One Channel Of 3 Band Enhancer - Kurzweil K2600 Musician’s Reference

960 3 Band Enhancer
3 band spectral modifier
PAUs: 2
The 3 Band Enhancer modiÞes the spectral content of the input signal by boosting existing spectral
content, or stimulating new ones. First, the input is non-destructively split into 3 frequency bands using 6
dB/oct hipass and lopass Þlters (Figure 1). The high and mid bands are separately processed to add
additional high frequency content by using two nonlinear transfer functions. The low band is processed by
a single nonlinear transfer to enhance low frequency energy. Each band can also be separately delayed to
sample accuracy and mixed back together in varying amounts. One sample of delay is approximately
equivalent to 20 microseconds, or 180 degrees of phase shift with the KDFX 24 khz sampling rate. Using
what we know about psychoacoustics, phase shifting, or delaying certain frequency bands relative to
others can have useful affects without adding any gain. In this algorithm, delaying the lower bands
relative to higher bands brings out the high frequency transient of the input signal giving it more
deÞnition. Conversely, delaying the higher bands relative to the lower bands brings out the low frequency
transient information which can provide punch.
L Input
Crossover
Figure 10-88

One channel of 3 Band Enhancer

The nonlinear transfers applied to the high and mid bands can be used to generate additional high and
mid frequency content when Xfer1 and Xfer2 are set to non-zero values. As the value is scrolled away from
0, harmonic content is added in increasing amounts. In addition, setting both positive or negative will
respectively impose a dynamically compressed or expanded quality. This type of compression can bring
out frequencies in a particular band even more. The expanding quality is useful when trying to restore
transient information. More complex dynamic control can be obtained by setting these independent of
each other. Setting one positive and the other negative can even reduce the noise ßoor in some
applications.
The low band has a nonlinear transfer that requires only one parameter. Its affect is controlled similarly.
Parameters
Page 1
In/Out
CrossOver1
CrossOver2
Drive
Hi
Mid
Lo
In or Out
17 to 25088 Hz
17 to 25088 Hz
Delay
XFer
Delay
XFer 1 XFer 2
Delay
XFer 1 XFer 2
Out Gain
KDFX Reference
KDFX Algorithm Specifications
Mix
Out Gain
Off, -79.0 to 24.0 dB
L Output
10-163