“Add Some Music to Your Day,” The Beach Boys’ paean to the power of music, anchored the group’s 1970 album Sunflower.   The song’s imagery conjures music from the seemingly mundane to the undeniably transcendent, expressing the belief that “the world could come together as one/If everybody under the sun” would add some music to their day.  Now, the gentle, uplifting Brian Wilson-Mike Love-Joe Knott anthem is anchoring a new album for a very worthy cause. On April 23, Omnivore Recordings will release California Music Presents Add Some Music, featuring the participation of…