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SOUNDSHAPER: CDP REFERENCE

ARPEGGIATE - arpeggiated selection/emphasis of partials


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SPECTRAL > EMPHASIZE > ARPEGGIATE >

SUMMARY
Arpeggiate the spectrum. A waveform sweeps up and down through the spectrum at a specified rate (frequency), selecting or emphasizing the partials it passes through, or which lie below or above it.
 
The focus (selection/emphasis) is on a band of frequencies (by default the channel bandwidth) ― the Sweep Band, whose centre is sweeping up and down. The sweep is between lo freq and hi freq; these limits define the main Frequency Band:

In Modes 1-3*, only the selected partials are played; in Modes 5-6, these partials are amplified; Modes 7-8 initially play the selected components, then the whole sound as normal.


MODES
 1. On:      Play only partials within arpeggiated Frequency Band.                           
 2. Below: Play only partials within and below Frequency Band.
 3. Above: Play only partials within and above Frequency Band.
 4. Boost:  Emphasise partials within Frequency Band; others are unamplified.
 5. Boost below: Emphasise partials within and below Frequency Band after initial sweep (not wave type 1).
 6. Boost above: Emphasise partials within and above
Frequency Band after initial sweep (not wave type 4).
 7. Once below:  Play only partials within and below
Frequency Band once; then play whole sound as normal (not wave type 1).
 8. Once above: Play only partials within and above
Frequency Band once; then play whole sound as normal (not wave type 4).

PARAMETERS
 wave type The waveform used for the sweep.
Values: 1. DOWN-RAMP   2. SINE   3. SAW   4. UP-RAMP (See Mode for certain restrictions.)
 rate  Number of sweeps per second
Range: 0.001- 344.5 Hz  T-V (varies with PVOC Analysis Sample Rate e.g. 344.531 is for 1024 points)
 [start phase]  Initial phase of sweep waveform. May have limited effect on sound.    
Range: 0-1.  (Mode 8: must be > 0.5 with sine/saw wave types)
 [lo freq]  Lowest frequency that arpeggiation sweeps down to.
Range: 5-22050 Hz, default 0 Hz. T-V
 [hi freq]  Highest frequency that arpeggiation sweeps up to.
Range: 5-22050 Hz, default 22050 (Nyquist). T-V
 [bandwidth]  BANDWIDTH of Sweep Band, in Hz.  (Not Modes 5 and 6.)
Range: c. 43 - 22050 Hz. Min. and default = channel bandwidth (Nyquist/channel_count). T-V
 [amplify]  Amplification of arpeggiated partials; (0 to 10000, default 10.0)
Range: 0 to 10000, default 10.0. T-V
 [decay rate]  Non-linear rate of decay of arpeggiated tones (default linear); > 1 is faster, < 1 is slower.
Range: 0.02 to 50.0, default 1 (linear). Values higher than about 7 can reduce output to silence T-V
 [sustain]  Number of analysis windows over which arpeggiated partial sustained. High values, especially combined with a long decay time, can cause amplitude overflow.
Range (windows): 1 - number of windows; default 3. T-V

NOTES
Mode 1 picks out the component partials in turn: this can be useful for analysing the content of an inharmonic sound.
Mode 2 is akin to a filter-sweep effect: the partials are arpeggiated on top of the original sound.
There appears to be a delay before the effect kicks in.
N.B. * Soundshaper's mode numbering is slightly different from CDP's.


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