[mbkennel]

 
I just received a Audio GD NFB-12 from pacific valve.  I was hoping for an improvement over my existing audinst hud-mx1, being full size & seriously powered.
 
Well, physically it looks great, solid with a nice headphone amp.  The problem is that 44/16 music (which is 99% of mine and I use Pandora etc where I can't insert a resampler) doesn't sound good.  I read things about "tubelike", but it is really quite plump and unclear. (My music is 100% classical).
 
At 96/24 it was quite a bit better, but honestly I preferred the Audinst at straight 44/16 over everything. It had the right balance and actual deep bass.  Of course it is broken in and the audiogd probably isn't yet.   But the portable audinst with a cheapo switching power supply well beat the heavy desktop from a serious designer.
 
Three is only a 30 day window to return to pacific valve.  What else can I get at up to near $300.  I am interested in USB only and want a headphone amp and DAC with RCA out.
 
 
My headphones are HD580 and Denon D5000.  I was planning on comparing the audinst and audiogd and selecting which I wanted to use at home mostly with speakers (magnepan 3.6r) and which at work with headphones.
 
I've read that the audio gd nfb-12 is 'tuned' to be tubelike, and I guess I don't like this tuning.
 
My precise question:  which should I do?
 
a) return AudioGD 12 to Pacific Valve and get Sparrow (probably cheaper B model)---does it have a different sound signature than the -12? @ 44/16
b) return AudioGD 12 for refund, eat the "restocking fee" and buy another Audinst?
c) try something else?