I work for German Physiks and can provide a little information that may help you. The biggest difference between the German Physiks Carbon Mk IV and the Duevel Sirius is that the DDD driver we use has a very wide operating bandwidth. In the Carbon it covers 190Hz to 24kHz. Consequently there is no crossover point any where near the midrange, which is where our hearing is most sensitive. You can find out more about this on our web site at http://bit.ly/UPdMPZ.
I cannot comment on sound differences and as I work for German Physiks, I dont think it would be professional of me to do so. I talk to a lot of people around the world in my job and as Duevel are a competitor, their name comes up from time to time. I have only ever heard good things about them, but they are German like us ☺
If you will be attending the Axpona show in Chicago next April we will have a set of Carbons there and I would hope that Duevel would also be there, so you should be able to hear and judge for yourself.
