I like that idea MUCH better, as $60 for that seemed a little pricey. But what do you put under the sheet, earphones/buds or actual headphones?
I don't really care for lucid dreams, so I won't be trying it.
Assuming that your talking about my post of the under-pillow speakers... (That's where they're designed to be placed.):
1) They're $29.95 from that site. (Where did you get $60 ?!?) But watch out for S&H $$ !
2) They're not ear-type devices at all. They're FLAT (5/8"-thick, ~4" square)
speakers, which - despite what you might think about that spec' - might sound very good! (The ones that I had were about that size, too, and being under you pillow has two advantages: their size really doesn't matter, and strangely - the tone is excellent! (Again, your mileage may vary with the specifc speaker/product.)
So NORMALLY you simply lay out the speaker "strap" under your pillow and run the cord out the top and around to your source.
However, I'm a face-down pillow-hugger, so I woulda made a mess out of even THAT arrangement! Soooo I put the thing right on top of the mattress, and then made the bed (with the mattress pad & bottom (fitted) sheet over the whole affair) as if the speakers were built into the mattress itself.
I never had a problem with that arrangment at all.
'Hope that answered your questions!
P.S.
Here's a Google search link for more info and other purchase sources.... (They go for $19 @ Amazon from multiple sellers.)