Additive Synthesys with ADD-2

The ADD-2 Class realizes an Additive Synthesis with the following controls:

• The main amplitude,
• The oscillator's frequency,
• The attack and the decay of the amplitude envelope (linear),
• The range of a random vibrato.

The frequency of the oscillator is f0*scal.

The maximum range of the random vibrato is f0*jtf

The example A focuses on the vibrato range. The jitter's list (0.01 0.025 0.05 0.1 0.25 0.5 1) increases the random vibrato from 4.4 (440*0.01) to 440 Hz (440*1).

The example B deals with the attack and the decay times of the amplitude envelope.

The example C demonstrates the meaning of the spectral scaler. The random vibrato is always 4.4 Hz while the frequency goes to 440 to 3520 (440*8) Hz. So the first frequency has a 1% random vibrato but the last one has a 0.125% random vibrato.

The example D shows how to get always the same random vibrato range. In this case is always 1% of the frequency.

instr 1

idur = p3

iamp = (p4 > 0.0 ? (p4*0.001*0dbfs) : (ampdbfs (p4)))

ifund = p5

ifq = ifund * p8

imindec = 0.01

irise = p6

idec = p7

idec = (((irise+idec)>idur) ? idur-irise : idec)

if idec > imindec goto goon

irise = idur/2

idec = idur/2

goon:

iran = p9

iampran = ifund * iran

afqr randi iampran, 10

aenv linen iamp, irise, idur, idec

asound poscil aenv, ifq + afqr, 1

out asound

endin