Need audio help

i could not find it in the specs, but it looks like both optical or 3.5mm inputs are available on the 840. it might also have usb as well as a standalone option but you would need to read the manual. i think the usb might be just for microphone.

honestly, optical is not needed given how i believe that set uses dolby virtual surround sound to emulate true surround sound so going with optical is only beneficial if A) you have a bad dac onboard your pc or B) dont have a decently shielded 3.5mm cable.

the z906 can use optical for 5.1, but optical only can carry an uncompressed 2.0 signal. when it is used for 5.1 (and all devices would need to support it) it would be a compressed audio dolby digital signal. going with analog 3.5mm cables may actually sound a little better depending on the quality of the source you are connecting up. optical would only sound better if the dac onboard the z906 is better than your onboard or if you have alot of EMI where going with analog might be affected.

there are such things as optical switches, but given how one source would be 5.1 and the other 2.0 it would not be so hot swappable without changing all your settings. going with one analog and the other optical or going with both as analog would be better.

if you have both plugged in at once, you can swap between them using windows default audio device instead of unplugging one or the other. it is also possible to just plug in your 840's headphone (3.5mm) cable into the side of the z906 pod when you want to use it.