Wave form Centering?

BobbyG wrote on 6/27/2018, 9:47 AM

I am new to audio editing so please bare with me. I have some old videos recorded on a home video camera. I am wanting to improve the sound quality on these videos of a live band performance.

I have brought the mp4 video into Sound forge 11 on a Windows 10 machine.

The first thing I noticed is that the wave form on both channels are centered on about -5 db. I would like to center both channels to "inf" so that I have some head room to work with to clean it up and increase the volumes.

Can someone tell me how to move both channel wave forms to "inf"?

Thanks in advance.

Bob

Comments

rraud wrote on 6/27/2018, 12:01 PM

If you change the channels volume to inf., you will have no sound at all. You could reduce the files volume to -10dB or so using 'Peak Normalize', (Process menu) then insert a volume plug-in (keyboard shortcut=V) which will give you a variable envelope by adding 'points'. Along with that, I would suggest adding a compressor and peak limiter to the plug-in chain to even things out and to avoid clipping (anything exceeding 0.0 dBFS), The two-stage Wave Hammer plug-in works good for this. Warning: Excessive gain reduction in the peak limiter/maximizer stage will produce muddy sounding distortion.

First though, I would re-save the audio as a PCM <.wav> file (48kHz / 24 bits), When satisfied, save the wave file and then 'save as' an audio-only MP4. You can mux this audio back into the video without re-rendering the picture and avoiding further degradation.

There are lots of muxing utilities available. The free MeGUI always worked good for me. Sound Forge Audio Studio 12 can also replace audio without re-rendering the video.

Note: If you delete (or add) anything in the timeline is SF, it can go out of sync with the picture. If you need to edit, that's best done in Vegas or other NLE prior to the audio work in SF.

BobbyG wrote on 6/27/2018, 3:36 PM

If you change the channels volume to inf., you will have no sound at all. You could reduce the files volume to -10dB or so using 'Peak Normalize', (Process menu) then insert a volume plug-in (keyboard shortcut=V) which will give you a variable envelope by adding 'points'. Along with that, I would suggest adding a compressor and peak limiter to the plug-in chain to even things out and to avoid clipping (anything exceeding 0.0 dBFS), The two-stage Wave Hammer plug-in works good for this. Warning: Excessive gain reduction in the peak limiter/maximizer stage will produce muddy sounding distortion.

First though, I would re-save the audio as a PCM <.wav> file (48kHz / 24 bits), When satisfied, save the wave file and then 'save as' an audio-only MP4. You can mux this audio back into the video without re-rendering the picture and avoiding further degradation.

There are lots of muxing utilities available. The free MeGUI always worked good for me. Sound Forge Audio Studio 12 can also replace audio without re-rendering the video.

Note: If you delete (or add) anything in the timeline is SF, it can go out of sync with the picture. If you need to edit, that's best done in Vegas or other NLE prior to the audio work in SF.

Thanks for the reply Rick, When stripping the audio, do usually leave Vegas open until you are done editing audio and then paste it back in?

rraud wrote on 6/27/2018, 6:07 PM

Does not really matter, unless you are using the Vegas "Open in Sound Forge" (audio editor) mode if it is set up that way. On the other hand, much of the same can be done in Vegas without Sound Forge. Most if not all of the SF plug-ins should be available, and Vegas has it's own Volume envelopes. (same key shortcut as SF)