AUDxPER

        A sound's frequency is determined by the value
        stored here.  The lowest value you should use is
        124, since this is about as fast as the Amiga can
        go.  The highest value is 65535.  NOTE:  You MAY use
        lower values than 124 on multisync modes.


        How you determine the period depends on how you get
        your waveform data.  If you use a digitizer and the
        frequency is in Samples-per-second, use this
        equation:                   3579546
                    AUDxPER = --------------------
                               Samples-per-second


        If you have a group of data that you want played as
        an "instrument", use this:
                                 3579546
        AUDxPER =  -------------------------------------
                   Bytes-Length * Frequency to be played


        Of course, the frequency for a given note may be
        calculated by the old standby:
        Frequency = Base * 2 ^ (1/12)


        Which calculates the frequency for the next note
        once given a frequency.  Middle C comes in at 261.4 Hz.


        If you don't want your sound to repeat, you should
        consider one more thing:  when to stop the sound.
        You see, the faster you play the sound, the faster
        its going to finish.  To figure out how long to let
        it play, use the following equation:
           uSec = .279365 * Period * Length
        Where uSec, is of course, the time in microseconds
        it takes to play your sound once.