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Old 16th November 2009
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tragichero's Avatar

Originally Posted by minister View Post
It's happening because whatever device you are using to play it back has DRC (Dynamic Range Compression) on. You need to turn it off on the playback device. In the computer, it is in DVD Player in the preferences. It doesn't happen with aiff because there is no Dolby DRC engaged on playback.
you nailed it! When i disabled this, the program material returned to its original level and all the transients during that loudest section play back beautifully. I had no idea this was part of the Dolby spec.

This is exactly why I asked the OP what his mix levels were prior to encoding!
The majority of the material peaks between -18dbfs to -14dbfs. However, during the loudest section, i have peaks around -3dbfs. It seems i may need to add some 2bus compression to make the dynamic range smaller, in addition to bringing the entire level of the program material down so my peaks will be retained even if the DRC is engaged (and it very well could be as Geo's post points out).

A DVD player can play back in one of two modes: Line Mode or RF Mode. It sounds like yours is playing back in RF Mode. RF Mode applies 11 dB of gain and will limit any peaks above -11 dbFS even if you set the compression profile to None. The only way to work around this is keep your peak levels below -11 dBFS. Anything above will be limited in a pretty bad way (fast attack with a slow linear release). I agree with the idea to try a different DVD player but if you are using the RF cable output, then it will always be RF Mode so don't use the RF cable out. If you are using the RCA plug line outputs, it should be a Line Mode decode. Look in the DVD player menu options to see if it is incorrectly set. But since you never know what kind of system your DVD will play back on, I recommend you always limit peaks to -11 dbFS for a stereo mix. For a 5.1 mix you have to limit even lower so that a downmix doesn't go above -11... trick stuff! By the way, we are working on a product that helps you navigate all this while mixing/mastering.

Paul Neyrinck
Again, this is fantastic information! Thank you!

If I follow Paul's advice and make sure that i do not have any peaks above -11dbFS, will my mixes play back most reliably in the majority of systems?

When mixing/encoding Live concerts for DVD, is there a standard level i need to follow or a general rule of thumb for my RMS and Peak levels?

I really appreciate everyone's expertise and guidance, you are brilliant resources!