Since there are no dedicated Asus forums for other soundcards besides the Phoebus I feel obligated to post this here.

I have just gone from using onboard Realtek ALC1150 sound on a Maximus VI Hero motherboard with a set of Audio Technica ATH-ADG1 open ear headphones to a new Asus Essence STX II with the same headphones, and I am frankly finding the sound quality to be poorer than the onboard I was using before. Sound is generally flatter and lacks bass, and overall does not have the same kick.

Is anyone on these forums using the Essence STX II with a similar set of headphones (connections for headphones and built in mic are split into 3.5mm jacks) and I have plugged these directly into the rear of the cards headphone inputs and line in inputs with 6.3mm adaptors. The current drivers I am using are the only ones currently available from Asus, 8.1.11.5. Running Windows 8.1 64bit.

What sort of settings should I have enabled in the Essence audio centre software for a set of headphones? What sample rate and what level of gain? I am also not a fan of the way the Dolby Headphones 1,2, and 3 sound when enabled. I would prefer not to play around with any of the equalizer settings in the effects section of the software but I have found myself having to use the 'Bass' preset and then adjusting it from there to get anything sounding decent.

Maybe this all comes down the the current Op Amps in the card? Currently using the stock Muses Op Amps that came pre installed in the card. Can anyone suggest better op amps for headphone usage with this sound card?

Thanks in advance for any suggestions with this set up.