After a bit of experiment using Layer Styles, I come up with this speaker icon. I hope you enjoy it.

[hr]
[ilink style="download" url="http://psdfreemium.com/download/884/"]Download PSD[/ilink] (534 KB)
[hr]
Download Link
[ilink style="download" url="http://psdfreemium.com/download/884/"]Download PSD[/ilink] (534 KB)