GENsone

GCreates an ftable with values of the sone function for equal power.

Syntax

f # time size "sone" start end equalpoint rescale

Initialization

size -- number of points in the table. Must be a power of 2 or power-of-2 plus 1 (see f statement).

start, end -- first and last value to be stored. The points stored are uniformly spaced between these to the table size.

equalpoint -- the point on the curve when the input and output values are equal.

rescale -- if not zero the table is not rescaled

The table is filled with the function x*POWER(x/eqlp, FL(33.0)/FL(78.0)) for x between the start and end points. This is the Sone loudness curve.

Examples

Here is an example of the GENsone routine. It uses the files gensone.csd.

<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
-odac  ;;;realtime audio out
;-iadc    ;;;uncomment -iadc if realtime audio input is needed too
; For Non-realtime ouput leave only the line below:
; -o gensone.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

sr = 44100
ksmps = 32
nchnls = 2
0dbfs  = 1

instr 1 ; simple oscillator with loudness correction. 

kcps = cpspch(p4) 
kenv linseg 0, p3*0.25, 1, p3*0.75, 0   ;amplitude envelope
kamp tablei 16384 *kenv, 2 
asig oscil kamp, kcps, 1
     outs asig, asig

endin 

instr 2 ;neutral oscillator to compare with

kcps = cpspch(p4)  
kenv linseg 0, p3*0.25, 1, p3*0.75, 0   ;amplitude envelope
asig oscil kenv, kcps, 1
     outs asig, asig

endin 

</CsInstruments> 
<CsScore> 
f 1 0 16384 10 1        ;sine wave
f 2 0 16385 "sone" 0 32000 32000 0 

s
f 0 1   ;1 second of silence before we start...
s 
i 1 0 2 7.00 
i 1 + . 7.01 
i 1 + . 8.02 
i 1 + . 8.03 
s 
i 2 0 2 7.00 
i 2 + . 7.01 
i 2 + . 8.02 
i 2 + . 8.03 
e 
</CsScore> 
</CsoundSynthesizer>

This is the diagram of the waveforms of the GENsone routine, as used in the example:

f 2 0 16385 "sone" 0 32000 32000 0

See Also

More information on Sone: http://en.wikipedia.org/wiki/Sone

Credits

Written by John ffitch