Sanyo C7

The Sanyo C7 is a boombox from the year 1981, but it's also a set of separate components. That's right, the tuner, tape deck, and power supply each have their own separate metal case. That's why it's very heavy for its size (11.2 kg, or 24.7 lbs, not including batteries). Each component is 215mm wide, and each speaker box is 140mm wide. Then there's a sturdy metal bracket that fits between them. In total, the system is 515mm wide, 232mm deep, and 307mm tall. In Japan, this system was known as the MR-C1. There were also two re-branded versions: Siemens RS-806 and Yamaha PC-9.

The service manual says its output power is 8 watts per channel RMS (maximum), into 2.5 ohms. The speakers include 10cm woofers (later upgraded to 12cm), and 4cm tweeters. Shown below is the supplement to the service manual, explaining that they upgraded the woofers from 10cm to 12cm sometime in the middle of its production cycle.