Looks fine to me, however, we do offer this product that serves the same function:
http://www.paulcbuff.com/ss1.php or you can get a 3-way (or 4 or 5) headphone splitter at somewhere like Radio Shack (I am sure Amazon and maybe Target/Wal-Mart type places).
Or you can get 2 headphone Y-splitters (single male, double female), place the male end of each into 2 of the Bees. Then run a PC to 1/8 to the first, 1/8 to 1/8 cord from the first to second, and a 1/8 to 1/8 from the second directly into third.
You will, of course, need to make or source your own 1/8 to 1/8 cords.