Pros: Affordable , Upgradable, makes all digital sources sound cleaner bigger and better.
Cons: None , as a first unit it destroys onboard soundcard in my mac, pc and ipod
Could not be happier with the D1 .(Bought with Opa 627 upgrade and the ge5670w tube.)$264 delivered.
It has done as advertised and upgraded my digital music and movie collection in leaps and bounds.
As this is my first unit i can not make any comparisons.
My beyer Dt770 pro 250s now sound so much fatter that they have a dac/amp driving them.
Using Media monkey on pc laptop playing 44.1 mp3's via usb into the D1 with the beyers and everything from Reggae to blues , Hardcore metal/punk to dubstep just sounds awesome,
huge improvement on standard soundcards highly recomended!
Using the tube preamp through my old logitech 5.1 speakers adds warmth and depth and a truckload more volume, turning the volume up full on D1, and to about 80% vol on the logitech with no distortion!!! just a big fat sound that annoys my neighbours and gets the wife all sexy and fired up , lol.
Plugged into the ol yamaha Htr 5630 av receiver and similar outcome to the logitechs ,
movies are sounding awesome straight from the pc using hdmi into the tv all while the D1 is still connected via usb then tube pre amp out into the Yamaha.
All in all this is a truly versatile unit that has totally impressed my wife and friends.
It is so awesome for the money and has made all my old speakers and new cans sound like i don't need to fork out for upgrades for a long while !!!
Although more cans will be coming soon i think! mmmm sweet sweet cans.
It is a great start and has inspired me to explore the Audiophile world .
I now have a new found love for my music collection,
thanks to everyone for their great reviews, especially spanky .
Do not have any regrets buying the D1 , it does it all , without eating a hole in the pockets!