[CanIHasThisName]

I've been using the Ultrasone HFI-2400 for a while now. Instantly fell in love with their build and of course, their sound (which was only getting better as I was burning them in). And now, after a few months, I definitely decided to keep them.
 
So as the title goes: Has anybody got any solid recommendation for a DAC+AMP solution?
 
Been using them with FiiO E17. Use them for absolutely everything (= games, movies, music, sitting at the table while nothing is playing and I'm wondering why I'm still wearing headphones)

 
The sound isn't bad at all, but the thing is - I gotta have the gain set to +6dB. And when I want to have the volume at "oversatisfyingly high levels" for short listening sessions, I need to crank up the volume all the way to 50 and more, at which point silent hiss is noticeable. It's quiet, but it's there, so the E17 has to go, at least as far as amplifier goes. Right after I get a new monitor, I intend to buy a proper amplifier.
 
Since I own FiiOE17, FiiO E9 became an immediate candidate, for obvious reasons. I am a PC user, so I require DAC capability. And since I intend to buy a PS4 in a distant future for exclusives, optical input is a MASSIVE advantage for me.
The thing is, HFI-2400 has it's highs a little bit too high. This wouldn't bother me, but in some cases, high sounds can get upright unpleasant ("s" of some female vocals and so on). So I've been thinking of maybe getting something with a more appropriate signature for these headphones.
 
Thanks in advance for any advice.

 

[cel4145]

Budget?

Also, HFI-200 sensitivity is 94db into 70 ohms. So if you are looking for significantly more volume, I would definitely suggest looking at desktop headphone amps.

You could use the line out on the E17 with the FiiO E7 to use just the DAC in the E17 and hook up any external headphone amp.

Since you say you are getting new speakers, makes sense to me to get a headphone amp with a pre-amp so you can hook your speakers up as well and control the volume with the same volume knob.

 

[CanIHasThisName]

By monitor I meant a screen I'll be a getting a new screen, not speakers.
Budget is pretty loose and I'd "generally like to stay around the price of the headphones".  Would like something in between 200-300$ but if 400$ would be worth it, yeah, I'd dish that out. 
Significantly more volume is not necessarily what I'm looking for. The FiiO E17 can produce satisfying levels of volume but unfortunately, it produces noticeable hissing noise at these volumes. It's quiet, but still.
As I said, FiiO E9 is a candidate (because it can be used with E17 docked in it and will leave me with an equalizer and optical in), but since I understand that it's sound signature is similar to that of E17, I was thinking that maybe I should get something that would fit the headphones better, since their highs a little rolled off.

 

[cel4145]

By monitor I meant a screen I'll be a getting a new screen, not speakers.

LOL. I was definitely reading the forum too late last night.

Not sure what improves upon the hissing of the E17. It has been awhile since I owned it, and I don't remember it having that problem with any of the headphones I used it with. However, ClieOS did remark that there was minor hissing at very high volumes in his review. In comparison in that shootout, he described the Objective 2 as dead silent. Perhaps the ODAC and O2 amp would be a good choice for you.