ALESIS M20 REFERENCE MANUAL 1.06 10-1

CHAPTER 10

VARISPEED
Varispeed changes the sampling rate to change the audio’s pitch. This feature only applies
when the Clock Source is set to INT (Internal). Pitch mode is automatically set to Fixed
whenever the M20 is being controlled by an external unit (for example, when SMPTE Chase
is on).
The varispeed range is -300 through +100 cents (-15.91% to +5.95%) at a base 48 kHz sample
rate and -200 through +200 cents (-10.91% to +12.25%) at a base 44.1 kHz sample rate. This
allows a total sample rate range from approximately 39.289 kHz (-200 cents @ 44.1 kHz) to
50.854 kHz (+100 @ 48 kHz). Note that pitch changes affect all slave machines. Varispeed
settings are retained in memory.
Operation You press… You see…
Enter Varispeed Edit
mode Varispeed button Display shows amount of
varispeed change in cents
and as a percentage
Set varispeed amount Enter amount with
numeric keypad or
Up/Down buttons.
When Vari is set to 000,
Up/Down buttons select
+ or - before entering a
number. If Vari is any
other value, Up/Down
increments/decrements
the value.
Display shows amount of
varispeed change
Enable varispeed Press Pitch Mode button
until… Vari in the pitch block
Disable varispeed Press Pitch Mode button
until… Fixed in the pitch block
In Varispeed mode, the time counters will not show the true elapsed (i.e., “clock on the
wall”) time intervals.
Synchronization warning: Any time code being sent from the M20 will be sped
up or slowed down when using Varispeed mode. This may cause synchronization
problems in other equipment that is slaved to the M20. If you’re using SMPTE time
code synchronization anywhere in your project, use varispeed with great caution.