bass management and Dolby certification

[synthoid]

hi,

<I seldom post over here. >

I have been making tentative enquiries into what is required of a studio to obtain certification from Dolby, and I've noticed that all their documents on the subject specifically prohibit bass management systems. From their requirements doc for commercials and trailers for example:

Bass management systems are not acceptable.

And it is the same for their higher levels of certification.

I'm surprised by this stipulation because all the subwoofer systems I'm aware of involve filters in the sub that divert low frequency stuff into the sub itself.

Does this requirement mean that a certified studio must provide a surround environment that uses 5 full-range channels (without passing those channels through a sub), with the LFE delivered directly to a sub, i.e., something resembling actual theatre playback? Or does bass management have a different meaning than I'm reading into it?

I'm guessing that bass management systems are often used for premix but not for mastering for surround formats. Is that right?

Sorry if these are ignorant questions, I'm new to surround mixing and monitoring.

-synthoid

[dmitri]

If your are asking about Dolby approval for studios, intended for Dolby sountrack printmastering for theatrical film releases, then yes, "certified studio must provide a surround environment that uses 5 full-range channels (without passing those channels through a sub), with the LFE delivered directly to a sub, i.e., something resembling actual theatre playback"
To say more, the sound reproduction system should not only resemble, but be similar to the theatre playback.

[synthoid]

thanks!

-synthoid