

At the very least put the onboard analog output through a good headamp or even better, take the digital out to a DAC, or use a separate, good quality, USB connected DAC. The greater improvement in audio with those cans, which have great soundstage and treble definition, is not using motherboard onboard analog audio to drive them. If you know you have a different source rate of 48Hz, do change it to 48Hz if you deem it worth the bother for those rare occasions then switch it back to 44.1Hz again for most uses.

However that's probably not what that windows setting means, rather it means if you don't leave it at 44.1Hz, it will resample in order to get to 48Hz which is a loss of definition because the standard source rate is 44.1Hz. The output sample frequency is better higher than 44.1Hz but if dealing with lossy compressed sources, and analog motherboard output, you may not hear a difference. It's not the OS or cans that determine your audio options but rather the audio chip and driver support. If you want special effects, it might help in some things like games but overall probably not desirable in video/audio but some like that too. Most purists would say leave the settings at their defaults, leave the audio as the creator intended. I've owned some of the Sennheiser 5xx line, like them but it comes down to your subjective preference and there are other things better to do.
