ToneMatch®
What is the concept behind ToneMatch™ presets, and what are the benefits?
ToneMatch™ presets make it easy to get exceptional amplified tone from any voice or instrument when used with Bose® L1™ portable line array systems. When you select a proprietary ToneMatch preset for your microphone or instrument, you are tapping into a powerful new technology available only from Bose. A skilled studio engineer listened to the sound of your instrument being played through an L1 system, made adjustments to improve the sound quality and then saved those settings as a ToneMatch preset.
Now the high level of tone customization that most musicians experience only in a recording studio is available on stage at your live performances. Sound check can be as simple as plugging in your instrument or microphone and selecting the appropriate ToneMatch preset.
-- Source: Bose® L1™ Model I FAQ
Note: There is a recent video of Ken Jacob describing ToneMatch™. I am trying to locate it so we can put it here. Here is a shorter version from the days before we called Presets, ToneMatch™ Presets.