Preamp

Would recommend the Reference 5se which is definitely quite a step up in performance than both the GSpre (take a look at the interior of both units and you will see the Ref 5se has much more capacitors and beefier power supply) and the Mcintosh C2500.   If you could afford, go for the Reference 6 which is on a whole new level of performance...fast and palpable, even more transparency, more 3D holographic imaging, more deep tight controlled bass.  I would not imagine any other tube preamp under $20K could even compare to the Ref 6.  Especially when running with the Pass Labs amp, the Audio Research will be a match of heaven!  

I cannot afford the REF 6 unless I could find one for $7500 and in would have to sell my Rel R528 to do that. You say the C2500 is also a step down from the REF 5 SE?

dskinner5, 

C2500 is a nice pre but not in same league as 5SE. In fact, ARC LS28 bettered the C2500 in my system. 

I agree with audioguy recommendation of 5SE if you can’t afford Ref6. But if you can swing the Ref6, you will be set for a good while. 

I am saving up my pennies for Ref6 :-)