ProTrekkr (formerly known as NoiseTrekker by Juan Antonio Arguelles Rius aka Arguru) is
a tracker program combining a software synthesizer together with a traditional samples
tracker which can be used to create electronic music (like psytrance, trance goa,
hard acid, IDM, chip, techno, etc.) for small sized intros, demos or games.

v1.97c:

- Even more constants (Especially for modules not using instruments).
- Constants weren't generated correctly when using command 0x15.
- Implemented vibrato effect (0x1dxy) x = speed y = depth
(can't be used if arpeggio (0x1b) is turned on).