I already own the d340. i am looking for an upgrade. you think the momentums are an upgrade to them?i've owned the Sennheiser Momentums and the Denon D340 (well technically still own them, I just let my sister borrow them). The D340 is very smooth. The highs are nowhere near harsh and the bass is pretty boomy. The mids are recessed but not as recessed as the D1100. The Mommentums are also smooth, non fatigue but with lots of clarity. I would definitely recommend the Momentums over the D340.