It is a musical patch for "the jabu"'s improvement of NES Sonic (aka Somari).
All music tracks are replaced with their better versions created in famitracker.
Written by Amilgi without usage of extra audio chips and dpcm channel.
Some of sound effects changed too.
Patch applies (AFTER) for romhack : http://www.romhacking.net/hacks/3208/
Sonic The Hedgehog (NES) Improvement V1.0.nes
CRC32: B9353974
MD5: EC76FA5A331B6B066D56FEB162E014FF
SHA-1: C4734F522D038523E4EA094C1D0D44A142AFA188