Sound Devices 744T - Manual (Page 30)

744T User Guide and Technical Information
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v. 2.67 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
If you press (done) in the first headphone slot, the 744T will select a single option (Tracks A, B) for head-
phone monitoring. The 10 factory presets will be erased.
MS Stereo Monitoring
The MS stereo mode decodes discrete Mid-Side stereo signals to a left/right stereo signal for moni-
toring purposes. This allows for a proper stereo signal to be monitored in the field while discrete M
and S signals are recorded for later post production. For the MS decoder to operate properly, the Mid
signal is connected to either input 1 (or input 3) and the Side signal is connected to input 2 (or input
4). The amount of stereo “spread” is fixed to a 50/50 percentage from Mid to Side signal.
If MS is selected for input linking, do not use MS stereo monitoring. This would result in two MS decod-
ers being inserted in the signal path. The resulting audio in the headphones would be the discrete M and
S signals!
SoundField B-Format Surround Monitoring
SoundField B-format is a four channel surround sound format generated by SoundField surround
microphones. The 744T can accept the four signals output from a SoundField microphone and record
each to its own track.
When recording four-channel B-format audio, the 744T headphone monitor can decode the B-format
signal into L/R stereo. The 744T constructs a stereo signal using the W, X, and Y signals of the B-
format. The Z-axis signal is not used. Similar to the 744T’s MS stereo monitoring, the stereo width is
fixed for headphone monitoring.
To record and monitor B-format signals, connect signals as follows:
SoundField Þ 744T Þ Resulting File Name (for monophonic file type)
W signal Þ input 1, track A Þ FILE _ 1.WAV
X signal Þ input 2, track B Þ FILE _ 2.WAV
Y signal Þ input 3, track C Þ FILE _ 3.WAV
Z signal Þ input 4, track D Þ FILE _ 4.WAV
SoundField files generated in other recorders or software applications can be copied to Compact-
Flash or the 744T hard drive and can be played back and monitored in stereo. Make certain that
channel assignments follow the order above for proper headphone decoding. If multiple monophon-
ic SoundField .wav files are named using the “_W, _X, _Y, _Z” suffixes, the 744T will recognize that
these are multiple monophonic B-format files and will play them back in the proper track order.
The 744T can play back monophonic or polyphonic B-format files.
There are two B-format monitoring selections, one for inputs and one for tracks. They are listed as
INPUT B-FMT STEREO and TRACK B-FMT STEREO. For most recording and playback applications
the track monitor selection is appropriate. If the user wants to hear the inputs at all times, the input
monitor selection is appropriate.