Basics4Mac - Understanding System Volume Vs Application Volume

Seemingly conflicting controls

System volume and application volume sliders
Click to see a larger image

Mac OS X has a a System-wide volume control and many applications such as iTunes, QuickTime and Safari videos like YouTube have their own volume controls. To get the proper volume level you are looking for, it is important to know how system volume and application volume interact.

The system volume setting is controlled by the F11 and F12 volume keys on the keyboard. (F4 and F5 on older keyboards) When you hit these keys a bezel pops up on the screen that shows the current volume level that changes as you hit the volume up and down keys.

In the screen shot above, you can see that the system volume is set at about half volume.

Applications or web pages that play sound have some sort of volume slider that you change with the mouse. In the screen shot above you can see that iTunes is set at full volume.

The system volume controls the over-all volume for all applications. So in the case of the iTunes screenshot above, with the system volume at half, the iTunes volume slider will actually change the music volume from 0 to 50% only.

This can be confusing when you are playing music or watching a video and it seems like you can't get the volume loud enough, even with the application's volume slider all the way up.

For convenience, I normally keep the application volume controls set at 100% and then adjust the volume from the keyboard keys.