When Bob Macafferty got kicked in the head by an epileptic horse in 1978, he almost died. He did not come out of the coma for 2 months. He awoke in early '79 with tales of singing with the angels in heaven's waiting room. He integrated a device into his electric guitar in an attempt to recreate the sound of the angel voices. He called it a "hark" after the famous Christmas carol that says that's what angels sing. No one else has been able to get it to work and the secret died with him in 1992.