Dave Smith Instruments Prophet 08 PE, Руководство по эксплуатации

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Sequencer
For many musicians, the term sequencer has become synonymous with MIDI
sequencer; that is, a computer-based application or dedicated hardware device
for recording and playing back notes and performance gestures via MIDI. But
sequencers were around long before MIDI. The Prophet ’08’s sequencer is much
more like the original analog sequencers typically associated with modular
synthesizer systems. The sequencer comprises four 16-step sequences that play
in parallel. Each sequence can be routed to a chosen destination, and each step in
a sequence can be set to a different value used to modulate that destination.
1 2 3 4
1
2
3
4
5 6 7 8 9
Steps
v = step value
Dest. 1
Dest. 2
Dest. 3
Dest. 4
10 11 12 13 14 15 16
S
e
q
u
e
n
c
e
Strictly speaking, the Prophet ’08’s sequencer does not play notes, nor does it
transmit MIDI data. If none of the sequence destinations are routed to oscillator
frequency, the sequencer may not even affect the pitch. In Prophet ’08 terms, a
sequence is just a series of events at timed intervals that changes the value of
one of the synth’s parameters in discrete steps. Because the four sequences play
in parallel, up to four parameters can be affected by each step, one per sequence.
For the most part, the sequence destinations are the same as the modulation
destinations, which is appropriate: a sequence is just another modulation source.
For each sequence step, the envelopes are gated on for half the step’s duration.
The duration varies according to the BPM and Clock Divide settings (or the
MIDI clock, if synced to an external source). The envelope settings of the
current program ultimately determine how long each step plays, though, and
longer (more legato) or shorter (more staccato) effects can be achieved by
editing the envelope rates.
The Prophet ’08’s sequencer is a gated sequencer. That means it requires a note
to be gated on—that is played from the keyboard or via MIDI—in order for the
sequencer to run. There is no dedicated start or play button and it does not
respond to MIDI start/stop/continue messages, but it can still sync to an external
clock. Simply turn on the sequencer and then play and hold a note to start.
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