Step One

Create a new canvas, with width 200px and height 300px, and click OK, then turn on the rulers (ctrl+r)
Step Two

Next, create a new layer, and drag out some rulers, to the horizontal centre, and just above the vertical centre. Now, drag out a circular selection from where the lines intersect, whilst holding shift+alt so that the circle is approximately 25 px high and wide. Then, select the gradient tool, and fill the selection with a linear gradient, going from #5B6660 to BCCCCC from bottom to top. The image to the left shows what you should have so far.
Step Three

Now, we’re going to style that circle, first with an inner shadow with these settings: Blending: Overlay Color: White Opacity: 75% Angle: 90 Distance: 6 Choke: 0 Size: 9 Noise: 0
Step Four

Next an outer glow with these settings: Blending: Normal Opacity: 60% Noise: 0 Color: Black (solid) Technique: Softer Spread: 0 Size: 5 Range: 50 Jitter: 0
Step Five

Finally, an inner glow… Blending: Normal Opacity: 31 Noise: 0 Technique Softer Source: edge Choke: 0 Jitter: 0 Range: 50
Step Six

Now, create a new layer, and place it under the previous layer (so it is just above the background layer) and drag another circular selection, say 60px height and width, and fill with a linear gradient, A2ABAA –> 5D6663, bottom–>top. Now, apply an inner shadow to the layer using layer styles with these settings: Blending: Lighten Color: White Opacity: 35% Angle: -90 Distance: 2 Choke: 0 Size: 1 Noise: 0
Step Seven

The image to the left shows what we have so far (hopefully!)
Step Eight

Next, create another new layer, and again, place it under all the previous ones, and again, drag a circular selection, this one about 85px tall and wide, and fill it with #414B4A Now, onto the obligatory layer styles… Inner Shadow Blending: normal Color: White Opacity: 23% Angle: 90 Distance: 5 Size: 5 Noise: 0
Step Nine

Next, a Gradient Overlay Blending: Normal Opacity: 29% Style: Radial Align with layer: checked Angle: 90 Scale: 100 Gradient - see image below
Step Ten

Now, apply a Stroke Size: 2 Position: Outside Blend: Normal Opacity: 100% Color: #343F41
Step Eleven

Now, can you guess? we’re going to create a new layer, place it under the previous ones, and shift+alt drag a circular selection from the center, this one about 112px high and wide. Now, gradient fill the selection with a linear gradient, #898989 to #ECF0EF from top to bottom. Now, do a gaussian blur of 0.5% (filter–blur–gaussian blur) and our speaker is finished! It will now look like the image to the left.
Step Twelve

You should now put something behind it, so I would drag another circle and fill it with a gray color like #B0B0B0, as I have done in the image to the left.
Conclusion

Now… EXPERIMENT! try and introduce this to another interface, here is an example of this:

Here is one example of a variation on this tutorial, by www.spyderbyte.ca