If you want to have fun editing your audio and music files, then a good choice is Fx Audio Editor Pro 4.1. It is a complete editor that also comes with its own integrated player, a recorder and converters between different audio formats.
Apart from the usual sound mixes (between different types of audio formats) you can add diverse types of effects and filters to the sound files you generate, like retard, normalize, amplify/minimize volume, play the track backwards, noise reduction and optimization filters, reverb, etc.
For it to work correctly, the program needs DirectX 9.0 or later installed first. If you don`t have it, you can find it here
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