In order to minimise audible artifacts, specifically tonal changes, the fader should be pulled down only far enough to bring the ambient sounds down to an acceptable level. When the signal drops below each band's threshold, it is subjected to gain reduction. In other words, it is assumed that over a certain level the noise will be masked by the main audio. The noise‑reduction process depends on the level of signal in each band, so when the signal exceeds the processing threshold, no gain reduction is applied.

There's no metering or display on the interface, so the setup procedure is to start with the master Threshold control at zero (corresponding to ‑39dBFS), then pull down the slider or sliders that encompass the frequency range of the unwanted ambient noise. It's recommended that W43 be inserted before other dynamics plug‑ins, such as compressors, which may otherwise further increase the level of noise. The frequencies are separated into Low (30Hz to 80Hz), Low Mid (80Hz to 1kHz), High Mid (1kHz to 3kHz), and High (3kHz and above). Waves also state that the plug‑in introduces no additional latency, so dialogue sync will not be affected.Įach of the four frequency-band sliders sets the amount of noise reduction applied to that band. W43 isn't intended for broadband hiss removal its primary function is the reduction of continuous, low‑level ambient sounds with the minimum of audible processing artifacts. Just like Dolby's original Cat43, the W43 noise reduction plug‑in is very simple to operate, having only four fixed frequency‑band sliders, plus a master Threshold slider. It's the second tool from Waves aimed at controlling troublesome noise, and joins the more expensive and complicated WNS (Waves Noise Suppressor). The plug‑in is available separately or as part of the current Mercury Bundle. The Waves W43 supports up to 24-bit, 192kHz resolution and is compatible with both Mac OS and Windows PC platforms supporting TDM, RTAS, Audio Suite, VST and Audio Units formats. Now Waves have set out to make the Cat43 solution a little more convenient and readily available by emulating its features and functions in software form. One long‑standing hardware solution is the rare Dolby Cat43, which is a spin‑off of Dolby A noise-reduction technology (see 'The Dolby Cat43' box). Camera 'whine', air conditioning hum and distant traffic rumble are all exampes. One of the biggest problems faced by engineers when recording audio for video is ambient noise. Video makers need to reduce noise too - and W43 lets them do it in time-honoured style.

Use waves x noise