Film-Tech Forum ARCHIVE: Maximum levels

This is topic Maximum levels in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Amanda Mundin (Member # 3386) on 11-17-2005, 01:10 PM:

Am I right in thinking the maximum levels produced by a digital soundtrack should be 105db for LCR, 102 db for LS+RS and 115db (10db above screen channels) for LFE?
And cinemas should be able to produce these levels at 2/3rds of the way back from the screen to the back wall?

Posted by Gordon McLeod (Member # 33) on 11-17-2005, 05:27 PM:

basically yes as long as it was setup for 85dbc with the fader at 7 and then no one raises the fader

Posted by Samuel Hynds (Member # 2610) on 11-18-2005, 09:27 AM:

When making specifications for a room:

Screen channels - 103dB @ 2/3 of Screen to Last Row
Subwoofer channel - 113dB @ 2/3 of Screen to Last Row
Side Surrounds - 103dB @ 2/3 the Width of the Room
Back Surrounds - 103dB @ 1/2 the Length of the Room

With Back Surrounds - the power required for EACH channel is half of the total required for the Back Surrounds.

The room is then set-up:
Screen channels - 85dB @ 2/3 of Screen to Last Row
Side Surrounds - 82dB @ 1/2 the Width of the room
Back Surrounds - 82dB-85dB @ 1/2 the Length of the room
Subwoofer channel - +10dB of Center channel.

If you want the '105dB'; you will need double the power of the amplifier or add more drivers.

Hope this helps - Sam [Cool]

Posted by Amanda Mundin (Member # 3386) on 11-19-2005, 06:14 AM:

Thanks for the help