AC3 audio distortion and levels.

[hatetea58]

I've been using the Final Cut Studio for a handful of years now. I usually use aif audio when encoding to DVD just because I think it sounds less compressed.

I'm using Compressor and DVD Studio Pro 4 to build a DVD of a 90 minute feature with Directors commentary plus a helping of extra video tracks for the special features. Using a DVD-5 there's just not room to use a aif audio (especially when there are two 90 minute audio tracks for the feature) so I'm forced to use ac3.

I'm sure we're all aware that there's a volume level difference between ac3 and aif versions of the same file.

When I encode to ac3 I make sure I set the Dialog Normalization to -31 and the Compression is set to none.

To make up for the loss in volume level going to an ac3, I increase the volume level in FCP before I export, even if it makes some of my audio clip in FCP.

When playing back on a set top DVD player, 5 out of 6 players it sounds great. No distortion, no clipping, perfect. But on one player it sounds terrible. The kinda of terrible you feel when you've spent weeks building something and are 2 days past the deadline already and it's now having problems.

I'm wondering if there are any solutions. Is all I can do is lower the levels in FCP and live with the softer sound output of ac3?

Any ideas or suggestions would be awesome.

Thanks!

[Ghitulescu]

1. you can't use AIF for creating a DVD-Video. You may use it however if you create an A/V-file (AVI, QT, MKV) and burn it as data-DVD.

2. Simply set the problematic player to output the DD as bitstream and let the AVR do the conversion. If possible. The clipping is done by the insufficient analog headroom. To be fully DVD compliant, try to keep the level below -12dBfs (actually it's -18 but -12 is ok).

[hatetea58]

thanks for your idea