help needed for new headphone system

Lots of great suggestions here. 

I've been wanting to try a tubed headphone amp (most likely Woo), but haven't experienced one, and hesitate to make recommendations for products I have no experience with. 

Your HD650s are really nice and will benefit from a better cable and a good headphone amp.  I have a pair of HD6xx, which are basically the same and replaced the stock cable with a balanced cable and use them with a Sony TA-ZH1ES amp.  I have a dozen headphones including some TOTL cans like Audeze LCD-4, but find myself going back to the HD6xx for their comfort and how easy they are to listen to. 

I have also replaced the stock earpads on most of my headphones.  This doesn't typically result in a big sonic difference, but almost always increases comfort.  

For higher end headphones, the Sony MDR-Z1R are a great value.  Excellent sound quality, deep bass, while being light and comfortable.  

Note that I tend to focus on comfort as much or more than sound quality.  The LCD-4 sound amazing, but they are heavy and not the most comfortable thing to have on your head for a long period of time.

Many thanks for these posts.  This information will make my search much easier.  I was unaware of ZMF, and they are only 10 miles from me!  

https://danclarkaudio.com

Highly recommend looking into this brand. The Noire x line closed back $999 open back $1299. This is his mid tier line that start using his patented AMTS technology.

That will leave you plenty in your budget for amplification, I suggest something with low output impedance.

Hey OP

First off, I am not a headphone guy, but I do have Ls3/5A speakers for my reference system. So, at the last Audio Show, I got curious and listened to some headphones at the Show. Well, I was impressed. I always compare what I hear against my reference gear. I believe that some good implementation of Headphones could be very good sounding and satisfying overall. 

The choices that perk my interest BASED on how it sounded and close to my main gear was presented by a Pathos headphone amps and T+A headphones. (forgot the model). Another one to consider is Felix amps and Audeze headphones. I do own a headphone gear (just the headphone) and it's an electrostatic HiFiman model but as I said, I'm not a headphone guy.

Ultimately, you need to go visit an audio show or a favorite audio store to check out before making the purchase. my post merely recommends brands that I heard that are close to the speed and tone of my Ls3/5a and ATC speakers. 

just my 02cents

@joeycastillo I'm in the same boat.  In addition to the LS3/6 set I have a pair of Spendor LS3/5R2, and it is that wonderful midrange that I am looking to find in a headphone setup.  I should have been more explicit in the original post.  I will look at the Pathos and Felix amps, and the T&A cans.

I go to Axpona every year and will go next April, but I don't seem to get much out of listening to cans in that big, busy, noisy hall.  Just me.  I may take advantage of the generous TMR return policy (5% restocking fee) and try a few items they have available.  Thanks for the comments.