Hi AndrewT and thanks for your prompt reply. Can u please tell me where are those instructions?
I had saw a table having a max voltage of +-85 with an output of 350W at 8Ω but i am not sure if really anyone have tested the amplifier in such voltage having not problems and also i havent found anywhere the approximate efficiency of the amplifier...
I had saw a table having a max voltage of +-85 with an output of 350W at 8Ω but i am not sure if really anyone have tested the amplifier in such voltage having not problems and also i havent found anywhere the approximate efficiency of the amplifier...
unless you test the finished amp using 8 ohms dummy load, you can not say 350 watts at 8 ohms...
this is because we do not know how beefy his power transformer is and how it sags under load.......
many times you see on schematics such labels as +/- 85 but it is usually not specified if this voltage is the no-load or fully loaded voltage, and then if the amp shares the same transformer, we are not sure if this voltage is taken to mean both channels fully loaded....
ultimately, power capacity is determined by the power supply, more specifically the power transformer...
Yep, i can understand what you mean.But i just ask if anyone have tried it on that voltage...Or just an advice on what personally anyone would recommend...
Also the efficiency! 🙂 🙂
Also the efficiency! 🙂 🙂
It works with 90 V by me.... more than 1 year but you will need more output devices
minimum should be 12 pcs. IRFP 460
6 pcs. in negative and 6 pcs. in positive rail
which transistor is good for the nmos200 247 for best performance.eg irfp250 ,irfp240,irfp450,.
each,... I prefer high power dissipation Mosfets like IRFP460
use high current driver like 2sa1837 / MJE15030 or similar mosfets have high gate capacite
after final test enjoy and rock your house !!!!!!!!!!!!!!!!
my NMOS is working with 90-95 V DC and really hard to beat in sound quality
Finally.... NMOS 350/500 kick out of the job a lot of Class D designs like IRS2092 in sound quality and robustness
really no way for class d only efficiency
nmos,
do you have single sided version of your pcb.?
do you use 6 pair in your amp with +/-90?
any pictures of your mighty nmos using irfp460
do you have single sided version of your pcb.?
do you use 6 pair in your amp with +/-90?
any pictures of your mighty nmos using irfp460
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No single sided available, singel sided not good idea
for Bass like PA with Full output power use 7 pairs
lor listening home @ HI FI speakers 1 pair is working too
nmos,
do practice using ferrite beads on fets gate?is this realy a good idea of eliminating parasitic oscillation?
do practice using ferrite beads on fets gate?is this realy a good idea of eliminating parasitic oscillation?
that's twice !
If the amp has a quiescent current of 60mA from each rail of a +-80Vdc dual polarity PSU then Pq=9.6W
If the output from the amplifier is ZERO Watts, what is the efficiency?
If the output is 0.1W, what is the efficiency?
If the output is 1.0W, what is the efficiency?
If you are a green plant person then don't use nor build electrical equipment.
for nmos350 irfp460 or irf260 is it ok? which is better?
and max secondary ac voltage of the transformer.
and max secondary ac voltage of the transformer.
for a normal mains supply the maximum capacitor voltage will be
Vsupply / Vrated of transformer primary * Vrated of transformer secondary * [1+regulation] * sqrt(2) -0.5V if using a single bridge rectifier
example 230:60+60Vac transformer with 5% regulation on a supply that could be 240Vac+6%.
254/230*60*[1+0.05]*1.414 - 0.5V = ~97.9Vdc
If the transformer regulation is more than 5%, or the mains tolerance is more than 6%, then 60Vac may not be safe with 100Vdc capacitors.
Vsupply / Vrated of transformer primary * Vrated of transformer secondary * [1+regulation] * sqrt(2) -0.5V if using a single bridge rectifier
example 230:60+60Vac transformer with 5% regulation on a supply that could be 240Vac+6%.
254/230*60*[1+0.05]*1.414 - 0.5V = ~97.9Vdc
If the transformer regulation is more than 5%, or the mains tolerance is more than 6%, then 60Vac may not be safe with 100Vdc capacitors.
If you are AndrewT its too difficult for you to make a guess in order to help a newbie to choose between a 800VA and a 1000VA transformer for an aplifier you have built at +-80VDC with 8Ω speakers...😀
Dont afraid! I wont kill u if you dont be too accurate... But it is quite obvious that i ask for the peak power and of course that i dont care to be too accurate...
Anyway thanks at least for answering...
Dont afraid! I wont kill u if you dont be too accurate... But it is quite obvious that i ask for the peak power and of course that i dont care to be too accurate...
Anyway thanks at least for answering...
can anybody share the latest working nmos350 one side pcb. irfp460 or irf260 which is better?
any recomended transistor for this?
any recomended transistor for this?
Hi a lot of PCB supplier offer double sided pcb with door to door service, cost is a few USD compare to single sided.
I prefer double side because PCB is smaller and you will have ground plane on TOP side
You can get my double side PCB gerber files for pcb supplier
Hi use IRFP460 easier to get by supplier and high Voltage you can push harder
IN my design IRFP460 is working
If you can get 1000 VA for similar cost take it, have test NMOS up to 100 V DC its working great amplifier.... amp is running hot but its normally for class AB
you will love the clear balance natural sound