You must beat special stage time attacks in under 4 minutes to unlock the Sound Test.
| Unlockable | How to unlock
|
|---|
| Hidden artwork 1 | PGM 12, DA 11.
|
| Hidden artwork 2 | PGM 12, DA 2.
|
| Hidden artwork 3 | PGM 03, DA 0.
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| Hidden artwork 4 | PGM 04, DA 2.
|
| Hidden artwork 5 | PGM 11, DA 0.
|
| Secret special stage | PGM 07, DA 07.
|
