Help setting up Computer audio rig

[quikgp]

Brief description, I have 2 separate systems that I listen to music on, one stand-alone 2 ch audio system and a computer system. I've found that I haven't touched the 2 channel system in over a year, because I'm always at my computer when I'm listening to music. Also, the house I live in is very open concept, so when I use my 2channel speaker setup, it bothers my wife who might be downstairs working or watching TV.

So basically, I'm looking to switch/sell off my 2 channel setup and upgrade my computer's sound.


My 2 channel system is as follows:
sources: Rega P3 turntable and Rega Planet CD player
Intergrated Amp: Rega Brio 3
headphone amp: Gilmore Lite
Speakers: Focal Chorus 807v Bookshelf
interconnects: Atlas equator MKII RCA cables and Atlas hyper speaker cables
Headphones: Denon D2000

Here is a photo of my 2 channel setup:

My computer setup:
source: FLAC audio files currently going out of 3.5mm jack with onboard sound
Speakers: audioengine B5a (not the plus version, so I dont have RCA input jacks)
Headphones: Grado SR60 powered out of headphone output on computer case

Here is a photo of my computer setup

I'm looking for suggestions for a DAC preferably one with a headphone output that will be similar quality to the Gilmore lite. I love my Denon's but I'm also thinking about getting a pair of HD650's, so the amp/dac doesnt have to be specific to powering the Denon's. I've seen adds for the yulong D100 and Matrix quattro, which look good, but I'm not sure if they're above/below the level of the gilmore lite?

Is it better to use a USB to send sound to a DAC or should I be looking at optical or spdif? Do I need a sound card for that?

Also looking for suggestions of speaker placement on my desk - would it help if I had small stands or foam blocks? should I toe them in?

Thanks in advance

 

[PurpleAngel]

Asus Xonar DX (PCI-E) or D1 (PCI) sound card (CS4398 DAC chip)
Comes with Dolby Headphone surround sound, for those times when your not listening to music.
DX/D1 sell between $65-$82
 
O2 (Objective 2) portable headphone amplifier, $155, also works just like a normal AC powered desktop headphone amplifier.
Can drive headphones from 16-Ohms up to 600-Ohm
It should improve the audio quality of the Denon AH-D2000 (25-Ohms), compared to plugging the D2000 straight into the motherboard's headphone jack.
The Senn HD650s are 300-Ohms

 

[quikgp]

Does an internal sound card provide equivalent audio quality to an external dac?

 

[PurpleAngel]

Quote:

Does an internal sound card provide equivalent audio quality to an external DAC?

I'm somewhat biased for internal sound cards over external DACs, because you get surround sound for movies and gaming.
A sound card is one less thing taking up desktop space.
 
Audio Quality, depends, if your computer suffers from electrical noise inside the computer case, it can affect the (post DAC) analog audio signal on the sound card.
An external DAC would not be effected by "noise" inside the computer case.
 
I think most people with internal sound cards do not has a noticeable noise problem.