Preamps (at least preamps in same price range) are generally not "better" than one another...just different. Think flavors. Colors.
The DMP-3 is pretty clean, and full. It's not gonna mess up your sound. It's pretty honest. I used it for acoustic guitar this afternoon and it did just fine. It actually surpised me with it's low end. I usually use it for drum overheads and room mics.
I have and use ART MP's for lots of things. For a box with only 2 knobs it's amazingly hard to use properly. lol. Finding the sweet spot takes fiddling.
I haven't used the DMP3. I used to have a DMP2 and the experience has made me stay away from m-audio completely.
I have both of these. I've since moved on to Sytek's and Grace's. The DMP-3 was great UNLESS you push it at its upper limits and then without warning it breaks up in a really, really, nasty way. Did I say really? I meant really.
The Art is hardwired these days for bass DI. Gorgeous tubey warmth and fullness for this application. Did I ever plug a mic into it? I must've...
even tho' i do my own diy pre's i was curious about the tube mp.
before i got one. i had heard so many conflicting reports.
some folks say its total garbage then i heard some clips someone posted and went wow ! so i thought what the hey....get one and try it.
heres a little song still in pre production/bed tracks stage where the rough lead vocs used the tube mp. www.motagator.com/bmanning page down to the build a man up song.
note....unlike many on here i cant afford uber duper ADA convertors. ......
due to other family commitments...just in case anyone wants to get super critical.
a tip for you if you get a mp.
google for tips on changeing the tubes in them. i'm useing stock.
what ive found with this unit is to not push the output control too high (or input)....and take output into a likkle line mixer for any added gain or say a comp/lim before sending to sound card inputs.
maybe someone can confirm..it seems a new mp version is out i was told.