Adding -f bestaudio --extract-audio --audio-format wav selects the best audio stream and outputs a WAV file.
Download during off-peak hours (Japan midnight to morning) or upgrade to Niconico Premium ($5/month). Premium mode unlocks high-quality streaming (up to 320 kbps AAC for audio). Hurdle 2: Damon (Nicocas) – The Download Gate Some videos require "Damon" (Nicocas) points or video tickets for download. These are typically anime episodes or exclusive concerts. You cannot bypass this. You must purchase access. Hurdle 3: Login Required for Age-Restricted Content Many Vocaloid songs are flagged as "adult" due to suggestive lyrics or thumbnails. You must be logged into a verified Japanese account (or use yt-dlp’s cookie import) to access them. Part 6: Step-by-Step – Using Audacity (The DIY Standard) If you don’t want to use command-line tools, Audacity is the universal solution. niconico to wav
Remember: Conversion does not create quality; it only preserves what’s there. Start with the highest source possible – preferably a Niconico Premium high-quality stream – and your WAV files will serve you for years of production, performance, and preservation. Have a specific Niconico video you need help converting? Check the r/Niconico subreddit or the yt-dlp GitHub issues page for the latest API workarounds. Hurdle 2: Damon (Nicocas) – The Download Gate