T-44/48 Series Amplifier
Operation Manual
T-44/48 Series | rev.
firm. 1.258 and above
28
4.2.6 Gain and polarity
The gain page of the input channel selected allows users to increase or decrease the
amount of signal going into the selected input. Using “
SELECT
” encoder to highlight the Gain
value allows the value to be changed by the “
ADJUST
” encoder in
0.2dB
steps from
-40dB
to
+20dB
. The presence of an active Group Overlay parameter is indicated by the ‘[]’ symbol (See
Overlays). This page will also allow users to change the polarity of the selected input from
normal to reverse and to mute the selected channel.
4.2.7 Delay
The delay page which controls the amount of delay associated with the input channel
selected and is adjustable from 0 to 998ms. The delay parameter is adjustable in fine steps at
low values; the adjustment becomes progressively coarser as the value increases. The
presence of an active Group Overlay parameter is indicated by the ‘[]’ symbol.
See Overlays on
page 14.
4.2.8 High Pass Filter
System high pass filtering is provided for the input signal. Filter type is selectable from
1
st
order, Butterworth, Bessel, Linkwitz-Riley and Hardman. Filter slopes of up to 4th order or
24dB / octave are provided. Not all filter types are available in all slopes. For example 18dB /
octave Linkwitz-Riley filters do not exist.
The Hardman type filter is always described by its’ order as the filter becomes progressively
steeper rather than following a linear slope so a dB/octave description is not accurate.
4.2.9 Parametric Equalization
There are nine stages of equalisation available for each input channel, three shelving
filters and six parametric filters.
4.2.10 FIR Shelving EQ
The Input High Shelf EQ is implemented using a
Finite Impulse Response
(
FIR
) filter,
and exhibits a linear phase response; that is all frequencies are delayed by the same amount.
This can be important in applications where different amounts of EQ are applied to different
parts of a speaker cluster, such as to add 'Throw' EQ boost so that parts of cluster which are
throwing further can have HF absorption correction added. If this EQ is not linear phase, then
the zones where the speakers combine may suffer frequency response anomalies.
Being a linear phase FIR equaliser, this necessarily introduces some latency delay,
which is constant regardless of the settings. However, when the ‘Enable’ parameter is set to
“Off”, it is removed from the signal path entirely, so it does not add any latency. In this page you
can change the frequency parameter from 2kHz to 20kHz, enable/disable the filter, and change
the cut or boost in 0.2dB increments.
The presence of an active Group Overlay parameter is indicated by the ‘[]’ symbol being
appended to the Gain value (See Overlays). The filter (and its associated latency) can be
completely removed by setting the enable parameter to the “Off” position. Note that this EQ can
only be used in Module Groups if set to ‘On’.
Also see Latency Delay on page 25.
A
GAIN
Gain
Pol
Mute
Preset1
0.0dB
Norm
Norm
