A query to ask the selected Excitation object for its loudness.
the loudness in sone units.
The loudness is defined as
|∫df 2(e(f) - 40 phon) / 10|
where f is the frequency in Bark, and e(f) the excitation in phon. For our discrete Excitation object, the loudness is computed as
|Δf ∑ 2(ei - 40) / 10|
where Δf is the distance between the excitation channels (in Bark).
© ppgb, October 16, 1999