The Berlin Philarmoniker (their orchestra) is giving out free access vouchers until the 31st. All you need to do is make an account, they don't even ask for payment details.
"The Digital Concert Hall now free for everyone
The Philharmonie is closed – so we will come to you! Redeem the voucher code BERLINPHIL by 3/31/2020 and receive free access to all concerts and films.
https://www.digitalconcerthall.com/en/home "