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Chapter 3 ES2 98
Create FM sounds with unusual spectra
If you’re unconcerned with the pitch of your sound, you can get the weirdest spectra out of odd
frequency ratios—oscillator intervals.
The FM Out of Tune setting oers a bell-like sound, reminiscent of a ring modulator. It was
achieved through a setting of 30 s 0 c, with the modulator set to a value of 0 s 0 c. Sounds like
this were commonly used in the electronic music of the eighties and have had a resurgence in
popularity in ambient and trance music styles.
You can further develop the sound by applying ltering, envelope modulations, and eects.
There is, however, one small problem—the sound is out of tune.
Do the following:
m Use oscillator 3 as a reference for the tuning of the FM sound by dragging the pointer in
the Triangle.
m You’ll notice that the sound is ve semitones too high (or seven semitones too low, conversely).
m Transpose both oscillators 1 and 2 ve semitones (500 ct) lower. Transposing them upward is not
practical, as you’d need to select 37 s 0 c for oscillator 1, which has a maximum value of 36 s 0 c.
m It’s important to maintain the frequency ratio (interval) between oscillators 1 and 2. This means
that oscillator 1 sounds at 25 s O c and oscillator 2 at −5 s 0 c.
Create ES2 PWM sounds
Pulse width modulation (PWM) is one of the most essential features of any analog synthesizer.
Set up a basic PWM sound
m Choose the PWM Start setting, and move the Wave control slowly back and forth between the
rectangular and the pulse wave symbols. Both are green. What you will hear is a manual pulse
width modulation.
m Choose the PWM Slow setting. Here, LFO 1 controls the pulse width modulation source, not your
manual movements. The result should be quite similar.
m Raise the LFO 1 rate from its preset value of 0.230 to 4.400. The result is a classic, fast PWM.
m In this and the next step, the PWM is set so that it sounds slower in the lower keyboard range
and faster in the upper range. This is desirable for many sounds, such as synthetic strings. First,
reduce the LFO 1 Rate to 3,800.
m Change the modulation intensity of the second router channel (target = LFO1 Rate,
Source = Kybd) to 0.46. This alters the scaling of the PWM, making it sound faster in the treble
range. You can also hear this type of eect in the PWM Scaled setting.
Tip: Avoid Drive and Distortion with PWM sounds.