The other sliders work in tandem with Denoise: Enhance restores treble or "sparkle" at the high end that may have been lost, while Boost performs double-duty, raising the volume level on quiet recordings, or clamping down on any clipping with audio recorded too loud.
My only real complaint is that VideoSoap hasn't yet been fully optimized for either Retina or iPhone 6 displays. I'd also love to see extension support that would make it possible for VideoSoap to act directly on existing Camera Roll files, replacing only the soundtrack while leaving the video intact without having to create an entirely new file.
VideoSoap is a must-have for iOS videos recorded in noisy locations, with similarly impressive results as the desktop version distilled into a mobile app that's easy enough for anyone to use.
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