It’s logical to start any discussion of drum mapping with the one established standard-the General MIDI (GM) Drum Map. This brings up a number of issues, which this article will take a brief look at. While there is a standard for this, it’s not universally used, and different drum instruments often utilize different arrangements of drums across the keyboard. But since the individual drum and cymbal samples in a virtual kit are un-pitched, key assignments are made at the discretion of either the person designing the patch, or the end user.

With other sample-based instruments, the mapping is, of course, based on pitch-the individual samples are assigned to Root Keys that correspond to the notes on the MIDI keyboard that match the actual pitches sampled. Virtual drum instruments present a unique consideration-how to map the drums across the keyboard for live playing of drum parts.