Sound Restoration


Q I have a video project that I’m working on as the sound mixer, and I’m serving as the audio editor, as well. I had some equipment issues, however, which resulted in audio tracks that were noisy and hissy. This was a one-shot deal for a documentary, and it can’t be rerecorded, so I need to do the best I can with what I have, which at this point is just an old copy of some basic audio-mixing software. What software do you recommend for audio repair?
Glenn L.
Via email

A You’re in a tough position because, normally, poorly recorded audio is difficult, if not impossible, to "fix." You’ll probably never move your bad audio to the good category, but there are some innovative audio repair tools available that will minimize some of the issues.

One software package I recently had a chance to use for a project that had sound that was similar to yours (lousy) was iZotope RX™ 2. I hadn’t needed serious audio-repair software for quite a few years because I’ve been very careful to either record quality audio myself when I’m the sound mixer or I’ve been diligent in hiring highly talented sound mixers who almost universally deliver good quality audio.

I’ve also been in your position, though, where a piece of gear has given me trouble and the resulting audio leaves much to be desired. iZotope RX 2 is an entire software suite of sound-restoration tools that includes Denoiser, Decrackler, Declipper, Declicker, Hum Removal, MBIT + Dither, Radius Time/Pitch and 64-bit SRCTM Resample.

I would suggest going to the iZotope RX 2 page for a complete detailed rundown of what each of the modules does, along with before-and-after samples, at

So, what does the software actually do? iZotope RX 2 enables the removal of noise, hiss, buzz and hum, eliminates clicks and crackle, restores clipped audio, visually selects and suppresses unwanted sounds, resynthesizes missing audio and quite a bit more. The package is feature-packed and it will take you a while to master, but it’s simple enough that you could purchase it and probably obtain some decent results by just watching some of the video tutorials on iZotope’s website and on YouTube.

I was able to load up some poor- quality audio into RX 2 that I had recorded a couple of years ago with some bad cables with loose connections. On top of an occasional cable crackle, there was a lot of HVAC sound mixed in with a man’s voice in an interview, and there were occasional traffic sounds mixed in with the audio, especially some low rumbling of trucks from a loading dock that was located about 10 floors below the high-rise office I was shooting in.