D.A.S. DSP-4080, Руководство пользователя

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<- Bandpass filter
InA Input A BPS:1/\
1k00Hz Q = 3.0 Bandpass
Remember – to change filter types, press BYPASS
to bypass the filter, and then use ENTER to select the
filter type.
The bandpass filter has adjustable frequency and
'Q' (or Bandwidth) controls. These affect a range of
frequencies symmetrically about the centre frequency
as shown in the graph, gradually cutting the level, but
providing no gain.
Remember that 'Q' is 1/Bandwidth, so the higher
the 'Q', the lower the Bandwidth, and the smaller the
range of frequencies affected.
Note that the response is fundamentally NOT a
flat-topped response (so it is not constructed from a
high pass and low pass). See previous page for details
of how to construct a flat-topped filter response.
<- Notch filter
InA Input A NOT:1\/
1k00Hz Q = 0.75 Notch
Remember – to change filter types, press BYPASS
to bypass the filter, and then use ENTER to select the
filter type.
The notch filter has adjustable frequency and 'Q'
(or Bandwidth) controls. These affect a range of
frequencies symmetrically about the centre freqency
as shown in the graph.
Remember that 'Q' is 1/Bandwidth, so the higher
the 'Q', the lower the Bandwidth, and the smaller the
range of frequencies affected. The notch filter depth
varies with bandwidth – the wider the filter, the lower
the depth will be.
<- All pass filter
InA Input A APF:10
1k00Hz Q = 3.0 Allpass
Remember – to change filter types, press BYPASS
to bypass the filter, and then use ENTER to select the
filter type.
The allpass filter has adjustable frequency and 'Q'
(or Bandwidth) controls. These affect the frequency at
which the phase effectively flips 180º, and the 'speed'
at which this transition occurs.
The graph shows an allpass filter centred at 1kHz,
with various 'Q' settings – the higher the 'Q' the faster
the transition.
DSP-4080
User’s Manual