Moog Music Little Phatty Stage II - Manual (Page 57)

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LP Stage II User’s Manual - Appendices
Page 59
LP Stage II User’s Manual - Appendices
Appendix B - LFO Sync Modes
There are two LFO Sync Modes: INTERNAL and MIDI CLOCK.
INTERNAL:
When the LFO Sync Mode is set to ‘INTERNAL’, the LFO rate is controlled directly via the MODULATION
knob (when the LFO RATE panel button is selected), or by Tap Tempo, or by sending a MIDI CC#3 com-
mand with a value between 0-127 (MIDI CC#3 controls the LFO RATE).
When the Tap Tempo function is engaged, the internal LFO Rate is adjusted directly by tapping the LFO
RATE button. You can also adjust the LFO rate using the MODULATION control as normal, and this will
override the rate set by Tap Tempo. Note that the LFO RATE panel button will continue to blink, indicating
that Tap Tempo is still active - you can tap in a new tempo at any time. To disengage Tap Tempo mode, press
and hold the LFO RATE button. The LFO Rate will remain at the last rate you selected.
MIDI CLOCK:
When the LFO Sync Mode is set to ‘MIDI CLOCK,’ the LFO rate is synchronized to incoming MIDI Clock
pulses, with one LFO cycle equal to the note duration set by the LFO SYNC CLOCK parameter. The Little
Phatty must have a MIDI Input enabled in the MIDI Setup menu in order to receive MIDI Clock. The Little
Phatty Stage II has both USB and standard DIN MIDI inputs, and can receive MIDI Clock signals on either
input. It is recommended not to send different clock signals to both inputs simultaneously, unless you want
some very strange LFO signals to result!
If you change the Sync Mode from ‘INTERNAL’ to “MIDI CLOCK” while the LP is not receiving a MIDI
clock signal, the actual LFO rate will not change right away; it will continue at the same rate. However, the
LFO rate is no longer being controlled by the internal LFO clock. This means that if you try to control the
LFO Rate from the panel knob or send a MIDI CC# 3 message while the LFO Sync Mode is set to MIDI
CLOCK, the actual rate of the LFO will not change. NOTE: These actions still update the internal “LFO
Clock rate” parameter, but this parameter is offline while the LFO Sync MODE is set to ‘MIDI CLOCK’. If
you change the LFO Sync Mode back to ‘INTERNAL’, the rate of the LFO will jump to the internal LFO
Clock rate.
If the LFO is synchronized to a MIDI Clock pulse and the MIDI Clock is stopped, the LFO will continue at
the last MIDI Clock rate it received. If you hear a change in the rate of the LFO when you stop sending a
MIDI Clock signal, it is a sign of jitter or instability in your MIDI Clock source. The Little Phatty performs a
running average of the clock pulses it receives, so the more stable your MIDI Clock source, the smoother
the resulting LFO waveform will be. Very unstable clock sources can cause distortion in the LFO waveform,
due to the constant LFO Rate corrections required to stay in sync with an unstable timing signal.
When the Tap Tempo is engaged and a valid tempo is tapped in, Tap Tempo overrides MIDI Clock sync for
the LFO. The LFO reverts to the MIDI Clock rate when Tap Tempo is disengaged.