May 2014 - last edited February 2021
Mass Effect lacks surround sound on most hardware, and even if your hardware is supported, it requires tweaking a file to implement it. When applying this tweak, you get the following:
Note that this is only supported on a minority of sound cards. Supported hardware includes some cards in the Creative X-fi and Asus Xonar lineups. It may also work on onboard audio solutions on ASRock and Asus motherboards if you install X-Fi MB, which is premium software.
MaxChannels=128
TimeBetweenHWUpdates=15.000000
MinOggVorbisDurationGame=20
MinOggVorbisDurationEditor=4
TotalAvailableChannels=128
DeviceName=
UseEffectsProcessing=True
ReserveChannels=2
Don't change any settings in-game, because it may override your ini file. If your hardware is supported, you will have 5.1 surround sound, possibly with environmental audio as well.
Creative Alchemy is NOT required.