Empress Effects Tremolo2 - Manual (Page 13)

Recalling a preset via MIDI (Program Change Messages)
You can activate a preset by sending a MIDI Program Change
message. For example, sending a Program Change message of 7
activates preset 7.
MIDI Clock (aka MIDI Beat Clock)
The Empress Tremolo
2
will respond to MIDI Clock messages. MIDI
Clock specifies quarter notes, subdivided into 24 MIDI Messages.
Each quarter note corresponds to 1 period of the tremolo’s
waveform.
Warning: The Tremolo
2
listens for MIDI Clock messages by default.
If it receives a MIDI Clock message, it will rely on the messages for
its tempo. This means that the Tremolo
2
's volume will freeze if the
MIDI Clock messages are discontinued. To unfreeze the Tremolo
2
,
send a MIDI Clock Listener message (CC #51) with a value of 0.