I did both together this afternoon(Biotuner 7.83 hz and mp3 7.83hz) It was actually kind of cool because the beats in the music matched the biotuner's so well..it was really a different experience. Anyways, I fell into a very very deep meditative sleep..it was almost an out of body experience. I ended up falling asleep somewhere around the 10 minute mark and didn't wake up until it was over (the mp3 is a little over 18 minutes/20 minutes Biotuner). Upon waking up I felt very groggy and dopey. I was disappointed that there was no euphoria at all (maybe because I only used it for 20 minutes?) I had to go lie down again right after, and fell into a very very deep sleep for about 1 1/2 hours.
The addition of the sound, really changed the experience
of just the biotuner alone. I think this would be very powerful for insomniacs to use just before bed.
I can't imagine what light would add..it might be too overwhelming!!