Audio Research Reference 80S stereo power amplifier

REVIEW
Alan Sircom
Mar 29, 2022

OK, despite claims to the contrary, I’m going to cop to some ‘cheating’ of sorts. After I collated my notes on the Reference 80S, I went looking at both my reviews of its two bigger brothers and then looked at other reviewers’ work on all three amps. In truth, there’s some real consistency in all these words, as if the smaller, medium and larger models all have the same tonal characteristics (or at least, the same tonal characteristics relative to speaker and room size considerations). We’re all barking up the same dog (or something) here… and again I’m going to point to Warren Gehl’s adroit listening skills in fine-tuning these amplifiers to give them such consistency.

That consistency is the joy of this amplifier. If you have a yearning for Big Boy Audio Research, but don’t want or need the additional power and the increased size, space, heat and price tag that top-end amplification requires, the Reference 80S is perfect. Making a bigger amp smaller is often a path to being disgruntled, or at least puts you some way from being ‘gruntled’. This is the first step on the Audio Research Reference power amplifier ladder, and I can’t help but feel that while it is for many the only step they’ll ever need to take, for others the excellent Reference 80S will be the first step into a world of the highest in high-end audio.

TECHNICAL SPECIFICATIONS

Power output: 70 watts continuous from 20Hz to 20kHz
Tubes Required: 2 matched pair KT150 (Power output V1-V4); 2 6H30 (Gain stage V5, V6)
THD+N (@1kHz): typically 1% at 140 watts (33 watts in Triode mode) per channel, below 0.04% 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 critical)
Power Bandwidth (-3dB points):
7Hz to 68kHz
Frequency Response:
0.7Hz–94kHz (-3dB points at 1W)
Input Sensitivity: 1.4V RMS Balanced for rated output. (25.5 dB gain into 8 ohms); 0.7V RMS SE for rated output
Input Impedance: 300K ohms Balanced, 75K ohms Single Ended
Output Polarity: Non-inverting
Balanced input pin 2+ (IEC-268)
Output Taps: 16Ω, 8Ω, 4Ω
Output regulation: Approximately 1.0dB 16 Ohm Load to Open Circuit
(Damping factor approximately 8)
Overall negative feedback: 15dB
Slew Rate: 10 volts/microsecond
Rise Time: 4.0 microseconds
Dimensions (W×H×D): 48.3 × 26 × 47cm
Weight: 28.2kg
Price: £14,998