150W MOSFET Amplifier with IRFP250x2

[cook77]

I have a question: if I make this modifications , drivers will stay cooler .
Would it afect the sound quality?

 

[thole]

Its works, with 50v dc & 20mv bias(for test). I will push bias more higher again.
Many thanks to mr. Mile for schematic & sonal kunal for pcb design.
Please advice for optimmum bias & voltage.
How many watt can deliver from this amp, with 3pair irfp260n, datasheet say 300watt dissipation?


Thanks
Regards

 

[apexaudio]

Its works, with 50v dc & 20mv bias(for test). I will push bias more higher again.
Many thanks to mr. Mile for schematic & sonal kunal for pcb design.
Please advice for optimmum bias & voltage.
How many watt can deliver from this amp, with 3pair irfp260n, datasheet say 300watt dissipation?


Thanks
Regards
View attachment 468323

Nice work, about 300W/4R with +/-75V
Regards

 

[thole]

Update!! Use +-56volt DC, bias 35mv. No hum, noise, & simple powerfull amp. I use this amp to handle 10" 350watt 2ohm speaker.
Mr. Mile, Can i use 2sd600/D600K instead BD139?(many fake BD series in here)

Thanks
Regard

 

[thimios]

Update!! Use +-56volt DC, bias 35mv. No hum, noise, & simple powerfull amp. I use this amp to handle 10" 350watt 2ohm speaker.
Mr. Mile, Can i use 2sd600/D600K instead BD139?(many fake BD series in here)

Thanks
Regard

It's a working amplifier,so it's time for pcb posting!😉

 

[apexaudio]

Update!! Use +-56volt DC, bias 35mv. No hum, noise, & simple powerfull amp. I use this amp to handle 10" 350watt 2ohm speaker.
Mr. Mile, Can i use 2sd600/D600K instead BD139?(many fake BD series in here)

Thanks
Regard

Yes many TO126 transistors can be use instead BD139... 2SD669, MJE340...
Regards

 

[thole]

PCB NX-400

It's a working amplifier,so it's time for pcb posting!😉

Many thanx to Sunal Kunal, he was made this.


Thanks
Regard

 

[thole]

NX-14

Mr Miles, i want to ask max value for C4 & C5, can it change with 47uf? i want to build second Nx-400, but my stock 22uf is empty.


Thanks
Regards

 

[apexaudio]

Mr Miles, i want to ask max value for C4 & C5, can it change with 47uf? i want to build second Nx-400, but my stock 22uf is empty.


Thanks
Regards

Use any value over 22uF
Regards

 

[sonal kunal]

Nice work thole, amp is able to drive 2ohm load at 56v.
BD139, BD140 fakes, I only buy CDIL make BD139, BD140 other manufacturer marking ones are mostly fake here. Still have few pairs of grey Philips ones.

All files for building this amp.

 

[thole]

Problem found

After 2 hour running, there is something wrong.
Some advice will be acepted.

Thanks
Regards

 

[Samuel Jayaraj]

Adjust Source resistors for equal voltage drop.

 

[Vrystaat]

Or match the fets.

 

[apexaudio]

Mosfet matching

 

[thole]

Thank you for the advice, i'll try one by one.


Thanx
Regards

 

[Vrystaat]

Apex, at what current do you suggest to match IRFP460 fets?

 

[Samuel Jayaraj]

Matching will help. But since you said that interchanging the Mosfets resulted in devices in the same position heating up, I think the Source resistors are the culprits.

 

[altclick]

Sonal,
Thanks for the files

 

[sonal kunal]

R3 10K in schematic is labeled 22K on layout 😱. Those who downloaded sprint layout file can edit it.

Corrected pdf files.

 

[thole]

My Nx-14
View attachment 470070
View attachment 470071
View attachment 470072