You will make 4 amplifiers and connect 4 ohm speakers so you can have 4x250w?
That would be vary scary and loud, especially if you by PA speakers with at least 95db!
Then, just one channel (lets say mid-high) will be 98db because of 2 woofers. Then, ad the magic of active crossover which gives more space for speaker to breath so you can pump even more power, ideally twice the power! that is 3 db more!
I had 4x130w and active crossover at 350hz. At 350hz the power is equal, 50% to bas and 50% to mid-high. So, 130w for bas and 130w for mid-high. That is total of 260wats. In literature they say that this is equal to 520w per channel, for regular box with passive crossover and just one amplifier.... The point here is that it will be much louder!
I was so surprised how loud this setup can be!
Another thing, are you planing to make 4 amps in one box? The transformer will be VERY big! At least 1500VA!
Better is to make two separate stereo amplifiers. Mine was all in one and it was really heavy (having two 400VA toroids )
That would be vary scary and loud, especially if you by PA speakers with at least 95db!
Then, just one channel (lets say mid-high) will be 98db because of 2 woofers. Then, ad the magic of active crossover which gives more space for speaker to breath so you can pump even more power, ideally twice the power! that is 3 db more!I had 4x130w and active crossover at 350hz. At 350hz the power is equal, 50% to bas and 50% to mid-high. So, 130w for bas and 130w for mid-high. That is total of 260wats. In literature they say that this is equal to 520w per channel, for regular box with passive crossover and just one amplifier.... The point here is that it will be much louder!
I was so surprised how loud this setup can be!
Another thing, are you planing to make 4 amps in one box? The transformer will be VERY big! At least 1500VA!
Better is to make two separate stereo amplifiers. Mine was all in one and it was really heavy (having two 400VA toroids
)Hey no dude...not all in on BOX 
Am plannin to make 4 mono amps with seperate cabinets.
40-0-40 @7 amps transformer, 4 x 22000 uf filter capacitors in each cabinet.
An am making wooden bodies, giving it a Vintage look
The advantage of mono amps is that i am more scalable and more redundant.
You see any disadvntage in this ?
Thanks for the reply.
Am plannin to make 4 mono amps with seperate cabinets.
40-0-40 @7 amps transformer, 4 x 22000 uf filter capacitors in each cabinet.
An am making wooden bodies, giving it a Vintage look
The advantage of mono amps is that i am more scalable and more redundant.
You see any disadvntage in this ?
Thanks for the reply.
Hi,
40Vac will give about 55Vdc to 60Vdc at the amplifier.
A BJT amp using these supplies will give between 250W to 320W into 4r0 if the components are well proportioned to give good value. 22mF is perfect for extended low bass into 8ohm loading. I recommend double this smoothing for 4ohm loading. If you do not require sub-bass performance then the tiny bit lost at the bottom end from using 22mF smoothing should be tolerable.
Your two 8ohm drivers when paralleled give an effective 4ohm load.
Make the output stage and the driver stage strong enough to drive a 4ohm reactive speaker load.
40Vac will give about 55Vdc to 60Vdc at the amplifier.
A BJT amp using these supplies will give between 250W to 320W into 4r0 if the components are well proportioned to give good value. 22mF is perfect for extended low bass into 8ohm loading. I recommend double this smoothing for 4ohm loading. If you do not require sub-bass performance then the tiny bit lost at the bottom end from using 22mF smoothing should be tolerable.
Your two 8ohm drivers when paralleled give an effective 4ohm load.
Make the output stage and the driver stage strong enough to drive a 4ohm reactive speaker load.
Help!
Hi!
I want to make this M250 amplifier for my studies on school.
I’ve seen that there are 2 PCB’s for this?!
(http://www.diyaudio.com/forums/attachment.php?s=&postid=750570&stamp=1130104082 and http://www.diyaudio.com/forums/attachment.php?s=&postid=1300383&stamp=1189664656 )
I prefer the second one because it’s more clear than the first to me actually
Does anyone has one of these pcb’s in big (or digital) for making it, or does anyone have an idea where I can buy them?
Thanks!
Hi!
I want to make this M250 amplifier for my studies on school.
I’ve seen that there are 2 PCB’s for this?!
(http://www.diyaudio.com/forums/attachment.php?s=&postid=750570&stamp=1130104082 and http://www.diyaudio.com/forums/attachment.php?s=&postid=1300383&stamp=1189664656 )
I prefer the second one because it’s more clear than the first to me actually
Does anyone has one of these pcb’s in big (or digital) for making it, or does anyone have an idea where I can buy them?
Thanks!
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.