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NEDSP1062-KBD Operating Manual
The
NEDSP1062-KBD
requires a signal of 125mV rms
or greater for optimum performance. Signals lower than
this may be used but the noise cancellation performance
will decrease, as the signal levels drops. If the unit is
used with low level signals such as microphones, the
signal will need amplifying before applying it to the
NEDSP1062-KBD
.
Due to the adaptive nature of the noise cancellation a
small delay may be heard when the audio signal
changes. For optimum performance provide the module
with a constant signal where possible.
When switching on the unit a thump may be heard in the
loudspeaker.
3.
Installation.
Figure 14. Input circuit -
module powered down
22
W
OUT
12
Agnd
Agnd
9
10
V
Audio
Input
NEDSP1062
R6
IN
Load
11
The audio input to the
module is loaded at
22
W.
This load is
effectively connected
across the output load
when the unit is
switched off
(bypassed).
This will reduce the
impedance presented
to the audio source.
For example:
8
W
will reduce to 5.9
W
4
W
will reduce to 3.4
W
3.2.3 Change to output load.
3.2.4 Other signal considerations.
