Advice on new headphone system please

I spent well over ten years developing and upgrading my headphone system to where it is now. There were many learning moments along the way for me (you can see my primary headphone system by clicking on my ID). A couple things, although headphone systems are very personal.

Be really carefull of overly detailed electronics. The headphones are right in your ear… high frequency noice and distortion go right into them. If your system is fatiguing, even in a small way, this is your problem. Over time I moved to all tube headphone amps after too many fatiguing solid state amps. Many headphones need lots of power… I chose Woo for my amps… I have used three for thousands of hours.

Look for high quality natural sounding DAC and streamer. A PC can work… but at some point in improving sound a dedicated streamer is necessary to get really great sound. They are built from the ground up to be quiet and high fidelity. Yes, they matter. It may not be intuitive, but they can make a big difference with appropriate other components.

Headphones come in a multitude of sonic flavors. Some are warm, some are very detailed, some emphasize bass, midrange, or treble. What's your budget? What flavor do you prefer? If you don't provide more information all you're going to get is "This is what I have and like and it's what you should buy.", which to me isn't very helpful. 

Thank you audiogon friends for the suggestions so far. Several very good questions and points were brought up by yyzsantabarbara, gdhprentice and Big Greg.  I definitely do not want anything to bright, revealing or fatiguing.  A good balance is preferred concerning bass, midrange and treble.  Bass needs to be pronounced, controlled and tight without bloat.  Midrange needs to be full ranged and balanced.  Treble needs to be non-fatiguing yet fully balanced, not rolled off and without that digital harshness. In other words, fully there yet warm.  The full frenquency range is enjoyed in my case. The music I listen to is very dynamic.  An album can go from basic electric instruments with little to a lot of effects to the full arsenal of woodwinds, brass and strings either mixed with electric instruments or alone. Orchestral instruments can also employ a lot of electric effects at times. There is also a lot of digital affects in this music.  I realize a perfect setup is impossible yet as full of a reproduced range as possible is needed and liked. It's looking more and more like the Bryston needs to be scraped and a warmer solid-state amp, hybrid or just maybe a full on tubes solution is necessary with the correct headphones and cables to compliment.  My budget is in the 5000-dollar ballpark for a headphone amp, dac and headphones.  Looks like the Sennheisers are also to bright and high frequency attenuated for my tastes unless a full tube or hybrid solution would balance this out.  Maybe even a warmer solid-state amp. Closed back headphones are needed for noise reasons.  This basically raises the price and options are less.  Also, I won't have the open-air nature of open back headphones so I definitely don't want a bright system or headphone combo.  I'm going through a lot currently and would like to get a system up and running asap mostly to unwind at night.  I'm suffering serious injuries from being hit by a police officer with a ramming device and my mother and I were hit by a van a year to the day later made worse by an extreme lack of proper care, etc.  This includes neck and back injuries.  I'm looking for a good surgeon as this requires. There are and have been other problems making the injuries worse.  As a result sleep is rare.  Sorry so personal.  Music is healing.  Interconnects were also mentioned.  I do not want to go over 750 for interconnects yet realize how important they are.  With my injuries and taste a warm and comfortable setup is needed.  Also, I like the warm yet full frenquency side of the spectrum. Never had a tube setup yet grew up with analog/lps.  The warm and full sound produced by analog is missed.  It's much easier on the ears too.   A large CD collection will be in rotation with this system.  Thank you for your time and PATIENCE.       

Closed back, go with Focals as much as you care to spend.Same goes with Morrow cables. When you get a streamer make sure it has USB-A in to play your files, some do not.

Very sorry to hear about your injuries.

‘From your descriptions of the sound you like, see if you can find some Beyerdynamic T2 headphones to listen to. They among the most unique and natural sounding that I own / heard. While I listen to my Focal Utopia and Sennheiser 800s the most, because in absolute terms they simply out perform everything else. The Sennheiser are not trebly… in my system… they used to be in earlier incarnations of my system.

Also, consider not thinking about spending any money on interconnects… get the very best components you can. Then listen and enjoy… and at some point your finances can recover and then you can think about interconnects… as an upgrade and treat to really optimize your system.

Also, I am sure most folks found this true. It is really hard to do a one time purchase and done. It is hard not to learn so much from your initial repurchase that you want to trade or try different stuff to zero in on the sound you really want. But you have to start somewhere and the higher you shoot the less turnover you have.

I own or (owned) top level Denons, Sennheiser, Focal, UltaSonde Edition 8, LCD2, ADK, Grado… and some others. Grado can be relaxing. Denon (D9000) require massive power to get bass under control… then they are amazing.