10
KCS Monitor Tutorial
Klippel R&D System
reducing the bass boost (using alignment filter of high order, increasing cut-off frequency)
reducing the
Excursion Limit
(see section above)
Note:
Limiter activation is indicated by a warning
‘KCS Output Limiter active’
popping up for a short
time in the
State
window.
1.7.3
Protection with separate ANC input channel
On certain special KCS configurations a dedicated input channel for active noise cancellation (ANC) is
available. In ANC applications the latency of the signal has to be minimized in order to reach the
desired cancellation effect.
The ANC signal is provided to KCS via a separate input channel to avoid unnecessary digital filters (EQ
/ Alignment) adding group delay to the signal. Also, a dedicated speaker protection system for ANC is
used with ultra-short latency (0.1 ms) while the audio protection system has a larger, configurable
latency to minimize audible artifacts.
Equalizer
(e.g. A6)
Audio Signal
KCS Audio Path with ANC
System
Alignment
Linearization
ANC Signal
Low-pass
1.5kHz
+
Audio
Protection
ANC
Protection
Output
Limiter
Note:
The fixed low-pass filter in the ANC Signal is only available upon special request and is
preferably applied externally prior to any KCS processing. The currently implemented 4
th
order
Butterworth filter at 1.5kHz adds 0.3 ms group delay to the ANC processing.
KLIPPEL
-1,5
-1,0
-0,5
0,0
0,5
1,0
1,5
74850
74900
74950
75000
75050
75100
75150
75200
75250
75300
75350
Voice Coil Displacement
xoffset currently not updated
X
[
m
m
]
Time [s]
xpeak
xbottom
xDC
xoffset
xprot
-xprot
xpeak anc
xbottom anc
