Here's my opinion about some of them:

Headphones are really just small speakers, because of that the amplifier that drives them is of great importance to how they sound.

When using "audiophile-type headphones" with higher impedance, it takes a fairly high voltage level to get a reasonable volume. The cheap headphone amplifiers in CD players and preamps simply cannot generate the required voltage swing without clipping off the musical peaks.

For the best sound, we must use imo headphones that have 100 ohms or higher impedance. Most high-quality headphones from companies like Sennheiser, AKG, and Beyerdynamic have impedances in the range of 200 ohms to 600 ohms.

Lower impedance headphones, like most Japanese brands, as well as Grado headphones, are more difficult for a head-amp to drive. Their low impedance causes larger amounts of distortion, especially at high volume levels.


So, here's a few headphones i like:

Sennheiser

Sennheiser headphones are imo the best headphones available to the "audiophile". All Sennheiser headphones are good, but my favorite is the HD-600. I think they are flat out the best-sounding dynamic headphones made, especially when driven by a good quality head-amp.

For a little less money, the HD580 is almost the same as the HD-600, at a very attractive price.


AKG Acoustics

AKG is less well-known in the consumer marketplace than Sennheiser, but in the pro audio works, AKG is king. Although AKG makes some great "consumer audiophile" headphones, i like the K240 Monitor headphones, which are part of the AKG professional line. They are a great bargain... they can be found for under 100 €, and they sound great! AKG claims that the K240 is the world's most popular studio headphone, so it's likely that the music you listen to was mastered using K240's....


Beyerdynamic

Beyerdynamic is another European manufacturer that makes headphones similar in quality to AKG and Sennheiser. If you want sealed headphones (that block outside sound) Beyerdynamic makes some of the best. The DT831 is great.


Grado

Grado makes a full line of headphones for the "audiophile". Definitely much brighter sounding (imo), all Grado's have a 32 ohm impedance!!! They work great with only a lower-impedance output amp.



What's your opinion about headphones?

i have found that even todays budget computer headsets can deliver very good sound, even on the low end which i found surprising. the reason i dont enjoy a good set of cans is that the one area where they fall short is the spaciousness, that and i tend to lose the connection to the outside world when i use them.

I concur with you. The last ones i bought were to use with my Ipod (clone) and i'm very content with them. They are hearphones from Koss and cost me less than 20€. A friend of mine have Shure SE110 and they are really great.

For comp use there are some software out there to emulate the lack of spaciousness (even can create virtual surround) that we can get only with real speakers setup.

http://www.iis.fraunhofer.de/Images/ensonido_tcm97-67497.pdf

I have AKG 601s. I use them when I'm trying to escape.

My first pair of phones (1978) were Koss HV/1A's. While they sounded great, they didn't last even two years. Incredibly poor build quality... and I take good care of my stuff.

Then (1981) I got a pair of Sennheiser HD-420's. I still miss them. Comfortable, great sound, affordable. The only reason I stopped using them was that Sennheiser stopped carrying drivers for them... the left one started buzzing.

My present pair (1997) of Sennheiser HD-455's sound pretty good, but not as good as my speakers. They also have a tendency to slip off my head if I bend over. I've already had to replace the headband and ear cushions once; now the only parts still available for them are cushions and adapters. If the band, the cable, or a driver breaks, I'm done for. In one sense, that would give me an excuse to try out some Grados.

All of my phones have been the open-air type. The ones that seal out room sound just didn't sound right to me at all.