Chaturatma: One night there was a darshan with one musician. I never got the understanding whether this was a person coming to Krishna consciousness or this person was already a devotee. Anyway, this was someone who wanted to use his western rock and roll guitar style in service to Lord Chaitanya. Prabhupada was very adamant and the guy kept bringing the point up two or three times and Prabhupada finally said, "No." He pointed to a beautiful picture of the Panchatattva on the wall of his room and said, "You see Mahaprabhu, kartals and mridanga. That's all."

From Srila Prabhupada Remembrances ch. 51