About Sound Enhancer
Sound Enhancer is an Apple-developed digital sound processing technology introduced in iTunes 2 that adds additional life and richness to audio playback, improving the listening experience with headphones and with external speakers.
How to Adjust Sound Enhancer
Sound Enhancer is turned on by default. You can adjust the level of Sound Enhancer by following these steps:
1. Choose Preferences from the iTunes menu (Mac OS X) or Edit menu (Mac OS 9).
2. Click the Effects tab.
3. Slide the fader between low and high to adjust how much Sound Enhancer is applied to your music.
4. Click Sound Enhancer to deselecting the checkbox and turn Sound Enhancer off.