Pink Floyd and Weed

@grm Are you hearing weakened bass through the headphones on other sources or just the streamer.  If it's everywhere is there a chance the headphones are wired out of phase?  
Just as an experiment, use the equalizer in J-River to wind up the lowest two faders.  If you get the expected bump in bass energy see if there is a boost setting that makes the phones sound more like you want.  Also run the faders to the bottom to see the effect.  Try the same thing with your speakers, of course watch your levels, massive boost at low levels can be dangerous.  Also check out the analyzer in J-Rivers DSP section.  The graph will give you a decent view of the music you are sending out.  It's great fun to watch if you are a music lover who is also a tech head.  After you get used to looking at it you can easily see if a track should sound bottom heavy, balanced or bright.  Being able to see the "tone profile" of a track makes it easy to determine what the overall sonic character of the song is.  Before I get jumped, no it's not a high precision evaluation technique but it does help.

russashe,
The HD600's are wired correctly, the connectors on them are keyed in a way, one large and one small pin on each connector, you would have to use quite a bit of force to wire them out of phase.
I have fumbled a bit with J-River and am concerned I'll mess things up if I am not careful. I am using Media Center 23. It sounds like you have a more in-depth understanding of J-River. Any way you could share something like a fault tree that can get me to these settings? Anyone out there with J-River that might be able to help? Thanks!

@grm  No worries glad to help but you still haven't said, is bass light on everything or just the Floyd.  Anyway, J-River is dead easy. Pick TOOLS from the menu bar, bottom choice OPTIONS.In the main box you have a list, the first choice is Audio Device, second is Settings.  Usually the only choice under Settings is "DSP & output format", choose that. In the new box along the left side is a list of functions ; equalizer, room correction lots of fun tools.  The last one is the Analyzer, select it with a track playing and you see a graph of the sound level/freq.  Don't worry about messing settings up it's a computer app.  If you get way out of whack chose the default preset.  Also you are usually asked if you want to save changes before exit.  The analyzer is just for fun but is very interesting in what it displays. For simple checks involving boosts and cuts just to see what happens the plain old equalizer is the place to start.

russashe,
The bass through my HD600's is light on everything. Through my main speakers everything is fine and it's not just the Floyd recording.

I have printed out your navigation instructions for J-River, I really like the app and what it can do. I'll be trying your suggestions with it right after this post, many thanks!

Hi,
Adjusting the equalizer in J-River did the trick, many thanks! At some point I think I would like to invest in a new headphone amp, with the Quicksilver high on my list.

Happy listening!