Amplitude

Amplitude is a 2003 rhythm game released by Harmonix and published by Sony Computer Entertainment for the PlayStation 2, as the successor to Frequency. More general information is available on Wikipedia. Internally, the game is sometimes referred to as "freq2".

Versions

Official PlayStation Magazine (OPM) Demo

A demo of Amplitude was included on an Official PlayStation Magazine Demo disc (when?). This version includes a reduced selection of songs, a slightly tighter and harder engine, and interestingly an ELF file (See #Debug Symbols).

The demo uses data scripts in plaintext .txt files, compared to the retail version's encoded proprietary .txt.bin format. These .txt files are closely related to plaintext .dta files and share a lot of, if not the exact same syntax. These files also conveniently include comments left by Harmonix developers working on the game, which were stripped out in the final release during the conversion to .txt.bin.

Debug Symbols

The aforementioned OPM demo of the game contains a file named "#freq2_r.elf.1.240" within its main.ark. This file has ELF headers and symbol names for functions. (TODO: is this ELF the same as the compiled demo, or is it a debug build?)