User guide

DSP presets
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The digital surround processor provides eight alternative music
DSP presets designed for the reproduction of well-recorded
material, originally intended for replay over a traditional stereo
pair of loudspeakers. In addition, it provides DSP presets for
reproducing music in the digitally encoded DTS and MPEG
formats:
Audio format Presets
Conventional stereo Direct, Music, Trifield, Ambisonics, Super
(PCM) Stereo, Stereo, Music Logic, PLII Music
DTS DTS Music
MPEG MPEG Music
Music
The Music DSP preset extracts the mono and surround
components of the original recording. These components
provide an alternative representation of the original sound, and
this representation is sometimes used for recording systems or
in broadcasts such as FM radio.
The mono element is equalised using a proprietary Meridian
technique to match the tone colour of the centre speaker, and to
compensate for the fact that the frequency response of human
hearing changes with direction.
The Music DSP preset is recommended for recordings made
with spaced omnidirectional microphones, or using a mono-
surround technique.
Trifield
As for the Music DSP preset, the Trifield preset extracts the
mono and surround components of the original recording. It then
calculates the signals for the front left, centre, and right
speakers, using the phase and amplitude differences between
the three front channels, to redistribute the sounds on a
frequency-dependent basis. This gives a significant
improvement over traditional stereo, which converts the
differences between the microphone signals into amplitude
differences in the speaker signals. This version of the Trifield
algorithm is virtually impossible to implement without digital
signal processing.
Trifield is recommended for well-made recordings and stereo
television broadcasts that are not Dolby Surround encoded. An
advantage over the Music DSP preset is that the front stereo
image is more focused, and the width of the image can be
adjusted.
Music DSP presets