Higher voltage than you need in a cap just means more cost/ bigger size for
no real return. 63 volts is a pretty common value for film caps.
As for etching a board, the start up cost is the problem. If you are only
going to do this one project, I would say do it on perfboard. If you are
planning on doing lots more projects, then I would say have a look at
learn to etch your own boards. Everything I do, I etch my own boards.
The "Iron On" method has the lowest start up cost but is the hardest
to get good results without lots of practice. Photo etching is pretty
easy to get good results but is more expensive to start up and the
presensitized board are more expensive. There are several threads and
tutorials on Head-Fi and on the web for both methods. I use photo etching.
Look for a transformer of at least 12 volts and maybe as high as 16 volts.
If you have more voltage it makes it easier to add a regulator to improve
the quality of the power supply. Regulators need a few extra volts to
do their job. Plan on your transformer/wall wort to be about 3 volts higher
than you think you will need. Remeber too, that the power supply voltage
you pick will have some effect of the power supply caps in you CMoy.
You will want caps rated about two times the voltage of your power supply.
