Take the next tool 
to continue creating the loudspeaker of the audio system to be:
Blending Options-Gradient Overlay
Gradient's parameters:
Blending Options-Pattern Overlay
Using the next instrument , create the central part of the loudspeaker:
Blending Options-Bevel and Emboss
Blending Options-Gradient Overlay
Gradient's parameters:
Blending Options-Stroke
Using the previous instrument, it's possible to draw the mobile ring of the loudspeaker.
First we need to create the outside edges of the ring and then, clicking on the Alt button, we may erase the inside ring's part.
Blending Options-Outer Glow
Blending Options-Bevel and Emboss
Blending Options-Gradient Overlay
