Next  |  Prev  |  Up  |  Top  |  REALSIMPLE Top

Tonal Correction Filter

Let $ h_k(n)$ = impulse response of $ k$ th system pole. Then

$\displaystyle {\cal E}_k = \sum_{n=0}^\infty \left\vert h_k(n)\right\vert^2 = \hbox{total energy}
$

Thus, total energy is proportional to decay time.

To compensate, Jot proposes a tonal correction filter $ E(z)$ for the late reverb (not the direct signal).

First-order case:

$\displaystyle E(z) = \frac{ 1 - bz^{-1}}{1-b}
$

where

$\displaystyle b = \frac{1-\alpha}{1+\alpha}
$

and

$\displaystyle \alpha \mathrel{\stackrel{\Delta}{=}}\frac{t_{60}(\pi/T)}{t_{60}(0)}
$

as before.


Next  |  Prev  |  Up  |  Top  |  REALSIMPLE Top

Download Reverb.pdf
Download Reverb_2up.pdf
Download Reverb_4up.pdf

``Artificial Reverberation and Spatialization'', by Julius O. Smith III and Nelson Lee,
REALSIMPLE Project — work supported by the Wallenberg Global Learning Network .
Released 2007-09-19 under the Creative Commons License (Attribution 2.5), by Julius O. Smith III and Nelson Lee
Center for Computer Research in Music and Acoustics (CCRMA),   Stanford University
CCRMA