Is there a Music Player for this?

I'm looking for a quality music player without a built-in DAC or hard drive for the music files. So, a hard drive for just the operating system is fine. I want to store my music files on an external hard drive using either an eSATA or Firewire connection to the music server. And, I want to use either a coaxial, optical, BNC, or AES connection between my DAC and music server. I also need to use my iPad as the controller.
Sounds like you are describing the Bryston digital players, BDP-1 ($2200) and BDP-2 ($3000).
Getting the best result from this requires that you use USB, not S/PDIF, and force the Master Clock outside the server in a USB converter. There are at least 2 servers that output music streams over USB, Antipodes and Sonore.

A good USB converter is the Off-Ramp 5 with Dynamo power supply. Avg jitter in the 30psec range.

Steve N.
Empirical Audio
Thanks guys! I'll check out these products.

Okay, the Bryston BDP-2 reminds me of Chris Connaker's C.A.P.S. (Computer Audiophile) player. It adds the eSATA option for the external hard drive which I want and upgrades the OS from Linux to Atom. Chris' new version upgrades his C.A.P.S. to Windows 8.

If you have a Firewire DAC (I don't), you can add it to the player. My problem, is that I prefer the sound of my coaxial connection over my USB one in my current setup.

Steve, are you saying that the USB converter makes the difference when using USB, and so then preferable over S/PDIF?

I need to make a correction. I meant to say that I prefer the sound of my coaxial connection in my current setup, over a USB one that I previously tried (different player). So, really apples and oranges.

Steve, I read a Six Moons recommendation of your Off-Ramp 5, so now I get it.

Kenney - Off-Ramp 5 has gotten even better now by adding 2 accessories:

1) Dynamo power supply (linear based on Hynes technology)
2) BNC-BNC coax cable with RCA adapters - unbeaten so far

Where did you read the 6-moons recommendation?

Steve N.
Empirical Audio
It was an indirect recommendation as the result of rave reviews from forum chatter, mentioned during Six Moons' review of the Synchro-Mesh.
Steve, do think that a player with a USB output like the antipodes would sound better running into the DAC via an Off Ramp or run directly into the USB input of the DAC through a good cable?

I'm very interested in the Antipodes and thought it sounded good with USB input to my DAC.
I'm using a Sound Science Music Vault Diamond player coupled to my Weiss Dac 202. I currently use the AES/EBU connection to the Dac but this unit will do Firewire or USB also. In my system, it beat the pants off the MacMini I previously used.
I have changed my mind on the configuration, and I will use my NAS for file storage/playback.

The Music Vault looks like a winner, however.