Sequential PROPHET-600 - BASIC OPERATION; 3-1 POWER ON; 3-2 PREPARATION

1-4 OSCILLATOR B
1. A ctivate TUNE. Switch PRESET off (Manual Mode) and patch according to Figure 1-
1 .
2. Switch on OSC B SAWTOOTH. This should enable a brassy sound.
3. Check MIXER operation by rotating through its range. Set fully CCW to OSC A.
Play some chords at the high end. There should be nothing audible. Leave MIXER set
fully CW, to OSC B.
4. Raise OSC B FREQUENCY gradually by each semitone (while playing six voices).
5. Check that the range is four octaves:
a. Set FREQUENCY to 0.
b. Play C5 (highest key). Remember pitch.
c. Turn FREQUENCY to 10.
d. Play Cl (second to lowest C). Must be same pitch.
6. Set FREQUENCY to approximately 4.
7. Check that FINE has a one-semitone range. Return to 0.
8. Switch SAWTOOTH off and TRIANGLE on. This should yield a pure timbre, with no
obvious distortion, but at a lesser volume than the sawtooth.
9. Switch TRIANGLE off and PULSE on. This should be a full tone with no apparent
distortion.
10. Adjust PULSE WIDTH and observe smooth change in timbre. Find the point where
the second harmonic (the octave) drops out. This square wave should be near "5" on the
dial for all voices. At the extreme knob settings the pulses will "thin out" until they
degenerate to dc, resulting in no audio output. Return to "5".
1-5 FILTER
1. Activate TUNE. Switch PRESET off (Manual Mode) and patch according to Figure 1-
1 .
2. Adjust CUTOFF to 5.
3. Increase RESONANCE. All six filters should start to oscillate between 7 and 8 on
the dial.
4. With RESONANCE at 10, all voices should have nearly equal volume and track the
keyboard in fairly good tune.
5. Adjust CUTOFF gradually. Listen for smooth frequency control of the resonating
filters. Return CUTOFF to 5.
6. Switch KEYBOARD to 1/2. Instead of tracking the keyboard semitones, the filter
will now track in quartertones.
1-8
TM600A 7/83