Yep. I have the Senn 650's and unless used with an amp are underwhelming. That's what the Klipsch s4i's are for.Headphones - Bose 15's
Earphones - Klipsch X10i's and S4i's
Sometimes I'll use my Sennheiser 800's or 650's, but they don't sound too great without an amplifier on em'.