Getting there!

Select the background layer and create a new layer.

With the Elliptical Marquee Tool make a perfect circle a few pixels bigger than the "circle 2" layer.
Select a dark grey color as your foreground color and a light grey as your background color.

Select the Linear Gradient Tool and fill the selection going from the top to the bottom of your selection.
Deselect.

On the same layer change the Layer Mode from Normal to Difference.

Your image should now look like fig. 15.

Now it's time to add some details.

First I added some small bolts above the "circle 2" layer.

Then I created a new layer below the "small circle" layer.
On this layer I added some shadow using a soft brush (100 pixels) and black color.

Finally Finished!

This speaker looks great placed on a chrome surface.
Add some dirt and some inset lines and you're finally done.

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