Tips for Repairing poor audio lecture recording: Samplitude or Adobe Audition

[Alan]

Hello,

 

I have to attempt to repair a very poorly recorded wav file of a 3 hour audio lecture.  Lots of changes in the volume of the recording throughout, and high pitched noise running in parts of the recording. I have never really done this before, but I have both Samplitude and Adobe Audition and I know they have some features to repair poor recordings.  Any tips on which is the better program to use as I am going to tackle this project as a favor for a friend. 

 

Thanks,

Alan

[S.L.I.P.]

You can try using the spectral editor in Samplitude to remove the high pitched noise in the recording. 

[garybrun]

Izotope RX7 is the best I have found.
Its is on offer,,,  the professional version is amazing.
You can send me a link to the file on PM and I would be more than willing to try and help you.

[Alan]

Izotope looks great but I am going to try to do what I can with Samplitude or Audition.

 

Thanks,

Alan

[mettelus]

Audition helps best if the noise is fairly consistent and you have a places in the recording that are "just noise." For a recording that long, you might need to split it into multiple clips where the noise is fairly consistent throughout the clip duration.  For each clip, you would want to highlight a section in the timeline that is only noise and then "Capture Noise Print" (Shift-P), then click in the timeline so that nothing is selected and "Noise Reduction (process)" (Ctrl-Shift-P). I would start with the default settings on that confirmation dialog and see how it works.

You can also capture a noise print off the Spectral Display (if is it only high frequencies, or such) and remove it similarly. Additionally, you can also highlight the section you want to remove noise from in the timeline to apply the removal process to (saving you splitting the recording), but I am not sure how intensive the process would get with that entire file open. You may need to save it as a copy first to test that out. You may also want to save frequently or reduce the number of undo history it tracks (my version is older, so I cannot adjust this). Working with a file that large may start consuming RAM on you otherwise.

Edited February 27, 2020 by mettelus

[Michael Vogel]

Make a copy of the file before you start doing any editing.

[Byron Dickens]

Oh yeah.  Definitely work with a copy!

 

You also can often get much better results by doing only a little bit at a time in multiple passes.

[paulo]

13 hours ago, Michael Vogel ( MUDGEL) said:

Make a copy of the file before you start doing any editing.

[craigb]

22 hours ago, Michael Vogel ( MUDGEL) said:

Make a copy of the file before you start doing any editing.

 

9 hours ago, paulo said:

[John K]

Friends,

Throwing in another option. Have used by default Audition, but stopped upgrading after ver 3 so don't know if they got it any better.  Totally igorant about other pathways suggested.

Reaper DAW has a native plug called ReaFir.

Has several functions, but after loading the offending wav onto a track in Reaper, select the "subtract" option.  Then make sure the "Automatically build noise profile" is checked.  Similar to the Audition approach as far as I can tell.

Go in and take out the background noise. As with any others, more time to analyze pure noise makes the result more accurate.

Problem as most know is that noise shares bandwidth with valid audio you want to keep. More noise you take out, the more wanted audio is taken out as collateral damage. There's where you have to back off any analytic noise reduction algorithm to a compromise of noise reduction versus losing the good stuff..

Have had some moderately good results by stripping out a nominal amount of noise and then going back in with a harmonic exciter to toss back in a bit of selective high end lost in the noise extraction. Also has to be done carefully and with craft to not sound like you got some slapback hi freq distortion on the track.

Last thing I used as a freebie after tearing up a file with Reaper was this free plug. Thrillseeker XTC  Somewhere on the page.

https://varietyofsound.wordpress.com/vst-effects/

Best I know about how to deal with really forked up restorations. Couple step process but possible as good as we can do currently. Fully envision up the line a near perfect noise abstraction software. Most of us will probably be pushing up daisies before that happens, but will happen.

John

[Jim Roseberry]

With "Noise-Print" style noise-reduction, you may achieve better results using several passes (at lower reduction settings)... than using a single pass with heavier reduction.

If the noise is almost as loud as the desired audio, it's going to be tough to achieve significant artifact-free noise-reduction.

 

 

[John K]

Jim

Thanks for this tip on multiple lower reduction passes.

John

[Byron Dickens]

I was there first!

[bitflipper]

If this was a paid gig, I'd say go out and buy iZotope Rx. But given that it's a freebie, Adobe Audition should do OK. It has decent noise reduction features, and its spectral editor can handle the one-off noises (be ready to spend some hours with your headphones on). As Jim points out, it will probably require multiple passes. Fix the noise first, then use LP and HP filters to narrow the spectrum to just the speech frequencies, and finally work on the amplitude issues with gain automation, gating and compression.

[Alan]

Thanks that's great advice.