This is the Yamaha Natural Sound Integrated Stereo Amplifier, from the early 1980s (1980–1982), a model that combines modern aesthetics with a refined and transparent sonic character, true to Yamaha’s “Natural Sound” philosophy.
One of the highlights of this series is the excellent built-in phono preamplifier — quite advanced for the time. It offers a rare 6-position phono selector and the now legendary DISC DIRECT switch, which bypasses tone and balance circuits to send the signal directly to the amplifier section — delivering clean, uncolored analog sound straight from your LPs.
The sonic performance is detailed and clean, with a neutral tonal balance and pleasant dynamics, although the bass may feel slightly reserved compared to more vintage, warmer-sounding 70s amplifiers. For some genres or listeners, this might seem a bit lacking, but overall, the sound lives up to Yamaha’s tradition of transparency and realism.
A known weak point of this series lies in the sliding input selectors, which over time tend to cause issues or need cleaning — it’s now uncommon to find a unit where these don’t require attention.
Still, these are beautiful, powerful and elegant amplifiers, with a clean, spacious design and a sound that many enthusiasts still appreciate today for its honesty and subtlety.
A classic Yamaha piece from a transitional era in hi-fi — not warm, but natural, and all the better for it.
Power output: 100 watts per channel into 8Ω (stereo)
Frequency response: 20Hz to 20kHz
Total harmonic distortion: 0.01%
Damping factor: 55
Input sensitivity: 0.16mV (MC), 2.5mV (MM), 150mV (line)
Signal to noise ratio: 77dB (MC), 93dB (MM), 103dB (line)
Channel separation: 70dB (MM), 70dB (MC), 70dB (line)
Output: 150mV (line)
Dimensions: 435 x 133 x 365mm
Weight: 10.5kg
Year: 1980











