ACID 64 is developed by Wilfred Bos and is a cycle based Commodore 64 music player designed for playing SID tunes on sound cards/devices that have a real SID chip (6581/6582/8580) on board.
In version 2.3 the following has been improved: SID reset. Numeric keypad can now be used for short cuts. Added features are: Voice 4 mute/undo mute short cut. Popup menu for selecting sub tunes. Fixed in this version are: Digi playback on ISA/PCI cards has no more timing problems. Window size and position startup option is now shown correctly.