poweramp schematics

[led_zeppelin]

Hi... as a student, affording high output poweramps is a definate no no... and as a musician i could use a few. i have a technology scholarship for use in school, so building my own looks like the best idea... i've looked at schematics before, but when it comes to aquire components i seem to be haing difficulty getting parts (like o/p transistors/fets) and am never to sure on what equivalents may be plausible... (mainly because all schematics i find seem to be a touch dated...)

Basically i want to build a decent 400w a side stereo amp... (or in that region (300rms?)) but cant find a decent schematic, or anyone with the know how to help me. As i don't like shoving 100v at 6 amps down my arms i'm a bit unwilling to 'trial and error', not to mention i cant afford to. could anyone help me? or point me in the right direction... with uk components that i can get?

Also, as a 1000va transformer is nigh on £50, is it not easier to use 2x500va?

Cheers, and thanks to all the people on this forum for their expert knowledge... i have searched far and wide for only a fraction of know how that is on this forum!

Matt

 

[UrSv]

For that power I suggest looking at:

http://www.aussieamplifiers.com/

Some people here have built them and you may find tons of info if you search on any of the names here.

 

[matth]

I can recommend the 500Watt amp I built a while ago for PA.
All the parts are available from RS, Maplins etc and the output can be had through onsemis samples program.
I have posted lots of info in these two threads:

http://www.diyaudio.com/forums/showthread.php?s=&threadid=18478
http://www.diyaudio.com/forums/showthread.php?s=&threadid=19652

I can't see that two 500VA tranfos are going to be cheaper than one 1KVA one. But if you already have them then there no problem you can just go dual mono block.

N.B. to get the power your looking for the silcon chip amps in the above threads can be run at lower supply rails, this would have the benifit of making the amp almost bullet proof.

 

[led_zeppelin]

what probs did you have when building the amp? and can i run it on 55-0-55 1kva? and was it hard to set up/balance? i've never built one before, so i am unsure on how to set up... but do have access to equipment due to being in school....

 

[li_gangyi]

when you are at htis kinda power..you have to be careful..every small mistake...like a solder splash..can result in lotsa stuff being burtn..so it's best to check and recheck...only then power up with a lower voltage and test..if it works out well...PUNCH IT~!!!

 

[led_zeppelin]

can someone explain all this talk of oscilation to me? there is only 1 pot on the schematic, so is it basically just a case of setting this pot correctly? as in school i have access to osciloscopes and sig gens etc... so with a little info will this be the easier part of building the amp? and thanks for the idea regarding on semiconductor... they're sending me all the op's and driver transistors as we speak!

Thanks again!!

matt