I am editing on a G3 B/W 350 with a Sony TRV900 with firewire on Final Cut Pro. I get some hot, distorted audio on some clips with louder sound that I digitize from the camera. The camera has automatic gain control so in theory the audio should not be distorted, it also sounds fine straight from the tape on a monitor or phones. Is there a way to check or calibrate my firewire? Is there a way to adjust the gain on digital firewire audio in any other applications (I know that I can't in FCP)?

Any suggestions would be welcome.

-- Joshua Callaghan (joshuacall@hotmail.com), July 01, 1999

Answers

The Sony TRV900 has the ability to be set to Manual Audio Gain. I would suggest that for any shooting in the future. Set it to peak about -5db or so.

For existing footage it sounds like the levels are set too hot in FCP. Maybe checking the audio level part of the manual would help. Otherwise that particular camera's auto gain circuit could be too hot.

Just because a camcorder has Auto Gain controlling audio doesn't mean that you couldn't get too hot audio. Usually the auto gain circuits have a slow ramp up or down so when you get a sudden level increase that it could potentially hit the clipping/distortion/noise threshold.

Auto Gain audio normally will run hotter than good manual settings. DV audio is excellent in the 16 bit mode but it won't tolerate too hot audio.

The best choice is to use good manual audio levels whenever you can. If you can't do that then it would be a good idea to have your auto gain audio circuit calibrated down if you are getting too hot audio.

Michael C

-- Michael C (nospam@hotmail.com), October 24, 1999.