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How to Build an amplifier for cheap? Answered

I am a 17 year old teen with little pocket money and a beginner. I want to make an amplifier which can amplify an 8 inch subwoofer, two 8 inch speakers and 2 tweeters.



5 years ago

Thanks Guys for the response!!!
Please anybody give me a schematic for the amp with a list of components.
Thank you


Answer 5 years ago

A single amp schematic to drive an 8 inch subwoofer, two 8 inch speakers and
2 tweeters involves more electronics and cross-over networks then this site offers.

You should make a single preamp and three separate power amps for the
  1. subwoofer,
  2. the stereo speakers and 
  3. the tweeters
which is what an audio file puts in a single box.

What power levels, what class amplifiers ( A, B or C ),  do you want semi-conductors or
tubes are some selections you should make before asking for the schematic and a Bom.


5 years ago

As a beginner you don't want to lay out, worry about cross-talk and a host of other things.

Start with a $30 kit like this Velleman and learn how power and sound get together into electronics

Then if you like try asking for a circuit schematic and see if you can do it all.

BTW you will need a DC power supply to run your amplifier.

I started with kits and later made HiFi systems for girl friends.



5 years ago

You may want to look into making a "Gain Clone". I'm not sure if this will drive your sub but it might. Parts for these are usually in the $40 to $80 range.

Please make a battery powered one optimized for 48 volts and write us up an instructable :D


5 years ago

When you go for more than 1 speaker it no linger becomes cheap or easy. It would actually be cheaper to buy an amp for those speakers.

But if you really want to learn and build your own then start looking for schematics. First you will need to consider the impedance of the speakers in question as well as the total wattage they can handle. On the back of the speakers they should be marker with there impedance. Often they are 4 Ohms, 6 Ohms or 8 Ohm speakers. Just be aware building an amp isn't really a beginner project. Especially if your going for more than one speakers. Also most basic and easy to do amps won't supply more then a few watts to the speakers. If the speakers in question are car or home stereo speakers they probably need more then 10 or 20 watts, Especially the sub. You'll also want to consider build crossovers for the tweeters and sub so you isolate only the optimal frequencies for the speakers for better sound quality.