They appear to be made of a glass or clear/white crystal like material that resemble musical instruments and have the power to transform into its respective instrument when the wearer touches them in a blast of colored light. The power of these medallions can only be unlocked when the siblings achieve harmony with one another and later were able to use their medallions power freely.
When in instrument state, they can be used as traditional musical instruments, or can be used as powerful weapons in combat for self-defense. However the use of the instruments, for either combat or music, costs power and after use the instruments will return into its medallion state to "recharge".
An important use for these artifacts in medallion state is there ability to free the mind of those roboticized, this is done when the power of the medallions is directy forced to the Robian through a stream of energy that overcomes the mind control and frees the conscious. However this process uses a lot of medallion energy and the effects are only temporary as after awhile the mind will be roboticized again.
Sonic on guitar
Sonic plays an electric multi-neck guitar. The body of the guitar being purple and yellow resembling Sonic's head. The guitar is capable of shooting lasers from the headstock, the trigger of this laser sometimes being the strum of the strings. Unlike the other two medallions the guitar has the least amount of powers only.
As a medallion, it is carried with red string and gives off blue light when used.
Manic on drums
Manic plays the drums, unlike traditional drums they appear more of circular machines with yellow rims, with only the cymbals being traditional. Manic can create and control quakes with his drums which is effective for leveling and demolition. He is also able to push and force earth and rocks skywards. When under fire the cymbals can be used as reflective shields to defend himself with. Manic's medallion is said in series to extremely dangerous if not used with caution due to its seismic powers.
As a medallion, it is carried with blue string and gives off green light when used.
Sonia on piano
Sonia plays an electric keyboard which comes with a stand for Sonia to play, or as a weapon the keyboard can alternatively be a dual-handed laser gun. The laser point being at the side of the keyboard and has a gun trigger for laser fire. Played as an instrument, a second laser can be shot from the back of the instrument when certain keys are pressed. Other than lasers, Sonia is able to summon mist when she plays a certain tune, this granting her and her brothers cover for escape or confusion.
As a medallion, it is carried with yellow string and gives off pink light when used.
In the episode "Head Games", it shows that Speedster Island has statues dedicated to its protective deities. These statue greatly resembled the hedgehogs and Manic studies the statues and the "♫" symbols on their necks. He finds that the music and power from the medallions can bring the statues to life, eyes glowing with the medallions light. The hedgehogs controlled the statues to to fight off Robotnik's invading forces.
- The medallions' powers are similar to the power of a ring.