Audio Downloader is all you need to extract high-quality sound from YouTube.

Features:

Easy to use
No need to install
Portable
Runs from USB flash drive
Automatic updates
Intuitive user interface
Window always on top
Downloads audio in high-quality
Mp3 audio quality can be selected
Playlists support
Displays current download speed
Uses Youtube-dl for downloading and FFmpeg for processing
Allows usage of Youtube-dl command line interface
Can store information about the download in Google Sheets (option)
Open source

Audio formats:

WebM (Opus) unprocessed raw audio
Opus unprocessed raw audio
AAC (m4a) raw audio
Vorbis unprocessed raw audio (if available)
FLAC lossless compression
Mp3 VBR lossy compression