Before they were cranking out unwavering weekly DLC and allowing single-minded fathers to finally form that family band they've always dreamed of (despite having thoroughly untalented children), Harmonix produced a little-known gem titled Frequency, and shortly thereafter, a sequel named Amplitude. While attention on these titles was washed away by the rising of the Guitar Hero and Rock Band tides, we might be seeing more of them yet.
In a recent interview with Ars Technica, Harmonix CEO Alex Rigopulos declared his love for Amplitude, and mentioned his wishes to eventually revive the series. Considering that Sony owns that particular property, it would likely come in the form of a PSN download -- however, given their tireless Rock Band DLC schedule and their rapid, company-wide expansion, it might be a while before they can divert the necessary amount of focus to put Amplitude back on the multi-colored, instrument-specific tracks.