So turn off the lights, light a candle, and have a seance
Possibly a case of double entendre her. Turning off the lights and lighting a candle to have a seance could mean ignoring all the flashy aspects in order to focus on one thing. The truth in this case.
This line could also mean that in order to speak to the dead, you need to lose all distractive elements to focus on your sole purpose which is getting in touch with the dead through a seance. The seance here being the music.
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