have you heard a naim headline? it would make for an interesting comparison.
Yes, I've heard the Headline 2 with the NAPSC. Listened to it critically twice - for over an hour each time at the shop.
Not sure I can give you a useful comparison for these reasons:-
1. The environment wasn't ideal. The shop wasn't exactly the quietest place to pick up subtle variations;
2. Tested it with the shop's K701, SR325i and HD650 but not with the RS1;
3. The CDP and cables were different from mine.
But, FWIW, I'll give you my impressions anyway. What grabbed me immediately was the bass - the Headline 2 that I tried was a bass monster. It had the weightiest bass of any amp I've heard. With the Naim, the K701 sounded the best all-round, the SR325i was sublime for rock, and the HD650 was unbearable. For some reason or other, the mid-bass from that HD650 through that amp was treacle thick, slow and heavy - I removed the HD650 from my head after just 10 minutes.
A number of consequences followed:-
1. I bought the K702 (because it was a new model and I could always change the cable myself without sending it half-way round the world to have it modded);
2. I bought the RS1 (well, I reasoned then that if I liked the 325i, might as well go all the way and get its big brother); and
3. The HD650 is yet to be in my stable of cans. Before I get flamed, I must say that I do want to audition it again (preferably on my set-up), but that opportunity has yet to come by.
That Headline 2 had the PRaT of the SRG - it was toe-tappingly (couldn't head-bang in the shop) enjoyable. Headstage was narrower than the SRG's, but separation and clarity were excellent. I also seem to recall it being a little colder than the SRG. But the bass, oh the bass...
I thought at first that it could be the CDP that gave the Naim THAT bass. Looking at the review below however, it would seem that that particular CDP was not particularly bass heavy.
6moons audio reviews: C.E.C. TL51XR
Well, there you go. YMMV