The IRQ Speeds RWC (Default Key fI whilst in the List Editor) defines the base frequencies of SFX and Song Tempos and is provided with two parameters.
The Tempo of any song is dependant on the Song Tempo set at the start of a song and may also be modified during the song in the Patterns. The Tempo is a counter reference. The counter counts down to zero at a rate specified by the Music Frequency. In Sonix this frequency was 100Hz, most other trackers are based on 50Hz.
AYT's IRQ speed may be altered using this RWC and the two parameters provided.
The SFX IRQ changes the IRQ frequency that the SFX is based on. By default this is set to 25Hz. This may be changed to 50Hz(Common in other platform trackers), 100Hz(Sonix frequency) or 200Hz(Creating very crisp transitions but at the cost of the most CPU time).
The Music IRQ is generally changed in order to gain a greater accuracy of the Music Tempo. Little CPU is lost at any speed but it is recommended to reduce speed if possible because the eventual music module will always run at the fastest IRQ speed. The Music IRQ speeds are 25Hz(Default speed but lowest accuracy in Tempo specified), 50Hz(Popular in other trackers), 100Hz(Sonix Music Frequency) or 200Hz(Fastest).