for 2500 i would get a hegel h120 (list is 3000, available from retailers at 2500 or close to it)
superb sound and power, excellent build
the hegel h160 mentioned by @soix is an excellent amp, but the dac is a bit old now, newer hegels have a cleaner more dimensional dac section
you will need a phono stage though, as hegels do not have one built in
for less money, slightly less pure sound, but very nice build and form factor, i second @soix suggestion of a nuprime ida-8
the above are superior to nad, cambridge and arcam imo, you will hear the difference on your spec 40s