affordable DAC for rock/metal

Yeah, I have to agree about the Valab. When I was comparing a Valab to some other dacs (Dacmagic being one of them), the one thing I really liked about the Valab was it's ability to allow me to totally crank up my nastiest sounding rock/metal cd's, and they remained listenable and enjoyable, even with my Magnepans. I ended up settling on a Jolida player, but I hung onto the Valab and I'm considering throwing it back into the rig, and use it on occasion as a "party" dac :-)

Are there some DACs that sound better for Jazz, Classical, books on "tape," or Folk?

Isn't the most accurate always the best?

Newbrook. Yes, most accurate is usually best overall, but not all CD's are recorded/mixed the same, and many rock/metal CD's can sound overly aggressive and annoying on many high resolution systems. Some players and dacs are known to sound more "forgiving", and the Valab is one of them. Far from the bottom line in detail, soundstage, air and recorded space, but it can be very "listenable", as far as "just enjoying some music".

Ideally, your system should sound good with all types of music, from acoustic to amplified, but that's not always the case. Throw in the fact that some CD mixes sound terrible, regardless of music type, and things get even more inconsistent. Everyone has to "balance" their systems for what works best for them, and there doesn't seem to be a "one size fits all" system, at least in my budget.

"many rock/metal CD's can sound overly aggressive and annoying on many high resolution systems"

Not sure I'd agree with this.

A good high res system only gives you what is there. Rock/metal can be a lot more difficult for a system to reproduce well than many think. You have to have good overall system synergy and component matching and amplification that is up to the task of reproducing dynamics and transients effortlessly, otherwise things become nasty, fatiguing and annoying.

Don't know if it's within your range or not, but this is certainly a stellar review of the Bryson DAC:

http://stereophile.com/digitalprocessors/bryston_bda-1_da_converter/