We recently ran a shootout comparing low cost noise reduction tools. The shootout featured four pieces of problematic audio, each exhibiting a different problem; hum, crackle, clipping and general broadband noise. The noisy audio was processed with five different noise reduction tools:

• iZotope RX Elements consisting of De-hum, De-click, De-clip and Voice De-noise

• Acon Digital Restoration Suite 2 consisting of DeNoise2, DeHum 2, DeClick2 and DeClip2

• Acon Digital Extract:Dialogue

• Waves Clarity Vx standard edition

• Antares Autotune Soundsoap

The results were randomly labelled A to E. We asked the Production Expert community to blind listen to each piece of processed audio and vote on which they thought sounded the best.

The results are in…

Test 1 - Hum

Example A was iZotope De-Hum

Example B was Waves Clarity Vx

Example C was Acon Digital DeHum 2

Example D was Antares Soundsoap

Example E was Acon Digital Extract: Dialogue

Test 1 poll winner: Antares Soundsoap

Test 2 - Crackle

Example A was Acon Digital Extract: Dialogue

Example B was Antares Soundsoap

Example C was Waves Clarity Vx

Example D was Acon Digital DeClick 2

Example E was iZotope De-Click

Test 2 poll winner - Acon Digital Extract: Dialogue

Test 3 - Clipping

Note that only 3 of the 5 noise reduction tools were used for this test because the others don’t provide de-clipping

Example A was Antares Soundsoap

Example B was Acon Digital DeClip 2

Example C was iZotope De-Clip

Test 3 poll winner: iZotope De-clip

Test 4 Broadband noise

Example A was Waves Clarity VX

Example B was iZotope Voice De-Noise

Example C was Acon Digital Extract: Dialogue

Example D was Acon Digital DeNoise 2

Example E was Antares Soundsoap

Test 4 poll winner: Acon Digital Extract: Dialogue

Noise Reduction Shootout Results Summary

Based on the results of this test, as voted for by the Production Expert community, the most effective tools for reducing each type of noise were the following:

Best hum reduction: Antares Soundsoap

Best crackle reduction: Acon Digital Extract: Dialogue

Best clipping reduction: iZotope De-clip

Best broadband noise reduction: Acon Digital Extract: Dialogue

How Was The Test Conducted?

With a test like this it’s inherently difficult to do a completely like for like comparison between different tools because the way the plug-ins quantify the amount of noise reduction differs. Some specify a value in dB, others, such as Waves Clarity Vx have a dial which goes from 0 to 100 but doesn’t give a specific value for how much you’re actually reducing the noise by. For that reason I chose to push each plug-in as far as it could reasonably go before introducing too many problems with artifacts. Consequently, the amount of noise reduction differed from one plug-in to another, reflecting how much I was actually able to push each one. Some allowed for a greater degree of noise reduction than others. Many of them struggled with hum removal, only kicking in just after the hum had started and so leaving a brief burst of it at the start.

What Do The Results Tell Us?

In two out of four cases in this particular test, Acon Digital Extract: Dialogue came out top. It was voted best for broadband noise reduction and best for reducing crackle. In the crackle test, another one of Acon Digital’s noise reduction tools, DeClick2 came a close second. iZotope De-clip was deservedly voted best in the clipped audio test and Antares Soundsoap came out top for hum removal. This was the only one of the hum removal tools which didn’t leave a small portion of the hum audible at the start of the file.

Based on these results it seems that there is currently no single cost effective noise reduction solution which provides the best option for all types of noise. Having more than one option at your disposal for noise reduction is a good idea, particularly if you’re working on dialogue. I’d like to give a special mention to the contender which didn’t come out on top but which nevertheless gives very impressive results with minimal effort, particularly for the removal of broadband noise and that’s Waves Clarity Vx. For ease of use, this is hard to beat.

In The Interest Of Fairness

One thing to remember about these results is that this is a single test with just four different pieces of audio. To get a totally fair and accurate idea of how these plug-ins stack up against each other we’d need to listen to many more examples. In everyday use you’re likely to encounter a range of noise problems of varying kinds, and exactly which tool gives the best results can vary from one project to another. Having different noise reduction plug-ins available to you as you work allows you to switch between them when needed and choose the one which provides the most effective noise reduction at the time. All of the plug-ins have demos available so try the different tools out for yourself and see which one(s) fit your own needs best.