30 at this time turntable drive motor 82 rotates turntable 81 and disk 5 2 optical head 84 shown in fig1 is energized to read disk 5 2 and moved along optical head guide rails as it reads disk 5 2 when playback of disk 5 2 is complete optical head 84 is turned off and the rotation of turntable 81 is stopped controller 120 now causes clamp drive 125 to raise clamp arm 64 with shaft 68 disk 69 projection 70 and cylindrical clamp 71 to its start position at the same time controller 120 causes drive pin 53 to move back from lifter 40 allowing spring 54 shown on fig4 to pull lifter 40 back raising guide rails 49 to their start position causing subtray 23 2 to lift disk 5 2 off turntable 81 disk playback device 1 can now be operated to play another disk if an automatic play mode is selected the subtray select transfer and playback cycle is repeated until all or selected ones of the disks 5 1 5 6 stored in stacker 20 are played back referring to fig6 and 7 when a disk for example disk 5 1 is to be loaded into stacker 20.