GoldWave is a powerful audio editor that comes packed with high-end processing features.
A lengthy list of effects allows you to tune audio with the equalizer, adjust pitch, add reverb and echo, reduce or even remove vocals (depending on the recording), tweak audio volume, and more.
You're able to clean up old analogue recordings with filters to remove noise, pops, hiss, crackles and clicks. The Spectrum Filter delivers fine control over tone. And it's easy to trim digital files, removing silences to concentrate on the music.
A comprehensive batch processing tool will convert files to and from just about any audio format: MP3, WMA, OGG, WAV, AIFF, FLAC, XAC, IFF, AU and many other file types are supported. And it only takes a few clicks to build other GoldWave commands into the mix, so you could automatically process an entire folder of music files in just a few seconds.
GoldWave also works well as an audio player; includes a capable audio recorder; and it's full of surprising bonus features. So the Speech Converter, for instance, leverages Windows own speech tools, converting text to spoken audio files.