The
esm device driver supports sound cards based on ESS Technology Maestro, Maestro-2, and Maestro-2E PCI AC97 Audio Accelerator chips (ES1968 and ES1978). Due to their power management capabilities, the Maestro chips are often used in laptop and notebook systems.
The Maestro is a full-duplex device that allows independent playback and recording at sample rates between 4000 Hz and 48 kHz. The sound processor is capable of handling and converting 8 and 16 bit mono and stereo data.