is to provide an incredible musical experience. The core of the
VT80 is adapted from the Reference 75, including the same power and output transformers, a similar circuit topology, and many of the same parts. The result is breathtaking and provides a new sonic reference in its price range.
Two important new features never before offered by Audio Research are at the heart of the VT80. The first is a proprietary auto-bias circuit developed entirely in-house by Audio Research’s chief analog engineer. Once the tubes are installed and the unit is poweredup, the VT80 will automatically adjust bias for each output tube. The circuit adjusts for tube wear or fluctuations in the power in real time and does not compromise performance. The VT80 will also work with different types of output tubes, including
6550, KT88, KT90, KT120 or KT150. The second new feature includes individual fusing of each output tube. In case of a fault condition, a replaceable fuse blows, providing worry-free operation. The 75 watt-per-channel VT80 is a balanced design that provides startling dynamics, powerful bass, and natural clarity combined with a very holographic presentation. The open architecture of its extruded metal chassis provides beauty and a rigid structure from which two 6H30 driver tubes and four KT120 output tubes emerge. Available in both natural and black anodized finishes, the low profile front panel contains a black inlay that matches other Foundation Series products, along with a power switch, flanked by two handles.
The rear panel contains both single-ended RCA and balanced XLR input connectors that allow the VT80 to be integrated into virtually any system. In addition to a tube hour meter, there is a 12V trigger and an RS232 port to remotely control operation. 4- and 8-ohm gold over brass binding posts provide secure speaker connections. There is also a switch to engage or defeat an auto-off function, triggered when no input signal is encountered after two hours.
