3
Trident Audio Developments
| Hi-Lo Dynamic Filtering User Manual
4
Trident Audio Developments
| Hi-Lo Dynamic Filtering User Manual
Lo-Cut Dynamic Tracking
continued
In practice, this technique de-
mands a trade-off between
noise reduction and loss of
some low frequency content of
the program material. However,
using the steepest (24dB per
octave) slope, maximises the
amount of low frequency content
retained. In addition, discreet
use of the RESONANCE control
to introduce a small peak of a
few dB at the cut-off frequency,
can psycho acoustically enhance
the apparent bandwidth of the
filtered signal. Use of higher
resonant settings will result in
the movement of the filter be-
coming audible and indeed,
combined with higher settings
of the FREQUENCY control, this
can be the basis of some unique
effects.
Further possibilities —
The sweep range of the Lo-Cut filter is extremely
wide, from effectively ultrasonic to right down to full audio bandwidth.
This sug-gests the possibility of fading tracks in and out, not in the ampli-
tude domain as usual, but in the frequency domain.
Again, connecting two Trident Hi-Lo modules in series, via an external
linking system such as on the Trident Deca Dent, permits filter slopes of
up to 48dB per octave to be realised(!).
Dynamic Linking Linked Stereo Tracking
Two Trident Hi-Lo modules can be employed for linked stereo tracking,
when used via an external stereo linking system, such as on the Trident
Deca Dent.
This is achieved by enabling both Hi-Lo modules TRACK SIGNAL switches
and setting the FREQUENCY controls to identical positions. The track signal
is generated by the sum of the left and right signals, and the automatic tracking
follows both the left and right signal sources.
—
S P E C I F I C A T I O N S
—
Input Impedance
10 kilohms
Max
Input
+27dBu
Max Output
+27dbu (Into 600ohms)
Distortion (+10dBu Out)
0.0031% (20Hz to 20kHz)
(Hi Enabled Max Freq)
(Lo Enabled Min Freq)
Distortion (+20dBu Out)
0.0069% (20Hz to 20kHz)
Frequency Response
15Hz to 60kHz (-3dB)
Noise
(20Hz to 20kHz bandwidth limited)
No Filters in circuit (Residual Noise)
-95dBu
High Cut Enabled
Freq
Max
-83.5dBu
Freq Min -90dBu
Freq Max – 24dB/Oct Slope Enabled
-80dBu
Freq Min – 24dB/Oct Slope Enabled
-90dBu
Freq Max – Res Enabled, Resonance Min
-83.5dBu
Freq Max – Res Enabled, Resonance Max
-72dBu
Freq Max – 24dB, Res Enabled, Res Max
-71dBu
Freq Min – Res Enabled, Resonance Min
-90dBu
Freq Min – Res Enabled, Resonance Max
-90dBu
Freq Min – 24dB, Res Enabled, Res Max -
90dBu
Low Cut Enabled
Freq Max -83dBu
Freq Min -86dBu
Freq Max – 24dB/Oct Slope Enabled
-83dBu
Freq Min – 24dB/Oct Slope Enabled
-90dBu
Freq Max – Res Enabled, Resonance Min
-84dBu
Freq Max – Res Enabled, Resonance Max
-72dBu
Freq Max – 24dB, Res Enabled, Res Max
-73dBu