Akai GX-636 is a reel-to-reel tape recorder that was manufactured by Akai in the 1970s. It is a robust and well-built unit known for its high-quality audio playback. The GX-636 offers features such as three motor direct drive, auto-reverse, and dual capstan drive system. It supports various tape speeds including 3-3/4 ips, 7-1/2 ips, and 15 ips. The unit also includes features like Dolby noise reduction, adjustable bias control, and multiple inputs and outputs for connectivity.