I've listened to both of them and can confirm this, the JVC's treble is extremely harsh at high volume levels. At lower volume levels it isnt too bad, but it's still there.
I feel as if the Phillips isn't bassy enough for a "basshead" earbud IMO. It does have great low frequency extension and quantity, but doesn't have enough impact. I do feel It's SQ is the best had for under $10 though.