Based on our record, lightnote should be more popular than Interactive Circle of Fifths. It has been mentiond 2 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
It's not quite as powerful, but I've been using the Circle of Fifths tool here on muted.io as a substitute. Source: about 1 year ago
[shameless plug] I built http://lightnote.co for exactly this. Starting from basic sound waves, it teaches music theory while skipping all of the technical notation. It definitely doesn't go as deep as this post, but I don't think that's essential to getting started. - Source: Hacker News / over 2 years ago
My favorite course is https://lightnote.co due to how the information is structured (it's not free though). Source: almost 3 years ago
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