anyone help build a subwoofer amp?

cyberbear

hey guys,
im tryin to build an amp!
i picked up two 200 watt speakers! problem is i dont have an amp!
i think it would be intersting to build one or two!
anyone got any hints? ideas on how to go about it?
any links to sites which could help?
am i just starting too high? thanks a lot!

speaker specs: 200w 4 ohm!

cnocbui

http://www.diyaudio.com/

I think it would be cheaper to buy an amp, if cost is a factor in your thinking about building one.

Mains powered amps are usually rated for driving 8 ohm speakers, so a 100w amp should be all you require to deliver 200w to a 4ohm speaker.

ZENER

cnocbui wrote: »

http://www.diyaudio.com/

I think it would be cheaper to buy an amp, if cost is a factor in your thinking about building one.

Maplin do MOS-FET Amplifier kits up to about 200Watts The kits are cheap enough. The expensive bit is the power-supply and transformer

Mains powered amps are usually rated for driving 8 ohm speakers, so a 100w amp should be all you require to deliver 200w to a 4ohm speaker.

There's something wrong with that logic I think. A 100 watt amp > 8 ohm speaker will drive a 4 ohm speaker at higher power, but it's limited by the capacity of its power supply and the electrical characteristics of the output transistors. What you're suggesting is that a 100 watt amp in 8 ohms (3.5 amps approx) can then deliver 200 watts into 4 ohms (7.1 amps approx). I doubt it somehow ?

Ken

cyberbear

zener : you are sayin it is possible and worth while doin?
cnocbiu: how much would an amp cost to buy for theese? how much to build? thanks!

ZENER

A 200 watt Amplifier Kit is available for about 25 euro in Maplin in Blanchardstown SC.

This is the trafo required.

You'll also need a Bridge Rectifier and some large smoothing Capacitors and a substantial heatsink if you intend driving it hard.

Also note that the RMS output is only 100W into 4 ohms and 70W into 8 ohms.

Only you can decide if it's worth building, can you manage a soldering iron ? Do you have any experience of electricity or electronics ?

Ken

cyberbear

yes i can use a solder iron! ive done some work with earphones and simple circuits but im takin this to get experience! i can get help so i dont think it should be a problem in building it as long as the words arent to complicated! :P