DC Servo MOSFET Amplifier

[132222]

Excuse me.
Why is the output MOSFET gate is 2.5 volts DC power.??

 

[carlmart]

I use TL071 instead pot for auto adjust DC offset, with C6 offset is +/-0.1mV and without C6 it's +/-1mV.

So C6 could be eliminated then.

IMHO, the whole reason for using a DC servo is to avoid a capacitor in the signal path and improve audio quality, isn't that so?

 

[apexaudio]

So C6 could be eliminated then.

IMHO, the whole reason for using a DC servo is to avoid a capacitor in the signal path and improve audio quality, isn't that so?

Auto offset adjust is adventage, no need to set with pot and measure...

 

[nix]

Amplifier for 1R load

Hi sir apex do you have pcb on this design because i want to try build this amp..

Thank you.

regards,
nix

 

[apexaudio]

Hi sir apex do you have pcb on this design because i want to try build this amp..

Thank you.

regards,
nix

No, use basic pcb for drive and another pcb on heatsink for outputs.
Regards

 

[apexaudio]

Excuse me.
Why is the output MOSFET gate is 2.5 volts DC power.??

Amp work in class B, with AB setup gate is on about 3,5 volts DC.

 

[wattaniya]

High efficiency (classH), high power (200W/8R peak) on small pcb this amp will be great for active speakers...

HI APEX SIR,
can u, share this pcb layout of this amp.

 

[apexaudio]

HI APEX SIR,
can u, share this pcb layout of this amp.

Pcb from post #53 ?

 

[wattaniya]

HI APEX SIR,
u shared h100,h150,h200,h210 schematics, can u share any one of these schematic with all component values,

pls check this pcb for errors and mark the component value.
thank u.

 

[apexaudio]

HI APEX SIR,
u shared h100,h150,h200,h210 schematics, can u share any one of these schematic with all component values,

pls check this pcb for errors and mark the component value.
thank u.

This pcb is for MPSA42/92 instead BF420/421...

 

[wattaniya]

This pcb is for MPSA42/92 instead BF420/421...

thanks apex sir for the reply.
can u share the schematic of this pcb with component value.
what is the dc rail voltage for this class h amp?

 

[oscarcito_]

hello apexaudio where I can find the pcb mounted the vumeter having the cabinet that you got as profile picture? thanks

 

[apexaudio]

This pcb is for MPSA42/92 instead BF420/421...

thanks apex sir for the reply.
can u share the schematic of this pcb with component value.
what is the dc rail voltage for this class h amp?

DC rail voltage for this amp is 70-35-0-35-70

 

[apexaudio]

hello apexaudio where I can find the pcb mounted the vumeter having the cabinet that you got as profile picture? thanks

You can't find this pcb, it's not shared.

 

[benchong]

Hi Mile,
I finished the board but I using IRF640 and 9640,
also use BC639,BC640 to instead the BF420,421
I had measure the bias just 3.4mA and the LED also not lit,
I also measure the voltage between the LED just 1.2V,
please let me know what can I do.

Thank a lot!

An externally hosted image should be here but it was not working when we last tested it.

 

[apexaudio]

Hi Mile,
I finished the board but I using IRF640 and 9640,
also use BC639,BC640 to instead the BF420,421
I had measure the bias just 3.4mA and the LED also not lit,
I also measure the voltage between the LED just 1.2V,
please let me know what can I do.

Thank a lot!

An externally hosted image should be here but it was not working when we last tested it.

Q1 and Q2 are BC556, and connect input gnd to psu gnd...

 

[andrewlebon]

This PSU and Protect circuit ca be used with any amplifier. Short-circuit protect based on Tandberg schematics is 100% efficacy.
Dear Apexaudio
greetings can this power supply be used with b500 TEF i mainly need
short circuit protect dc supply is 70 volts+/- 10 pairs 2sc5200 2sa1943 other than filter
caps what other changes are to be done or if possible can you please share any other short circuit protection which can work for this amp please can you help me
warm regards
andrew lebon

 

[irwanks]

Hello sir. Can i ask anything? What is the rating watt for 2v7 zener diode? are 327 and 337 for bc327 and bc337? are 420 and 421 for bf420 and bf421? Thank you.

 

[comasus]

High efficiency (classH), high power (200W/8R peak) on small pcb this amp will be great for active speakers...

Hi! Mile

this amp is suitable for 4ohms

 

[apexaudio]

Hi! Mile

this amp is suitable for 4ohms

Yes, with 60-30-0-30-60v dc rail voltage.