Here's to all the people who want to try out all the mid/higher range headphones before you buy them, and live in the Manhattan / New York area And here we go! :
AC Gears are #1 if you want to try out your headphones before buying them. They have a great selection, and their prices are extremely reasonable as well, either equally matched or cheaper than Amazon. Something you won't have in any of the later mentioned stores.
Some headphones that AC Gears has that you can listen to:
AIAIAI TMA-1 Headphones
Marshall Moniter Over-Ear Headphones (really small and great sound too)
V-Moda Crossfade LP(2?) / V-Moda Crossfade M-100 / V-Moda XS On-Ear
All the Grado's up to the RS2i (Grado SR60i, SR80i, SR125i, SR225i, SR325i, and RS2i) (no RS1i). The RS2i's sounded surprisingly good, even including the fact that I am not a Grado fan of any sort.
Sol Republic Tracks HD / Tracks Air Bluetooth Headphones
Thinksound on1 Supra-Aural On-Ear Monitor Wooden Headphone
Sennheiser Momentum, Sennheiser HD 600, and Sennheiser HD 650.
These are some headphones I remember being there. They also said that they should be getting a shipment of Shure and Beyerdynamic headphones soon, which should be fun
AC Gears even let me use one of their Objective2 amps with some of the higher-end headphones with large amounts of ohms; I liked the Grado RS2i with the amp more than any other combo. Kudos to their customer service.
A small store, with great selection, price, and customer service. Highly recommended!
#2 is Guitar Center, as of right now they have on display the Audio Technica M-50S + M-45, Krk KNS 8400, Beyerdynamic 770 + Beyer 880, Shure 840, and two random ~$200 Sennheisers. A great store to combine with AC Gears for demo-ing. Eager customer service, and great selection of audio equipment in general.
Best Buy and Stereo Exchange are across the street from each other; Best Buy has the Bose and the Beats, as well as the Sony extra-bass series, and Stereo Exchange has Grado's up to the SR325's, but that's about it.
J&R and B&H both have the headphones plugged into the wall with awful music coming out. Only go to those if you have to.
I've heard that Sound by Singer is great, but you need an appointment during their 3-days-a-week office hours.
Anything other stores I'm missing?