Tesla Sonet B3

Improved successor to the Sonet Duo, retaining the same robust transport and two-speed operation but adding a 7-inch reel capacity, a 4-digit tape counter, a more powerful 2.5-watt amplifier and improved frequency response and wow-and-flutter figures over its predecessor. Quarter-track mono recording, with stereo playback possible via an external amplifier. Valve (tube) indicator lamp resembling a 'magic eye'.