[Kaleb.G]

It's not much of a mystery so much as an ambiguity.

Sonic the Hedgehog 3: http://youtu.be/eixeGTp9sOM?t=5m48s

Composers:

Music Composers
Brad Buxer
Bobby Brooks
Darryl Ross
Geoff Grace
Doug Grigsby III
SCirocco

Sega Sound Team
Bo
Sachio Ogawa
Milpo
Masaru Setsumaru
Tatsuyuki Maeda
Tomonori Sawada
Masayuki Nagao
Jun Senoue

Sound Project Coordinator
Hisaki Nimiya

Most of those composers are music producers for Michael Jackson.

Sonic & Knuckles: http://youtu.be/dUMl9gxxaBM?t=5m28s

Composers:

Music Composers
Howard Drossin

Sega Sound Team
Bo
Sachio Ogawa
Milpo
Masaru Setsumaru
Tatsuyuki Maeda
Tomonori Sawada
Masayuki Nagao
Jun Senoue

Sonic 3 & Knuckles

S3 ending version 1: http://youtu.be/eKUlDL4Dn5c?t=6m
(no credits)

S3 ending version 2: http://youtu.be/Expe5CcM30s?t=7m35s
(same as Sonic the Hedgehog 3)

S&K ending: http://youtu.be/5lL6E8xLiUk?t=2m43s
(literally a combination of the two games)

Composers:

Music Composers
Brad Buxer
Bobby Brooks
Darryl Ross
Geoff Grace
Doug Grigsby III
SCirocco
Howard Drossin

Sega Sound Team
Bo
Sachio Ogawa
Milpo
Masaru Setsumaru
Tatsuyuki Maeda
Tomonori Sawada
Masayuki Nagao
Jun Senoue

Sound Coordinator
Hisaki Nimiya

Also, check out this:
http://www.mtv.com/news/articles/162...undtrack.jhtml

Like how VGMdb is linked on the MTV website? ;}