Amp for desktop system?


I'm in process of building a new desktop system for my home office and need to choose a standalone amp (not integrated) for whatever speakers I purchase. Any input would be much appreciated - I'm getting lost digging through the forum archives!

Details: Nearfield listening while at the computer (3 ft), small room, up against a wall/window, lower volume levels so the "first watt" principle matters a lot.

System will be PC Apple lossless iTunes -> External DAC/Pre combo(Beresford 7520) -> Amp(TBD) -> Speakers (TBD - Likely Totem Dreamcatchers/Mites, Epos M5, or Usher S-520). Music is all over the board, alternative, jazz, female vocalists, eclectic misc stuff.

Sonic preferences - I really value a spacious, airy sound with fluid vocals. Soundstaging is a priority (contrary to my layout, I know) and an open detailed sound is more important than pure dynamics, probably won't get played loud much. Tight accurate bass is more important than a deep low end or slam, esp with my small speaker choices.

Budget is $250-450, used gear here on audiogon is the likely source.

Any suggestions on what brands/models to consider? I get totally lost looking through the classififeds.

Am I on the right track with the rest of the components? Still trying to decide on the speakers but am leaning toward the Totem Dreamcatchers (4 ohm speakers) after demoing them yesterday.

Any help is much appreciated. Thanks!
sheldonn
I agree with Lapierre, most of the monitors are meant to be on a stand, not sitting on a desk.
I'd almost suggest a pair of Realistic Lineaum's for speakers. The open dipole tweeters will keep the sound from being right in your face. Much softer soundfield.
Also, assuming that this will be on all of the time, tubes are out & class A will be like having heater on your desk. Those are usually the warmest first watt choices.

Have you checked out the "T Amp"? Tiny & smooth...

Last suggestion that I've spent a lot of time with is the new Boston Acoustics Horizon radios. Way better than Bose Waves and less money too.
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Hi Sheldonn.

You might consider active (self-powered) speakers. The Audioengine desktops are recommended by Stereophile magazine.

http://www.audioengineusa.com/tech_stuff_a5.php

Mike
Thanks for the suggestions everyone. Bob, I'll have to read up on ATI amps - that looks very interesting!

I suppose I should have clarified earlier... I'm currently running a setup with the Audioengine 2's. They sound good, but I'm looking for a little bit more. The current setup is:

PC Apple lossless iTunes -> Beresford 7520 USB DAC -> Kimber Cables -> Audioengine 2's

It sounds good, but I'm looking for a little more out of the system. I recently found out that I'm going to be working from home full time starting in a month or two, and I'll be able to listen to music a LOT more than I can in my current office environment.

I figure I might as well get something that I'll really be able to enjoy. My downstairs system sounds great (Mac Mini/DacMagic/Rotel/Kimber/Thiel) but I'll be locked upstairs in my office 8 hours a day!