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:

i have some question here, would be glad if all of them will be answered.

1.for example I have 2 amplifiers one is a 50w in a 2x12 stack the other is a 30w connected to a 4x12, which will be louder? and why?

2.How critical is the sound on the size of a cabinet? for example a 4x12 marshall, what would happen if i increase or decrease the size proportionally of the cabinet, would it affect the tone?

3.if a guitar head say it allows 8ohms and i plug a cabinet that is more than the specified, would it affect the loudness?

4.has there been a amp head where you can hook up multiple cabinets?

misc question-->is it possible to run 2 or more pre-amps through one power amp? if yes, then what are some of the thing that should be considered?

hello, i need an opinion about this, i have started to build both a guitar and bass amp, well i have finished the preamp section for both, my problem now is the power amp, my guitar amp should be around 50-75w and my bass could be 100-150w.
would the power amp section of this design be good for bass,  http://sound.westhost.com/project27.htm, i have heard good feed backs on this project for guitar, not sure about the bass.... i'm more concerned on the power-amp section..
and can someone explain the difference between the speakers used in guitar amps and bass amps? :duh
thanks for any input in advance. :tu: