[L. Duke]

It should be just the path after the sound part. I did hear from one person that to use the old sound they had to hl2/sound/ at the front of the path to get the old sound.

When I tested it on Windows and Linux, it worked fine with the one shown, but you could try both methods.

Also, you'll have to change maps before the sound works because it has to precache the sound when the map loads.