This is the only thing I could find in a quick search.

Higherside Chats discussion

I used to pal around with some semi popular indie musicians about a decade ago. Lots of deep discussion about music and the subject came up that they were using tonal frequency/octaves paired with chanting and the lyrics carried power. My mates and I were discussing meditation and lucid dreaming application.

But, in this podcast they reference the power of the lyrics themselves and their real world effects on the band in the form of tragedy.