What's wrong with say Spotify Free? Sure you get some ads, but I find the quality quite acceptable for non-critical listening.

Perhaps OP is too used to the Beats one-note bass sound signature? The Momentum certainly doesn't deliver if what you're looking is more one-note bass.

Disclaimer: I'm firmly in the camp of cables make no difference. Scientific evidence to date suggests no audible difference from one cable to next. There's the Sound Science forums if you want to learn more about the details. If you are one who finds that a custom cable will open up the highs...

Quote: +1   Sometimes I like to annoy the hell out of my lab members and take my HD650s.  I drive them from the Total Bithead USB DAC/AMP or straight out of the Macbook Pro output. Both sound equally good and I don't even use up 3/4 of the bars on my Macbook Pro which means there is...

Quote:   I see a pair of D2000/D5000 or two pop up on Buy Sell Trade every week. And then there is eBay...

If you don't mind used/refurb. Add Sennheiser HD280 Pro to the list. Crazy comfortable and super durable. I've carried them in my backpack for 3 years and I don't baby my backpack. It gets sat on, thrown around, etc. Also fallen asleep at the desk with them on many times. Should be able to...

I think what OP was getting at is that common people judge headphone quality by the amount of bass they produce. It's a bit like judging how fast a car will be using only its horsepower rating. Things like a wide usable power band, a good tranmission, and grip contributes to a fast car around a...

I own both Sennheiser HD600 and HD650. If you're going to buy one of the Sennheisers for rock/metal. I'd suggest the HD650. The bass really isn't really there enough on the HD600.

I don't think Sennheiser has many "bad" products. They're all pretty much average for their price or better. It's just that their "good" products just make the average ones look bad. If there was one company that I'd recommend to buy a headphone from without specifying a model, it would be...

Quote: I own a HD600, HD650 and a K702 and can confirm this. Everything sounds so muddy without an amp.

This is similar to the "stockings" mod for the HD6xx. With the HD6xx, it makes a world of difference though since their foam is as thick as a pancake.   In this case with the HD558 protective mesh, it's so thin that very few people, if any could tell the difference.

Pretty much everything in my profile I've fallen asleep with on. Comfort is a very big factor for me.

Except for the headband pads, these look more like a HD 650 than a HD 600 in its current form.   Can I get a 2880x1800 to use as a wallpaper on my Retina Macbook Pro? ;-)

I would suggest investigating other sound signatures like AKG, Beyerdynamic, Shure, Grado, etc.... before spending another $200 on what is probably an insignificant upgrade.   In fact, a lot of people prefer to have different cans for different genres of music.