One of the CPU accelerators for the Apple II series is the RocketChip, which came in 5MHz and 10MHz versions. It came with a floppy disk that contained a number of utilities for manipulating the behavior of the chip, including CPU speed, slot caching, acceleration of the monitor WAIT routine and so forth.
One of the features of the chip was to automatically slow down the CPU whenever the speaker was accessed at location
$C030. When the chip was running at full 5MHz speed, this would cause tight operations like the system beep to sound normal while the rest of the machine ran fast. This default behavior was settable by one of the included utilities called
AUDIO.NORMAL. If you wanted to disable this setting and instead have the system run full speed when clicking the speaker, another utility was included called
That being said, there were three other audio-related utilities included:
AUDIO.MUSIC. While the first one really speaks for itself (it simply ignores access to the speaker's
$C030 location), the other two have always been a bit of a mystery to their actual function. The manual - in all its 14 pages of glory - only briefly acknowledges the HIFI and MUSIC tools saying that those modes will slow down the Apple during game play. Helpful, for sure.
So my question is, has anyone ever figured out what exactly the HIFI and MUSIC settings actually did?