Because it came up recently, here's an aural comparison of the 8 and 16-bit compression options available in DOS for the SB16 architecture. Hooray.

• 16-bit LPCM Reference File

- Format: 16-bits per sample STEREO 44.100 kHz PCM
♫PCM.WAV (5.22 MB)
♫Recorded CT3980 playback (FLAC)

• 16-bit Compressed Formats (CSP required for hardware decompression)

- Format: 8-bits per sample STEREO 44.100 kHz CCITT ALAW
♫ALAW.WAV (2.61 MB)
♫Recorded CT3980 playback (FLAC)

- Format: 8-bits per sample STEREO 44.100 kHz CCITT MULAW
♫MULAW.WAV (2.61 MB)
♫Recorded CT3980 playback (FLAC)

- Format: 4-bits per sample STEREO 44.100 kHz CTADPCM
♫CTADPCM.WAV (1.30 MB)
♫Recorded CT3980 playback (FLAC)

• 8-bit LPCM Reference File

- Format: 8-bits per sample MONO 10.989 kHz PCM
♫PCM.VOC (334 KB)
♫Recorded CT3980 playback (FLAC)

• 8-bit Compressed Formats

- Format: 4-bits per sample MONO 10.989 kHz 8-4 ADPCM
♫ADPCM_4.VOC (167 KB)
♫Recorded CT3980 playback (FLAC)

- Format: 3-bits per sample MONO 10.989 kHz 8-3 ADPCM (2.6-bit)
♫ADPCM_3.VOC (111 KB)
♫Recorded CT3980 playback (FLAC)

- Format: 2-bits per sample MONO 10.989 kHz 8-2 ADPCM
♫ADPCM_2.VOC (83.6 KB)
♫Recorded CT3980 playback (FLAC)

Couple of notes:

A-Law, µ-Law, and CTADPCM are the only 16-bit compression types supported by the DOS-based CSP Manager - the playback of which requires a CSP chip. By comparision, these and additional compression types are available in Windows, as both hardware-based CSP code/algorithms and software-based Microsoft Audio Compression Manager CODEC modules. In other words, and compared to DOS playback, a CSP is not required for playback in Windows environments where MSACM is available (with a corresponding CPU cost), but is still used when present.

8-bit ADPCM compression is limited to 8-bit mono samples, with rates constrained to 4000 - 12000 Hz (8-4), 4000 - 13000 Hz (8-3), and 4000 - 11000 Hz (8-2). All ISA-based Sound Blaster cards can decompress these formats with no additional hardware, while the compression is handled in software.

Assuming proper hardware and software configuration, all of the referenced WAV and VOC files can be played in DOS using Creative's "Play" utility.

Finally, the 8-3 and 8-2 ADPCM formats are obviously ill-suited for general music playback, but work well enough for speech and explosion sound-effects (not demonstrated).