Hitachi SR 903

I’ve always liked Hitachi. Often overlooked in hi-fi conversations dominated by the likes of Sansui, Marantz, Pioneer, or Kenwood, Hitachi quietly built some absolute masterpieces—and the SR-903 is one of them.

Released in 1977, the SR-903 is a solid, well-built receiver known for its clean design and excellent sound performance. It preceded the SR-904, which brought some cosmetic updates like VU meters. While those meters are cool, I personally prefer the classic 1970s look of the SR-903, especially with its solid aluminum knobs.

This unit is large and robust, delivering strong and dynamic audio:

• Rated at 75 watts per channel RMS, but thanks to Hitachi’s Class-G topology (called “Dynaharmony”), it can boost power output up to 160 watts per channel during musical peaks without distortion.

• It uses a 3-rail voltage system, a technique that few manufacturers mastered, resulting in better dynamic headroom and clean, controlled sound.

• The sound is detailed and fast, with tight bass, crisp highs without harshness, and a natural, musical midrange.

Internally, almost every component is Hitachi-made, except the filter capacitors. The transformer is massive, and there’s an impressive number of discrete transistors, reflecting the company’s engineering expertise at the time.

As Stereo Magazine noted:

“It can produce a little more than 3 dB above rated power – twice its continuous wattage rating on transient peaks without clipping, rivaling many superamps… performance far exceeds what can be expected from a conventional 75-watt amplifier.”

The SR-903 is an underrated gem. If you find one in good condition, it’s definitely worth a listen and could compete with many more famous vintage receivers.