The Onkyo TX-SV7M is said to be the first Dolby Surround A/V receiver sold in the U.S. and Canada, way back in the all-analog days of 1987. Dolby Surround was the consumer version of the theatrical Dolby Stereo format that was used in movie theaters in the 1980s. Dolby Surround soundtracks were matrix-encoded into stereo formats such as VHS tapes, Laserdiscs, etc. The TX-SV7M was a four-channel receiver, with front left, right, and two surround channel amplifiers (the surrounds were monophonic). The .1 (LFE) channel wasn’t yet part of the home theater setup. It’s a bit of a mystery as to why Onkyo finally got around to making a Dolby Surround receiver in 1987, when the format was 5 years old, and more confusing because Dolby Pro Logic debuted the same year as the TX-SV7M. Pro Logic also used mono surround channels but offered improved steering and localization cues with Dolby Surround–encoded Laserdiscs and VHS tapes. Power output was specified at 90 watts per channel for the front left and right channels and 20 watts per channel for the surrounds. The receiver’s features set also included an MTS (multichannel television sound) processor. The Onkyo receiver retailed for $1,000, and that was a lot of money 25 years ago!

While the TX-SV7M was made in Japan, it was strictly an export model for the North American market. Japanese audiophiles had little interest in receivers and preferred integrated amplifiers. I was also surprised to learn the TX-SV7M wasn’t the flagship model in the Onkyo receiver line. It was far from it, in fact. Those were the days of high-powered stereo receivers, and all of the major Japanese manufacturers put their energy into making the very best-sounding stereo receivers. It didn’t take long for that situation to reverse, and the receiver manufacturers embraced the home theater market.

(Thanks go out to AudioReview.com for the use of the TX-SV7M picture, and for information from Onkyo’s product manager for the U.S. at the time, David Birch-Jones.)