The Seattle Symphony will be offering free livestreams of their concerts on their Facebook and YouTube pages during the current pandemic. Check this site for times and dates, and for direct links to their social media pages.
NPR's Tiny Desk Concerts are intimate performances recorded live at the desk of "All Songs Considered" host Bob Boilen. Artists range from the well-known to the off-the-beaten-path.
NPR's YouTube channel features jazz concerts and their NPR Music Front Row series, which features live concert recordings of contemporary artists from venues across the country.
The Berliner Philharmonie is offering free access to their Digital Concert Hall now through March 31 with the voucher code "BERLINPHIL." The Concert Hall features hundreds of recordings from current and past seasons.
A site offering live concert recordings from around the world. A selection of the operas and concerts on medici.tv are available for free with a guest account.
Click on "log in" to create a guest account, then browse their concerts
The Metropolitan Opera will be streaming encore presentations from their "Live in HD" series for free during the coronavirus closure. The schedule and link can be found here.