Denon AH-GC20 - Manual (Page 16)

Wearing the headphones
Adjust the slider to the preferred length.
.
R L
NOTE
0 Be careful not to trap your fingers, etc. in the moving parts.
0 Do not pull the slider too forcefully.
0 In order to hear the best quality sound, be sure that the ear pads correctly cover
both the left and right ears. If there are gaps between your ears and the
headphone ear pads, sound will leak and the bass level and effectiveness of the
noise cancelling function will be reduced.
Contents Preparation Connections Operation Troubleshooting Appendix
16