Here's my CD player adapted from an old CDROM. It's got an amplifier and a power supply for the CD and its all contained in a nice clear plastic case. I added a connector for external speakers and there is just enough power in the TDA2615 stereo 6 watt amplifier to drive some big speakers that I had laying around. There are also small built-in speakers. An external audio input - a 3.5mm jack - can be used to plug-in anything with a standard earphone plug - eg. an iPod or MP3 player.
Step 1: The Amplfier
The amplifier circuit is from the TDA2615 datasheet. I just added the volume control.
Step 2: The Power Supply
Powered by an old laptop power supply - the laptop stopped working long ago but the power supply still works and its 19v output is just right to power my CD player. The CDROM takes 5v and 12v so I needed to reduce the input 19v from my power supply using voltage regulars. Of course you can use an old PC power supply but these are big, heavy and noisy. On the case of my CDROM it says that it draws 1.5 amps of both voltages. Each 78xx can supply 1 amp so I tried just connecting two in parallel for both the 5v and 12v supply. This worked fine for the 12v circuit but for the 5volts one 7805 got much hotter than the other and then one day it just went BANG. So for the final version I used a circuit I copied from here for the 5v circuit. I stayed with the 2 parallel 7812 ICs for the 12volts.
For my first version I soldered the 78xx's directly onto the board. This proved to be a bad idea when I needed to change things, so I used sockets from then on.
Just for fun I added LEDs on the 5v and 12v rails.
Step 3: The Case
The base is made of plywood, painted silver on the inside and black on the bottom and the edges. The top and sides made of clear acrylic. I bought a large sheet - 1220mm x 600mm x 2mm and have used it for several projects. It comes with a protective film on which I leave in place until I'm ready for the final assembly to try the avoid any scratches. You can cut it with a saw and then tidy up the edges with a file (or a wood plane works surprisingly well). But the best way to cut it is to score it with a Stanley knife then break it across the edge of your bench. However, you have to bend it a long way before it breaks and it doesn't always break cleanly along the line you have scored. Expect to waste a few pieces unless you're better at it than me. I also found it tends to split if I try using ordinary wood drills on it. The best way to cut holes is with a dremel style drill fitted with a fine grinding bit. For the slots I cut most of the hole with the dremel and then tidied the edges with a hand file.