I reviewed the Sennheiser PX 100 headphones last year and really liked them. I had gotten the Koss PortaPro’s about the same time, but hadn’t really used them much. Listening to the PX100’s at work for extended periods of time started making my ears hurt (maybe I have sensitive ears) and replacing the pads didn’t improve things much, they’re still clamping down on your ears to stay in place.
The Koss PortaPro’s feature a “Comfort Zone” that places an additional pad above your ear where it can be set to transfer most of the “clamping” feeling from your ears up to the side of your head. This makes the PortaPro the most comfortable open, over the head headphones I’ve ever used. Ear discomfort is gone and I’m able to wear them for extended periods.
Along with being comfortable, they sound great. In fact I think I like how they sound better than the PX100’s. The PortaPro’s pump out some very nice low end while staying balanced and clear. The PX100’s are a little more laid back and sound darker. The PortaPro’s just have that extra bit of punch.
As of this writing the PortaPro’s are $32 at Amazon while the PX100’s are $50. Between the comfort, price and sound quality of the PortaPro’s they are easily my favorite headphones now. They definitely get my sound geek stamp of approval.