Well, this is something that the 90s had.
For those who do not know, Sonic Underground was the third and final Sonic cartoon DIC entertainment made in the 90s. The plot to the show is shown in the intro. Sonic along with two siblings by the names of Sonia and Manic are the new-born children of Mobius' ruler, Queen Aleena, but when the devious Robotnik stages a hostile takeover of Mobius as foretold in a prophecy from the wise Oracle of Delphius, Aleena separates the little hedgehogs and goes into hiding. Our heroes soon grow up and the oracle sees them and tells them about the prophecy where in order to defeat Robotnik, they must find their mother in order to become The Council Of Four and stop Robotnik for good. He then grants them instrument shaped medallions that could turn into real instruments (guitar, keyboard and drumkit), not only for their own underground band, but also as a way they can defend themselves against Robotnik's army of SWATbots led by his notorious bounty hunters, Sleet and his shapeshifting cohort Dingo.

Now we come to the main three heroes and what they're like.
First Sonic-He's pretty much the same as he usually is in the 90's cartoons. Cocky chillidog lover and having a great fear of water.
Sonia- Considering how she was raised by an upper class family after being separated from her brothers, Sonia is not a fan of getting dirty and sometimes squabbles with her brothers, but that doesn't stop her from caring for them. She serves as the smartest of the trio, having a photographic memory. She can certainly put Robotnik's forces in a spin.
Then, there's Manic- Being raised on the street by a gang of thieves, Manic is a master of their trade (something his siblings don't take too kindly to) Considering he doesn't have a super speed, or super spin ability like his siblings to, Manic doesn't seem too bothered, all he needs is his drum medallion, his sneaky skills at stealing things and he's good to go.

The villains in the show of course include Robotnik where he is determined to have Aleena's kids captured and roboticized and won't be happy until this has happened and he has his SWAtbots and bounty hunters to fulfil his wish. Speaking of which.
Sleet is considered the brains of Robotnik's bounty hunters and is always eager to put Dingo's shapeshifting abilities to use, but is always getting more hurt than him when they fail to capture our heroes.
His partner, Dingo is ignorant, dim and has a crush on Sonia and he has a few roboticized parts here and there on him, namely his hands and foot. Why? It's never explained. He is all the same, loyal to Sleet, but he hates getting shape shifted.

Other characters that appeared in the show included, Queen Aleena, where she spends her time on the run from her children, keeping her face concealed until the time is right; she also narrates the start of each episode. The Oracle of Delphius, a reptilian anteater with vast knowledge and wisdom that foretold the prophecy to Aleena and her kids, I thought he was supposed to be a crocodile when I was a kid. Sir Bartleby Monteclair, an aristocrat that unwillingly supports Robotnik's funds. Cyrus, a young lion and technical expert who is old friends with Sonic. Doo Bot, a robot hairdresser that uses hypnosis to have conversations with her customers, even Knuckles appeared in the show, where he was portrayed as the gullible Master Emerald's guardian and acquaintance of Aleena. He even had a soft sign of affection for Sonia.

The show was pretty firm and more was probably planned, but I believe there was confirmation to the show being cancelled because of its low popularity. I assume this was due to the fact DIC Entertainment was toying with a whole new idea entirely with Sonic that the fans didn't accept.
I remember seeing reruns of the show in 2006, I thought it was an all right show and even found it a tremendous surprise when I found out that Jaleel White AKA Steve Urkel, the guy that voiced Sonic even voices Sonia and Manic in this show. I mean all three main protagonists voiced by the same guy; can you imagine seeing Urkel in his recording booth doing all the voices and lines of his characters during a conversation between themselves?
I find it a shame fans didn't give this much attention, especially with the songs heard in the show, performed by Sam Vincent, Stevie Vallance and Tyley Ross.
It's an even bigger shame for DIC Entertainment considering how they made this after making Sonic SATAM and how well received it was from fans.
Well, I hope you've taken good acceptance of my review. It may not be great, but I try.
Sonic belongs to Sega
Sonia and Manic belong to DIC Entertainment