User Manual

Multichannel Monitoring Tutorial Booklet (M2TB) rev. 3.5.2
Masataka Nakahara : SONA Corporation
©2005 YAMAHA Corporation, ©2005 SONA Corporation
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[Regarding LFE recording and playback levels] Excerpted and summarized from the DVD-Audio
Software Production Guidebook (Supplemented Edition)
Systems such as Dolby Digital prescribe the mechanism by which the LFE level is boosted during
playback, and LFE is boosted (+10 dB) by the playback system in the same way during production as
well. On the other hand in DVD-Audio specification audio tracks (LPCM, MLP), the LFE signal level
(not the signal amplitude itself, but the playback reference level) is handled in the same way as other
channels, and it is assumed that all channels will be at the same level. This means that LFE does not
require any special handling in the way of level adjustments at the time of production. The final LFE
volume obtained in the end-user environment may be affected by numerous factors, such as the bass
management system applied by the user's system. Ultimately, if we are not taking bass management into
consideration, the signal level of all channels should be thought of as equal.
Thus for DVD-Audio and Super Audio CD, note that the LFE playback level must be +/-0 dB just as the
other channels, which is -10 dB in comparison to DVD-Video playback environments such as Dolby or
DTS. The frequency bandwidth of the LFE signal also differs from DVD-Video in that since an LPF is
not applied during encoding, full-range recording and playback is possible. However as stated in the
“DVD-Audio Software Production Guidebook (Supplemented Edition),” it is desirable that an LPF be
applied during production to the LFE master source in order to maintain compatibility for a variety of
end-user playback environments.
Attention must be paid to the playback level of the LFE signal particularly when producing DVD-Audio
and DVD-Video hybrid multichannel discs. For example, in order for an LFE signal produced in a DVD-
Audio environment to be converted for use with DVD-Video, the LFE master signal must be recorded at a
level 10 dB lower.
[Front channel]
Level
L = C = R
Playback bandwidth
Full-range
[Surround channel]
Level
3-1: S=(LS+RS)=L/C/R, LS= RS ≈ L/C/R - 3dB (DVD-Audio)
5.1: LS = RS = L/C/R
Playback bandwidth
3-1: Full-range (DVD-Audio)
5.1: Full-range
[LFE channel]
Level
Band level +/-0 dB (same as main channels).
Playback bandwidth
Not specified (full-range is possible)
[Monaural surround in DVD-Audio and Super Audio CD]
Monaural surround in DVD-Audio
DVD-Audio provides monaural surround (S=LS+RS) formats, of which 3-1 (L/C/R/S) is an example. In
this case, the LS and RS playback levels are (LS+RS)=L=C=R, and LS=RS ≈ L/C/R-3dB. Thus in DVD-
Audio, it is necessary to re-adjust the LS and RS playback level depending on whether you are producing
for 5.1 or 3-1. This is the same for DVD-Video. In other words in DVD-Audio, multi-channel production
can use the same playback environment DVD-Video with the exception of LFE.
Below, we summarize and excerpt from material on monaural surround in the “DVD-Audio Software
Production Guidebook (Supplemented Edition), DVD Audio Promotion Conference.”