15.0

Synthesis models
The sound synthesis in BeatBox 2 consists of a simple sampler and a synthesizer which includes three
different synthesis modules.
Sampler
The sampler plays short sound recordings ("samples") in different pitches. The sampler is intended for
creating all kinds of drum sounds; the sounds are static and unnatural if the pitch is not altered. This is
why the sampler is combined with on of the three synthesis models.
Filtered noise
White noise is filtered by two band-pass filters with separately setup frequencies and resonance. This
algorithm is suitable for creating synthetic snares and high hat sounds.
Phase distortion synth
Two oscillators with regulated phase distortion and thoroughly variable frequency modulate each other
(FM/cross-modulation/ring-modulation). Depending on the setting, this algorithm can be used to create
kick, tom, or metallic percussion sounds; higher values for frequency and modulation level produce
noisier sounds for high hats or shaker sounds. Since the oscillator frequency can be set exactly according
to the musical pitch, this model can be used to produce mass lines or melodies.
Physical modeling
This is a simple physical model of an "abstract" percussion instrument. A fed-back network of delays is
caused to oscillate by an impulse of filtered white noise (exciter). Depending on the setting of the exciter,
the size of the model (surface), and the damping, a wide spectrum of natural sounding percussion
instruments like cymbals, claves, gongs, or triangles can be created.
Multimode filter/Envelope generator
Following the samplers and synthesizers, an inverse filter (multi-mode filter) is added to add the last bit
of polish to the drum sound. The envelope generator controls all time-dependent processes in the
synthesizer and sampler.
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