Amplitude (PS2)

Black panel surfaces
Press R3, L3, R3(2), L3, R3, L3(2), R3 during game play. A sound will confirm correct code entry. Start a new game to have black panels.

Blur Mode
While playing a game, press R3(4), L3(4), R3.

Fast freestyle
If and when the freestyle line is straight and not meshy, hold Square and hold Right Analog-stick Right. If the freestyle line is blotchy and sprinkly, this will not work.

Invisible Track
While playing a game, press L3, R3, L3, L3, R3, L3, R3, R3, L3. Then pause and choose exit. Then re-enter a level and the track will be invisible.

Invisible Track
While playing a game, press L3, R3, L3, L3, R3, L3, R3, R3, L3. Then pause and choose exit. Then re-enter a level and the track will be invisible.

Maximum combos
When in freestyle mode, have someone else hold Square, Triangle, or Circle while you jiggle the Left Analog-stick as fast as possible.

Monkey Gems
Input this code while a song is playing:

These are to be pressed on the analog: Down Right Diagonal (x9)

Monkey Head Gems
While playing a game, press L3(4), R3(4), L3 to get monkey head gems.

Scramble Gem Positions
During gameplay, press X, X, LEFT, LEFT, R3, R3, RIGHT, RIGHT to switch up the gem positions.

Tunnel/Tempest Mode
While playing a game, press L3(3), R3(3), L3, R3, L3 to get a Tunnel style view. Enter the code again to get a Tempest style view.

Unlock Freq Parts
Beat the boss song of any level to unlock extra Freq parts.