All DCC players and recorders are auto-reverse, so every player and recorder must have a way to position the heads for the A-side as well as the B-side of the tape. In stationary recorders, the mechanism switched sides by pivoting the head assembly 180 degrees (Philips used a modified version of an analog auto-reverse cassette deck during development, on which this mechanism was based), but in portable recorders and players, the head assemblies had heads for the tracks on both sides, which saved space in the mechanism, but made the head assembly more complicated: