Computer-Based Sequencers

Sequencers also are available as software packages that use the personal computer for performing central processing, memory, and I/O (input/output) functions. These systems are often powerful and extremely versatile in their speed, digital signal processing capabilities, memory management, and their capability to perform a diverse range of tasks under software control.

As you might expect, sequencing software is available for most Apple and IBM compatible machines. The majority of these computers require an external MIDI interface that is used for receiving and distrubuting MIDI data.

Computer based sequencers have several advantages over their hardware-based counterparts. One of the strongest advantages is easy visibility and access to both basic and advanced editing functions, resulting from the PC’s extensive DSP and graphics capabilities. Using standard cut-and-paste methods it becomes a simple matter to move a musical segment from one track to another, cut a musical passage from a song and save it to clipboard memory for later use, or copy a passage to a track. In addition, the large screen and established graphics interface style make it much easier to perform a complex function. Graphics pattern editing also lets the user quickly and easily change the pitch, start, and duration of times of a note as it appears on the screen (in a style known as piano roll editing), often through the simple movement of a mouse.

Because computer-based sequencers make use of the PC’s memory management capabilities, sequenced files can be easily stored onto either hard or floppy disks, while note capacity is usually restricted only by the PC’s amount of internal RAM.