Specifications

5.1-Channel Production Guidelines Production Environment
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real-time analyzer (RTA), rather than a Sound Pressure Level (SPL) meter. If an RTA
is not available, an SPL meter may be used to approximate the level. When the level
is correct , most meters will read around 90–91 dB SPL C-weighted slow for the LFE
channel. The difference in level is because there is no energy being reproduced for
the frequencies above 120 Hz (80 Hz for consumer applications).
A properly calibrated room will result in mixes that will sound correct when played
back in a consumer environment. An improperly tuned room will result in mixes that
will sound fine in the mixing facility, but will be incorrect in other situations. Using
the guidelines above will result in a properly tuned room. The room alignment has
little to do with the release format. A discrete six-track mix or a Dolby Digital
encoded DVD will reproduce equally well when these guidelines are followed.
3.4 Level Calibration
It is important to have a properly calibrated audio monitoring system to ensure accurate
encoding and decoding. Proper calibration requires the use of an SPL meter and an
RTA to measure relative and specific playback levels (in decibels) of all six channels.
3.4.1 Playback Levels
Use an SPL meter and a Pink Noise Generator to set your system’s playback level to
a particular reference level.