audio editing

busterkeaton wrote on 5/21/2007, 6:17 PM

I got a clip from a coworker, the file was recorded too loud, the peaks looked like they are clipped, but not at 0db. The clips are occurring at -6db.

What's my best option for fixing this?
Boost the audio by +6db and then use sound forge's clipped peak restroation?

Comments

Bob Greaves wrote on 5/21/2007, 7:57 PM

That or a pencil tool. But this is a minimal recovery.

Widetrack wrote on 5/22/2007, 2:56 PM

When you see the peaks clipped, this means some problem in the recording/editing process has literally removed some of the information that comprises the audio signal at higher levels (volumes).

This information cannot be recovered.

But It also creates a nasty distortion when played back. I used the Sound Forge restoration tool once, and it reshaped the flat tops of the clipped waveform into nice smooth ones, removing most of the distortion. Doing it with the pencil tool would also work, but take a LONG time.

good luck.

WT

kronos78 wrote on 5/23/2007, 12:54 PM

Is the audio actually distorting? To me it sounds like the audio was processed through a limiter outputting at -6 dB. This will make it seem louder and looked like it was clipped. If if's just a matter of volume, you only need to turn it down.

reidc wrote on 5/26/2007, 11:36 PM

It's possible with the right tool to rebuild clipped waveforms, but the tools & services are expensive. I have the tools & offer/apply the services all the time on major shows. Not successful on all material but most. A lot of clipping distortion also includes intermod distortion, which is NOT correctable. Often once we cure the clipping, we're left with the intermod, which can sound worse. In these instances, ADR is flagged for the material. If the waveform is squared off but still not at 100%, it just means it was clipped at some prior stage. I see this a lot as well.