[Darkimmortal]

I've read some posters claiming their 250-300 ohm headphones cannot be driven anywhere near 'maximum' volume by the D1/DX series of soundcards, and yet for me 30% windows volume is painfully loud (volume not quality) and 10% is about normal.
 
On my Galaxy S phone with Voodoo Sound, which has a 300 ohm output and exceptional DAC quality I notice almost no difference, but going into the volume levels I can't listen to without pulling the headphones away from my head there is audibly less distortion.
 
Playing back bassy sine waves etc. I surprisingly get more out of the Xonar, and I am under the impression that bass is where an amp makes the most difference besides clipping/distortion?
 
Would I be correct in assuming I am getting the most out of my DT150's without buying a new amp/dac for my PC?

 

[stv014]

The Xonar DX has 100 Ohm output impedance, which, due to the reduced electrical damping, likely increases the bass quantity and bass distortion somewhat (not by much, though, if the drivers in the DT150 are similar to the 250 Ohm DT770 and DT880). Other than that, if you can easily get loud enough volume - something that is quite different for everyone - with headroom left, it should be OK.