There are several free audio editors available that are reliable and offer powerful editing capabilities. Here are some of the best options:
Audacity:


Audacity is a popular open-source audio editing software that is free to use. It offers a range of editing tools, including noise reduction, pitch correction, and audio effects.
Ocenaudio:


Ocenaudio is a user-friendly audio editor that offers real-time preview of effects and plugins. It also supports multiple file formats and has a clean and simple interface.
WavePad:


WavePad is a versatile audio editing software that is available for free for non-commercial use. It supports a range of audio formats and offers advanced editing tools like spectral analysis and noise reduction.
Ardour:


Ardour is a powerful digital audio workstation that is open-source and available for free. It offers multitrack recording and editing, MIDI support, and plugins for advanced processing.
LMMS:


LMMS is a free open-source digital audio workstation that is designed for music production. It offers a range of tools for composing, arranging, and mixing music, including support for MIDI and plugins.
All of these options offer a variety of editing tools and features, so it’s worth trying out a few to see which one suits your needs best.