The Reference 80S stereo amplifier continues Audio Research’s latest design effort in creating a vacuum-tube amplifier that not only redefines ultimate music reproduction, but does it in an incredibly beautiful package.
 
The 80S was created for the music lover who does not require the output power of its larger siblings, the Reference 160S stereo and 160M mono amplifiers. The 80S continues the design ethos, including dual GhostMeters® that float in front of four KT150 output tubes. Extruded panels, a vital part of the all-aluminum chassis, provide rigidity and beauty.
 
Outwardly, the 80S shares the same dimensions as the 160M. A single shallow whisper fan is built into the bottom plate. Flexibility is built-in, too, with XLR and SE inputs, 4-8-16 ohm output taps, 12V input and output triggers, RS232 input, tube hour meter, switchable fan speeds, and defeatable auto-off function.
The feature set is the same as the 160S, including a proprietary auto-bias circuit that adjusts for not only tube age, but for powerline voltage swings. There is fusing of the output tubes, single-ended and balanced inputs for flexibility, switchable Triode-Pentode operation to accommodate loudspeakers and personal preference, output tube monitoring, and inclusion of an hour meter so you know how many hours are on the tubes–like an odometer for your amp. This is a tube amplifier that does not require fiddling, it is meant to be enjoyed. The built-in 12V trigger turns the 80S on or off when connected to a modern preamp with a 12V trigger. 
 
Like every Reference amplifier before it, the 80S is a fully-balanced differential design because it provides the highest performance and lowest distortion. A four-layer circuit board is used to provide a separate ground plane, better circuit layout, and fewer noise-inducing point-to-point connections. Music is projected against a quiet, jet-black background—like looking at the stars out in the country, removed from light pollution. It is magical and enveloping.
 
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