Creative SB1500 User Manual page 7

The Volume Control knob on the ACM controls the volume output to your headphones, giving you quick
control over the audio level from your games or music.
Note:
The ACM Volume Control Knob allows you to adjust headphone levels conveniently based on the
maximum level set by your computer's master volume control. We recommend that you determine
the desired maximum volume on your computer before using the ACM.
About Your Hardware 6