Flexibility and Beauty: Audio Research's Reference 80S
udio Research's new Reference 80S ($15,000) is a fully balanced differential stereo amplifier that uses two matched pairs of KT150 output tubes to deliver 70Wpc. The amp's four-layer circuit board is said to "provide a separate ground plane, better circuit layout, and fewer noise-inducing point-to-point connections." Like other recent Audio Research amplifiers, the Reference 80S has features not found on many other tube amps. Its proprietary auto-bias circuit adjusts for tube age as well as voltage changes from the power line. An hour meter -- "like an odometer for your amp" -- lets the user know how many hours the tubes have been in use. Switchable triode/pentode operation accommodates different loudspeakers and different listeners, but Audio Research touts the Reference 80S as "a tube amplifier that does not require fiddling, it is meant to be enjoyed." Connection flexibility is also part of the Reference 80S's feature set: there are XLR and RCA inputs, along with 4-, 8- and 16-ohm output taps. Other user-definable options are switchable fan speed and a defeatable auto-off function. Unlike Audio Research amps of the not-too-distant past,
with their recognizable laboratory-grade aesthetics, the Reference 80S is understatedly
beautiful. A final choice for the user is the amp's finish -- either silver or black. |
