Noise Reduction 2

Since the introduction of Dolby in the 1960s, noise reduction has played an important role in the history of recording. The battle against analog tape hiss and background noise has seen four types of Dolby noise reduction, many hardware noise gates and now PC software.

The advent of digital recording hasn't dispensed with the need for noise reduction; there's still background noise from microphones, effects units and guitar amplifiers to take into account, as well as trying to get the best out of old analog recordings.

At a price of £234 Noise Reduction 2 seems expensive, but Sonic Foundry claims it performs as good as or better than hardware systems costing thousands of pounds, offering amazing value for money. There are four main features to the software - noise reduction, vinyl restoration, click and crackle removal and clipped-peak restoration. Given that this is a DirectX plug-in, you'll need a DirectX audio-compatible host application to run it. I tested it on Sonic Foundry's own Sound Forge 4.5, but you could also use it on Cakewalk, or another professional music package supporting DirectX.

The previous problem with noise reduction such as Dolby or dbx was that it only worked if the original was recorded with the same noise-reduction system - otherwise it had a tendency to sound dulled and over-compressed. I expected the same effect from this program but was pleasantly surprised. The noise reduction plug-in can actually eliminate the hiss on even the noisiest tape recordings completely. However, an extreme amount of noise reduction will still dull the recording. This happens because the system eliminates high frequencies such as hiss, and hence also removes high frequencies in the music, making it less dynamic. However, adjusting the controls can provide a good compromise, especially as you can use one type of noise reduction for a loud part of a recording and a different type for a quieter section.

You also have a lot of control over the amount and shape of noise reduction, from the standard attack and release-time controls to noise bias and envelope amplitude, with graphs to show the shape of the noiseprint envelope, which is adjustable on screen. You can also preview how it will sound while adjusting the controls in real-time, giving all the control you need before affecting the whole recording.

The prospect of vinyl restoration at this price seems an amazing feat, especially if you're a vinyl collector like me - the next amazing thing is that it actually works. Like noise reduction, the end result depends on the quality of the original. However, I found that quiet tracks, previously destroyed by pops and crackles, sounded reasonable again after using this plug-in, and comparing the restored file with the original afterwards demonstrated how effective it was. It won't make your records sound like CDs, but it will make them usable again.

Noise Reduction 2 is an impressive package, providing professional-quality noise reduction at a price that's more affordable than racks of noise gates and compressors. The vinyl restoration feature is a particular favourite, providing studio-quality audio processing to the PC for an amazing price.

Author: Ben Hardwidge