Could this work?

[vaustin89]

I want to build a small amp for my brother. I made this diagram using a TDA2030, my problem is my design requires a bi-polar power supply to power my TDA2030, since I only have a 220v-12v transformer would my design work, I also intend on adding a 9V PS to power my pre-amp.http://i.imgur.com/KBGaJ.jpg  if this design works, what are the disadvantages of such design. Thank you  :tu:

[J M Fahey]

Use TDA2003 / TDA2002 / LM383 which is the single supply version.
Download http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&ved=0CEUQFjAF&url=http%3A%2F%2Fwww.st.com%2Finternet%2Fcom%2FTECHNICAL_RESOURCES%2FTECHNICAL_LITERATURE%2FDATASHEET%2FCD00000123.pdf&ei=v-yPT4f3JZSg8QSF1qWsBA&usg=AFQjCNH7LZqcdeBLtNlg5vN30cqsxplagg
They suggest a PCB layout.
You'll also need your 12VAC transformer, 4 1N4002 diodes (or a bridge, such as WN002) and a 2200/4700uFx25V main capacitor.
This will supply around 16VDC which is perfect.
The amp will drive 2 ohm loads, so you can use 2 4 ohm speakers if you wish. Or just use 4 ohms ... or just 8 if it's all you have.
Plenty of power anyway for a home amp.
Post what preamp you intend to use, probably you will need only a 9V zener, a resistor and a 100uF capacitor.
Or if you want the 9V regulator, go for it, but after it use a 10uF maximum capacitoe; a large 1000 or 2200 uF one will kill it quickly.

You can get the TDA2003 for sure; if not keep searching.
Avoid NTE parts and EBay oriental suppliers.

[vaustin89]

Thank you for clarifying, I haven't decided which pre-amp to use, I have 4558, TL072 and some transistor design. After building the power amp I'll just mix and match what sound my brother wants.