How do I join Sound Investment? Once you've chosen the commission you would like to support, your support can start from a one-off donation of just £20. In return, you’ll receive updates on the progress of your chosen work and and an invitation to a reception at the premiere. For £15 a month (for a minimum of 10 months) you will be invited to rehearsals of your piece and thanked personally in the score. View the commissions you can support.