It's no secret. Compared to the Super Nintendo, the Genesis wasn't exactly a killer in the sound department. It was fueled in part by what soundtracks really caught your ear, but for a real classic, you didn't have to look any farther than the Sega mascot.
Everyone's favorite hedgehog speedster has had quite a number of notable themes over the years which cements that, although the ride has been rocky with plenty of ups and downs, there's one thing that everyone can agree on, the music is nearly always awesome.
And you can now get a lot of this music on iTunes!
There may be many themes people and fans associate with the Blue Blur, but the Green Hill Zone is the definitive Sonic tune. Like Mario and the very first beats of the Mushroom Kingdom, the melody of Green Hill would make sure Sonic's music stuck around just as long as his rival's.
The Scrap Brain Zone theme (especially the first part) is one of the best tracks ever written to give the impression of "prepare for insane difficulty". Notably it, along with Star Light Zone, was reused as the music on the optionscreens for Sonic Advance. Furthermore, Scrap Brain Zone's theme, along with Green Hill Zone's music, were both included in Super Smash Bros. Brawl's awesome soundtrack.
The Sonic 2 Final Boss Theme. Quite possibly the most epic final boss battle in the series. (Though Sonic & Knuckles' (see below) certainly gives it a run for its money.)
The Death Egg Zone Theme is, for a 16-bit era track, an eerie, haunting piece of genius, with an undercurrent of madness. You normally only hear a couple seconds of it as you run to the right and face Silver Sonic, but if you stand there and wait for a little while you'll start getting thoroughly creeped out. Bonus points for the top melody sounding like some sort of deranged lullaby.
No variant on the boss music is complete without a reference to the realboss theme. Where the original game had its own unique flavor and Sonic 3 would later aim for straight-up intensity, this is too iconic to go unmentioned.
The Super Sonic theme in itself is almost enough incentive to get all the Chaos Emeralds. It's similar to the invincibility theme (itself a feel-good sound) but rocked up and really gets the impression of "powering up". Also, unlike the Sonic 3 version, it's not just a loop of a few seconds.
More or less every stage music deserves mention here:
The Special Stage Theme. This is the version heard ingame, where it gets fast and unbelievably awesome. That surreal blend of chirpy and mysterious at high speed is glorious.
Michael Jackson was the influence for almost the entire soundtrack of Sonic 3 (but very little to none of S&K). Ice Cap was influenced by "Who is it?" (or "Smooth Criminal"), and Carnival Night has riffs from "Jam" in it. Perhaps the most noticeable, the beats of the BGM in in the Marble Garden zones (Act 1) were heavily influenced by "Remember the Time".
The Boss theme, an upbeat theme that starts with a younger man and an older man laughing as if they're making fun of Robotnik for his continual defeats, getting your heart pumping as you "work that sucker to death!"
Palmtree Panic: the upbeat Present and Good Future. The former seems good for a day at the beach, while the latter is fitting for an outright beach party.
Wacky Workbench: the chaotic, fast-paced techno Present and the bright, mechanical Good Future.
Stardust Speedway: the funky Present, the darker Bad Future, and the much brighter, calmer, and peaceful-sounding Good Future. Note that the Bad Future music plays during the Metal Sonic race even in the Good Future.
Metallic Madness: The urgent Present, fitting for the final level, the you-screwed-up-big-time Bad Future complete with with sinister-sounding instead of jolly versions of the laughing men from the boss track and a robotic voice in the background saying stuff resembling anti-Sonic propaganda from Robitnik (e.g. "You can't do anything, so don't even try it," "Don't do what Sonic does," and finally, "Sonic, dead or alive, is mine"), and the a-winner-is-you Good Future that takes the instruments from the intro of the urgent present music and uses them for an upbeat background instrument.
"Calm After the Storm" , a relaxing, upbeat number that ostensibly serves as the music for the Egg Carrier after it crashes into the ocean, but for whatever reason, doesn't get used for this purpose. It's only used once in the game, during a cutscene of E-102 Gamma boarding the ditched carrier.
While not being all powerful, manly or exciting like most music here in this page, Chao Garden on Sonic Adventure 2 is the most relaxing (and cutest) piece of music around. It's awesome in its own way.
Hang Castle, or at least the default, non-inverted version of the theme.
Egg Fleet. And compared to most of the other tracks in the OST, which were happy and rocking, Final Fortress is no slouch either, with its definite intensity, cementing it as the final stage indeed.
Ocean Palace. sounds very energetic and cheerful while managing to sound very EPIC at the same time. It has one of the most well-composed, eargasmic climaxes ever composed with an electric guitar in any videogame.
Sonic's ending theme was originally the ending song for Sonicthe Hedgehog 2 for the Mega Drive; it was called "Sweet Sweet Sweet" and was performed by the Japanese band Dreams Come True. For Sonic06, they actually did a remix of this song for Sonic's ending, and they did it with Akon! The Japanese version is "SWEET SWEET SWEET -06 AKON MIX-" and the English version is "Sweet Dreams". Pretty smooth tune, even if the English lyrics can be disturbing when one thinks about Sonic's, uh, kiss.
Even more disturbing when you remember that this song originally appeared in Sonic 2, and was implied to refer to Sonic and Tails. (granted, Tails was originally intended to be a girl, so...)
Though it should be added that, while both versions can be listened to in-game (which one depends on your region; S'06 did not allow you to switch languages despite both being in the game), neither one was included on either the official soundtrack or the Vocal Traxx album, probably due to reasons.
