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newbe needs help with amplifier project.

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newbe needs help with amplifier project.

Postby Djinn » Thu Feb 23, 2012 8:17 pm

i need some help with my project. i took apart a old computer speaker and removed the amp board. i than used it for my shelf speakers. im not sure how many watts it was pushing but it did push better than just my stereo alone. but im never satisfied with what i got. so i began by changing out the little capacitors that it had in it. and replacing them with the ones from an broken 1000w amp. i think they are a 35v 4700 and two 25v 3300s. and than i changed out the little diodes with much larger ones. after all that it pushes very hard! it burned up my shelf speakers! but they where only 15w each. so i hooked them up to some other speakers, 150w each. and they are loud! but i still cant turn it all the way up. i can only get around 1/2 volume. after1/2 volume it starts to distort. am i just not using big enough speakers? or is there something i did wrong? or is there still something i need to do? ive got access to all the parts i think i will need. i just dont know what i need to do. im dont understand a thing about ohms, volts, or anything else. only watts. and thats an easy one. i just want to know how i get crystal clear sound at full power. and i would like full power to be around 1000w, if not more. i would like to push as much power as i can.
if anyone can give me any advice i would be very thankful!!!!!
thanks to all!!!!!!!
Djinn
 
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Joined: Thu Feb 23, 2012 5:31 pm

Re: newbe needs help with amplifier project.

Postby pebe » Sat Feb 25, 2012 5:24 am

If you know about watts, then I should have thought it was obvious that you that you cannot get 1000W from an amplifier designed to give no more than a couple of watts to a computer speaker.

I think it was not the audio power that burned out your 15W speakers – I think you somehow got DC across the voice coils. If you, quote, ”dont understand a thing about ohms, volts, or anything else”, then you don’t stand much chance of making a working 1000W amplifier from bits and pieces.

My advice would be to buy a new 1000W amplifier or build one from a kit because experiments could well cost you dearly – by burning out your other speakers or giving you a nasty electrical shock.
pebe
 
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Location: Ellon, Scotland

Re: newbe needs help with amplifier project.

Postby Djinn » Mon Feb 27, 2012 5:19 am

well ive done some work with small clock radios in the past(thats what i started on. changing out capasiters and what not in order to gain in volume.) but ive never done anything as extensive as this. im using larger capacitors than i had ever been able to come across. and im afraid i didnt have any direct current at all. im using a 24v transformer. thats AC right? i may not be pushing 1000w, but im pushing over 200.i got some 200w kicker 12" sub-woofers friday. they sounded good!!! better than they did in my brothers car. and he had a 200w amp. I know what a speaker sounds like with a direct current running through it. no, i did it intentionaly. turned the volume up all the way and it just smoked the voice coils. i mean, why spend $ on a kit or amp when #1, i already have a 1000w boss chaos amp, #2 i can harvest the parts myself and with a little advice in a fer arias, build the thing myself. but thanks for your advice.
Djinn
 
Posts: 3
Joined: Thu Feb 23, 2012 5:31 pm

Re: newbe needs help with amplifier project.

Postby pebe » Mon Feb 27, 2012 8:01 am

You said you had "removed the amp board from an old computer speaker". They normally give a few watts. There is no way that you can "change a few capacitors" to get it to deliver 200W - let alone 1000W!

You may have a 24V transformer but that is rectified to DC to run the amp - they won't run on AC.
I, also, know what a speaker sounds like with DC going through it - a bump followed by silence.

If you are going to start playing with 1000W amplifiers, then it's safer to know what you are doing or leave well alone.
pebe
 
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Joined: Tue Dec 09, 2003 11:12 pm
Location: Ellon, Scotland

Re: newbe needs help with amplifier project.

Postby Djinn » Wed Feb 29, 2012 3:46 pm

im looking for help trying to make them better man, not advice on weather or not i should be doing it or not. if you could tell me how i can make it better, than i would me grateful. i know enough about electricity in general to not hurt myself. i may have learned the hard way, but i learned none the less. there is no 8 leg IC on the board, or i would have changed it out with the ones from the 1000w board. see if that would help. ill put some pics on after a while. let you see what im working with. i got to pull it out of the inclosure i put it in. thanks for you input.
Djinn
 
Posts: 3
Joined: Thu Feb 23, 2012 5:31 pm


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