I was in a similar position a number of months back. I started reading the posts on this forum, going back many months looking for good advice on headphones. I was trying to upgrade from a pair of 25 year old Yahama YH-1 headphones, and was not sure where to start.
I think you should be able to get the headphone/amp combination that meets your needs within your $500 budget.
You did not state whether you want the headphones to be fully sealed, partially sealed, or open designs. The fully sealed type isolate the listener from outside sounds and also don't leak sound into the surrounding area to disturb other people. Many of today's top of the line headphones are open designs, that offer little sound isolation for the listener and leak sound, at least a little bit.
Here is my short list of headphones that you should consider, prices are estimates:
Sennheiser HD-580: $140
Sennheiser HD-600: $240
Grado RS-1: $500
AKG-K1000: $500
With most of these, you are going to want to get a dedicated headphone amplifier to get the best sound from these, although any of them will provide adequate levels of volume connected to your Denon, all except the K1000s. These require an amplifier of at least 10 watts/channel @ 8 ohms, as these headphones are actually miniature loudspeakers that hang just to the side of your head, and slightly off of your ears.
The reasons to consider getting a headphone amplifier include:
- Improved clarity at all levels
- Improved bass response: deeper, tighter, more extended bass
- Better dynamics, able to respond to momentary musical peaks with very realistic, unstrained audio output.
Also, some amps include special circuits for crossfeed. You can read about the goal and benefits of crossfeeding portions of each channel to the opposite ear here and especially on the following site:
www.headphone.com
This site is also an excellent source for technical specifications on a number of different brands and model of headphone.
You will read alot of information on this board about upgrading headphone cables to improve the sound of certain models, especially the HD-600s. I suggest that you pick the headphones, then research getting a good amplifier, before worrying about replacing the standard cables.
What did I decide to get? Thats easy, HD-600s. I am very satisfied with my purchase. I did not need an amp because I power them through vintage solid state and tube powered integrated amplifiers and especially a Fisher tube powered receiver.
Sometimes I have need to plug the HD-600s into my Denon DCD-1500 CD player (circa 1986) or my Denon DRM-710 cassette deck(circa 1991), both can provide adequate listening levels, but fall way short of the listening experience of combining the HD-600s with one of my amps or receivers.
If you have ever been curious about the merits of tube audio, but did not want to deal with the cost, space, cooling requirements of tube gear, look into getting a tube powered headphone amplifier. You can get all of the benefits of tube audio sound without the burden of high costs, large heavy tube power amplifiers, and a thermal output can that help heat your home. There are some new manufacture tube amplifers made specifically for headphones can be purchased new for under $500, even less if you buy used.
There is alot of good information on this board about both tube and solid state amplifiers for headphones.
Good luck and let us know what you ultimately decide.