Sony SB-200 1970s

This device turns a 3-head reel-to-reel tape recorder into a tape echo machine. Best realized with a 3-speed tape recorder. The volume control can create run away feedback. Interesting effects are created when recording with echo at a higher speed, then playing back at a lower speed. Also has sound-on-sound function, allowing users to record new audio onto a tape while simultaneously playing back previously recorded tracks, effectively layering sounds in real time on just 2 channels of sound. For example, sound already recorded on the left channel is dubbed onto the right channel along with new sound being added. This can be repeated recording the right channel onto the left with additional sound added.