Trouble with background static and frequency limit in Audition

[Joseph W. bourke]

From the looks of the waveform, the audio was recorded at way too high a level, and there’s massive clipping going (the flat cutoffs at the top and bottoms of the waveform). You can’t get back what is gone, and the hiss and background noise is probably a result of not setting gain properly. You could try lowering the volume, and normalizing, but I don’t think you can save the quality much.

Better to do some test setups for the next phone recording session to make sure you’re getting levels right, and write this one off as trashed.

Joe Bourke
Owner/Creative Director
Bourke Media
http://www.bourkemedia.com

[Margot Lawton]

Thanks for the quick response. I should have been more clear that I’m only interested in the audio that has the clipping. The other audio is my voice and I can re-record. Is there a way to prevent that clipping from occurring? And should I be setting the gain differently on my digital hybrid box or in Audition? Thanks!

[Joseph W. bourke]

From listening to it – it also sounds as if there’s maybe car noise in the background. Was the person driving while talking on the cel phone? If so, and you have a section where no one’s talking, try getting a noise floor sample, then removing that from the clip. It might help a bit…

Joe Bourke
Owner/Creative Director
Bourke Media
http://www.bourkemedia.com

[Durin Gleaves]

Hi Margot,

Typically, telephone signals are limited to between 300Hz and 3,400Hz with everything above and below stripped, so it’s unlikely there would be any additional data to capture. The background is rather noisy, and while laptop speakers generally have poor output which masks these sorts of problems, quality headphones will certainly expose any flaws in the recording. I see Joseph recommended a noise reduction pass, and I agree that locating a short region of audio that consists only of noise and no speaking, and capturing this as a noise print to use with the Noise Reduction effect, will go a long way toward making the speech portion of this recording sound better.

—
Durin Gleaves
Adobe Audition

[Margot Lawton]

Thanks Durin,

Two follow up questions. Generally, when I do a noise reduction, the end result sounds warbled. Is there any way to prevent this? Also, is there a way for me to record better quality interviews over the phone? I’m just trying to figure out if my problem has to do with the settings on my digital hybrid box, audition, my soundcard, or my phone. I’ve spent hours playing around with it, but with so many variables, I’m not sure I’m ever going to make progress. If you thought you might be able to point out a likely source of the background noise, it would be super helpful. Thanks so much.

[Joseph W. bourke]

As Durin said, the phone is most likely one of the main culprits – they’re designed to drastically limit bandwidth so as to be easy on resources. They are barely an audio device…

I think you can start narrowing down the problem by starting with the simplest setup – record with that – add a second piece of your equipment – record that…and so on, then compare your recordings to see where the problem first shows.

As far as using the noise floor removal…you can tell Audition how agressive you want the removal to be – experiment with that, and you won’t get the warble. That happens when the voice and the noise are in the same part of the sound spectrum.

Joe Bourke
Owner/Creative Director
Bourke Media
http://www.bourkemedia.com