Headphones

I have the 580s which I use with my portable audio with the entry level headroom amp. Definitely better than the 500 I used previously. I tried the 600s in the recent NY show with several amplifiers and despite the reviews I was not sufficiently impressed to buy them. In my bedrroom I use the Beyerdynamic 931 which are excellent and so far not reviewed in USA. Amp is Wheatfield HA2 but the much cheaper Antique sounded good also. I find that the 931s reproduce very well the extremes of the audio spectrum while having an accurate midrange.

I have and really enjoy the HD-600's. Excellent for Jazz and Classical as well as accoustical music. Very comfortable. If you like aggressive sounding (forward placement) sound (especially rock) and can stand the way the Grado fits on your head (I find it very uncomfortable), that may be a better fit for you.

The typical comparison between the two is generally as follows:

Listening to the Senns is like listening in the 10th row center of an auditorium. Listening to Grado's is like being on stage with the band/orchestra. Grado's are very dynamic but I find them a bit fatiquing and a bit colored. Others find them exciting and the Senns too layed back.

As for electronics, I greatly prefer tube Amps with my headphones. The MG-Head by Antique Sound Labs is a very good buy at about $275.

Good luck.

The best thing you can do is to audition as much stuff as possible.

The HD600 is really nice but I prefer the Grado RS-1. I don't like way the HD600 smoothes over all recordings good or bad. When the album has bite, I don't want a filtered out kind of distant rendition. You can get a very comfortable fit by bending the headband and tossing the earpads in the washing machine with some hair conditioner.

As for headphone amps, they range from $99 to $5000. Poor to astounding. I didn't really find anything to my liking until I broke the $700 barrier. Lower priced tube amps were seriously flawed in one way or the other.

I have lower priced Grados and old Stax lamba's at home, so I can't help you there

If you are interested in headphone amps and have an interest in a great fully functioning tube preamp, try out the SOnic Frontiers Line 3, (or 2 or 1) it has the Headroom circuitry headphone amp stage and is one of the most neutral preamps on the planet. Great detail and neutrality in a fully functioning preamp. Check out the reviews on their website, the Soundsatge review included the Sennheiser interfacing with this headphone amp.

Headphones are a very personal decision as not only sound quality but comfort is involved.
You can spend hours reading posts here and at headphone websites debating about whether Sennheiser or Grado is "better" and will probably find no conclusive proof either way.
They are both good.
I have tried Senn. 580's at home and have listened to the 600's in various dealers.
However, my personal preference is for the Grado RS-2's.
I do not like headphone amps. I have tried 3 different models, tube, solid state and hybrid and none were much better than the headphone output of an NAD receiver. I should qualify this by adding that the NAD sounds better than the headphone outputs on any cd player or tape deck that I have tried. I have gotten more bang for the buck by upgrading headphones and my cd front end than from a headphone amp.