Pink Floyd and Weed

Hi,
My main system Amp has no pre-outs or tape loop, but I think it's possible to convert one of it's single ended inputs to something called pass-through for HT use, whatever that means?? Right now my streamer has two outputs, one balanced going directly to my main amp and the other, single ended, going directly to my headphone amp. I am very interested in the Quick Silver headphone amp but I noticed it does not have a pass-through output which I need for my PC speakers. I guess I need to research my Amp to see how to configure one of it's inputs to pass-through, that would fix my issue and make the Quick Silver viable.

Are you a Roon user?  If so, go to the DSP settings, switch on the cross feed, then adjust the profile so you hear things how you like them, and save the settings for these headphones. 

I currently do not have Roon. I have heard quite a bit about Roon, but never researched it and am not sure what it is/does? I do play back my hi-res download files from my PC using an app called J-River Media Center. Right now I have J-River configured as pass-through, making zero changes to the digital file's. My Streamer is Roon Ready, not sure what that means either?

What is Roon and what is Roon Ready, anyone?

Room’s own website is excellent - Roon is not like any other service so it is a must read. 
But basically, you install software on a powerful processor (like your home PC or Mac). You then install Roon apps on your phone or tablet which you will have with you in your listening room, to control the music. 
Then you connect suitable streamers wherever you want music; as many as you like - I use a Bluesound Node, a R-Pi, a Chromecast, other Macs. If you want you can also connect a DAC directly to your main processor. 
Roon finds each streamer/DAC and can send different music or the same music to any combination of them. Each end point can have a custom profile of DSP and other filters. So for example if you only use headphones with your Chromecast you can build in a DSP profile for that combination. 
You hook up Roon to your NAS, to Dropbox, to your music folders on your main processor, and to Qobuz/Tidal.  Roon finds, sorts, and describes what you have got, dragging in information about the music it finds and showing it to you on your controller devices as you listen. It’s like having the best LP covers of all time, for all LPs, instantly. 
Best of all is the audio metadata. Roon tells you loads about your signal path quality. It is a digital fiddler’s dream.  

@grm  First are we talking problems with Division Bell or everything through the headphones?  Accepting that this is a general problem not DB specific, do you have any way beside USB to get out from your computer?  I live in Canada so I am too busy rolling to spend much time swapping from USB to co-ax or toslink to compare sound.  I use something completely different to get hi-def and vinyl transfers from my PC to the stereo so I never bother with it but I have seem many posts commenting on differences between the various methods and USB didn't seem to be very popular.  Great for compressed or low def formats but the better the audio signal the bigger the differences according to most who commented.

As for the other issue, have you watched the Gilmour in Pompeii blu-ray?  Great show and if you take the same break the the band takes between sets ;) the startup to the second set will blow you away, crank it!