I've searched through several threads, tutorials and websites but haven't found anything about how to do the geiger counter effect in Half-life (1).
I've tried doing this effect myself but I haven't found a way to do this yet. Using an ambient_generic playing the geiger counter sounds will cause them to have the same frequency as you travel closer/further from it but the volume will fade instead of decreasing/increasing the frequency as it should do.
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Then I just ask you guys, how to do this effect?