How 'bout some event music? Mephiles' Whisper is supremely creepy, yet epic at the end as well. You Are My Companion (though not totally fitting for Silver's Ending) is a nice piece to set a tone of "I WILL get through the next character's story."
Crush 40's All Hail Shadow Remix from the game. It's one of their better covers of another band's song which actually manages to be better than even the original from Magna-fi. Just listen here which technically the Crush 40 remix first appeared in this game rather than Shadow the Hedgehog.
This song right here, which plays at the end of Shadow's story. It was actually part of the track "Showdown with Mephiles," for whatever reason.
From the DS version's exclusive Super Sonic final boss there is the Nega Mother Wisp's music which is another instrumental version of "Reach for the stars" only this time it plays like old school style game music but that doesn't stop it from being awesome.
Game Land 3, a remix of Starlight Carnival Act 1's music using the Game Gear's chiptune sounds. It definitely sounds like something straight out of that era, and it's beautiful. Not that the other Game Land songs aren't great as well.
To start with, the Hub World Music. ALL of it, especially the way the music transitions based on what stage/rival/boss you're near. For best results, try spindashing or boosting back and forth through the hub world at least once. It'll blow your mind
JP's Remix makes for a very funky party song, while US-version is more racing-induced and has very melancholy-sounding ambiance to it.
How about the DeathEggRobot boss fight, which has three stages of increasingly frantic awesomeness? First stage is all brass, the second phase adds more rock, and the final phase adds a psychotic drumbeat.
The Green Hills (yes, that's hills with an S) Zone tune from the Sega Master System version of Sonic 2. It's "Sonic ~ You Can Do Anything" from the Japan/Europe version of Sonic CD!!! Even better is that Sonic CD was made – or at least came out – way after the Master System version of Sonic 2, so for Sonic CD they took a tune from a (probably) lesser-known Sonic game and turned it into a song. THAT is awesome.
Actually, Sonic CD and both versions of Sonic 2 were all in development at the same time (Sonic CD was originally meant to be the SEGA CD version of Sonic 2), so it's not surprising that there'd be some links like that.
The Sunset Park Act 3 music from Sonic Triple Trouble, on top of being awesome, caught off guard many players who completed Act 2 and didn't expect the game to immediately segue into Act 3, with no end-of-stage bonus screen or title card in between.
That has largely to do (nowadays at least) with emulator issues that cause some of the synths in that tune to sound screwy. It sounds much better in the original Genesis cart (if you like that kind of music).
Despite being Dummied Out in the original game alongside its associated stage and character, the salsa-esque Sunset Town still makes appearances on the official soundtrack and with rereleases, and deservedly so.
The game's fast paced and energetic main theme gets you pumped up and ready to take on Robotnic as soon as you start playing! Also, the remix kicks ass.
Sonic Advance Invincibility. Sound familiar? Interestingly, they were going to use a different Invincible song, but they decided to go nostalgic, and instead it went to be used in Sonic Advance 2 and 3.
TechnoBase. It's an amazing song on its own, but it gets even more impressive when you realize that they made the GBA, a gaming system with a slightly more advanced soundchip than the SNES, produce full-on ACID TECHNO with a clear amen break sample in the second act! Truly an impressive feat.
Also the lost tracks: Broken by Sins Of A Divine Mother was to be used, but since they couldn't find one of the members to get permission, two of the others formed A2 and did Chosen One. Magna-Fi also had another song Who I Am.
Not to mention m-flo's remix of Tripod Baby to promote the game.
Then we have the insanely awesome Molten Mine music by Tommy Tallarico... which is itself a rearrangement of the "Action Theme" he composed for the completely-unrelated-to-Sonic game Black Dawn. Not that it's a bad thing.
Here's a Super Nintendo soundfont remix of Splash Hill!
Not only did their hit song "Sweet, Sweet, Sweet" get turned into the ending for Sonic 2 for the Genesis, Dreams Come True later took songs that Nakamura composed for the first two games, and turned them into hit songs!
For those wondering how the original trilogy's music would have sounded like on the good old NES, Danooct1's 8-bit VRC 6 remixes of Sonic 1to3 & Knuckles's OSTs are about as accurate-sounding as they'll ever be.
Masato Nakamura, the man who gave us the original Green Hill Zone and started a franchise trend for Music of Awesome. Sonic the Hedgehog would not be the same if it weren't for his original compositions for the start of this series.
While admittedly goofy (they did "I'm Too Sexy," after all), the music video for the Right Said Fred song "Wonderman" contains various references to Sonic the Hedgehog. The song itself was used in advertisements for Sonic The Hedgehog 3.
An honorary part of this page, Sonic Youth by Crush 40 sounds like it could have been the main theme of Generations. Its lyrics contain nods to much of the most famous Sonic songs, making it an awesome tribute to the soundtrack of the series. Some fans have even considered it an unofficial theme to Generations.
How awesome is Sonic music in general? Awesome enough to have one of the most popular internet radio stations on the entire web.
Before any piece of the Sonic Colors soundtrack was heard besides trailer music, props to whoever made this concept music which perfectly captures the tone of the game!
Not sure where else to put this but the Super Smash Bros. Brawl Remix of Sonic 3 & Knuckles' Angel Island Zone composed by Jun Senoue is pretty awesome.
Although not much is released, from what has been shown, Sonic After The Sequel's soundtrack is sounding even better. Two tracks have been revealed by MaxieDaMan and four tracks (plus a work-in-progress version of a fifth) have been released by Mr Lange.