The Onkyo SC-660 is a floorstanding loudspeaker that was manufactured from 1986 to 1988 in Japan. It features a three-way design with a bass reflex configuration. The speaker has a 220 mm cone woofers constructed from Deltaolefin II material for robust low-frequency response, accompanied by a 120 mm midrange driver made from cross carbon, and dual 25 mm titanium dome tweeters for high frequencies. With a nominal power handling of 100 watts and a musical power capacity of 200 watts, it provides an efficiency of 89 dB per watt per meter, making it suitable for a variety of audio applications. The frequency response ranges from 33 Hz to 45 kHz, with key transitional ranges set at 280 Hz and 2,000 Hz. The Onkyo SC-660 has a 4-ohm impedance, allowing it to be paired with a wide range of amplifiers. The cabinet is available in walnut and black finishes and features removable fronts for aesthetic versatility. Its dimensions are 292 mm wide, 580 mm high, and 297 mm deep, and it weighs approximately 15.5 kg. At launch, the speaker was priced around 750 DM.
