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Students’ Leaf Blower Suppressor To Hit Retail
(hackaday.com)
This is a most excellent place for technology news and articles.
Reading the article, reducing the shriller frequencies by 12db is still pretty nice, looks like it's designed for electric blowers which are already way quieter than gasoline powered ones, already generally in the hearing safe range. 2db overall should still be noticeable though, be generally less annoying.