Zd542- yes I am aware of the NAD M12, thanks for input anyhow. This preamp would be perfect of my needs (other than the fact it's manufactured in China) but unfortunately its way out of my price range (which is $1,500-$2k). I will most likely have to look in the pro audio market.
Regarding the obsolete question- perhaps obsolete is was not an appropriate term. I should have said out dated enough that in comparison, something new would sound drastically better. I see what you're saying by not judging by specs, however, specs are useful tools to give an idea where something stands. For instance, an old tube receiver from the 60s may have higher distortion than a new amp and it is safe to say that one will hear the difference. The same can be said about SACD/Blu Ray vs. Redbook.
I need to read up on the subject of digital amplification, I suppose. Looking for sampling rates would be one example of a spec that is pertinent. However, its true-if it still sound good, it's not obsolete. The Air20s sound great. Just wondering how long it will be before something drastically better comes along. Digital seems to be evolving much faster than analog these days.
Mapman- thanks for your input.
