New O2 amp, how to connect to sound card?

[NukeDukem]

Hello, I just received the O2 headphone amp to drive my AKG Q701s. The O2 uses a 3.5mm input.

My question is, whats the best way to connect my X fi sound card to the amp? Should I use the 3.5mm headphone jack -> 3.5mm O2 jack? Or should I buy a RCA -> 3.5mm converter cable and use the RCA outs on the sound card?

I'm not sure if there is a difference, but if there is I'd like to know, thanks!

 

[ultra]

Just use a 3.5mm headphone jack, male to male and plug it in.

 

[Impulse]

RCA out on the THD is the line out and 3.5mm is the headphone jack no? I think you should use the line out, grab an RCA to 3.5mm cable or adapter.