Noisebud Skyline is easy to use the multi-band image editor for mastering.
You can easily enhance or create depth in a track with the quick and easily accessible controls and you don’t have to worry that you push it too hard since whatever you do with Skyline you can’t break the mono-compatibility. Skyline consists of three main controls, Spread, Pan and Width. ‘Spread’ will either enhance the ambience by using the information in the difference channel and spread it out in the stereo-field, or use the information from the sum-channel and spread that out in the stereo-field. The latter is great if you want to up-mix a mono-file to stereo. ‘Pan’ will pan the audio in the selected band and ‘Width’ will either boost the sum or the difference by 2dB without touching the other channel. Watch the video, preferable with headphones to get an idea of this little gem.