This is my latest system.(again!) It plays all types of music with equal enthusiasm. I've just upgraded the preamp with the KSL Silver M7. SWEEEET!!! Well, I've sold the horns and now am using the full range Sonatines with Phy drivers. Really special!!
Drubin-- I'm an "Audio Note" guy... and I have to say that yes, Audio Note equipment can sound wonderful in systems that are not comprised of all-AN gear.
Amp and speakers are most important. In my opinion, you should get the very best speakers you can first. If you don't have fine speakers, you will never experience what the rest of your system can do and, thus, will not have ever truly 'heard' the rest of your gear. (This comment is not brand-specific.)
Next, it is important to have an amplifier that mates quite well with your speakers.
Only then, in my opinion, should you worry about the components upstream. it may very well be that you like how they sound.
If you go the other way (DAC first), you won't experience it's true magic/you won't realize everything it can offer. Rather than attempt to swap many components at once, put all your money into speakers you will keep for a long time. Then, as money permits, invest in a second piece that will also keep for the long-haul.