User guide

DSP presets
43
Music and Trifield DSP preset
parameters
Parameter Options What it changes
HS Out? * Y or N High-rate audio.
Centre Flat, EQ1 to 3 The timbre of the centre
loudspeaker.
Width † 0 to 1.5 The width of the image.
Surr. Rear Surr. Rear, Switches the surround signal
Surr. Side, between the side and rear
Surr. All speakers.
R Filter Off, 1kHz, 3kHz, The cutoff of high frequencies
7kHz from the rear surrounds.
S Filter Off, 1kHz, 3kHz, The cutoff of high frequencies
7kHz from the side surrounds.
* Y gives high-rate audio, upsampled if necessary. N gives
standard-rate audio, downsampled if necessary.
† Trifield only.
Ambisonics
The Ambisonics DSP preset is designed for replaying material
encoded in UHJ format, the two-channel stereo-compatible
encoding found on Ambisonically recorded discs and
broadcasts. This material is specifically encoded for surround
reproduction and can give breathtakingly realistic sound when
replayed using the digital surround processor.
Ambisonic surround sound is quite unlike conventional stereo. A
special microphone technique picks up the sound of the original
performance in all three dimensions, allowing an archive to be
made which describes the sound field exactly at that position.
The microphone signals are then encoded using a phase-
amplitude matrix to allow the effect to be conveyed on two-
channel carriers (like FM radio, LP, or CD).
The digital surround processor uses accurately matched,
frequency-dependent, phase-amplitude matrices to decode the
signal and construct the signals for each speaker feed.
The fundamental difference between Ambisonic surround sound
and conventional stereo is that the signals from all the speakers
combine to produce a coherent sound field at the listening
position, giving the illusion that you are sitting inside the