500W PA amplifier with Limiter

hi apex,
it would be nice if you check also the values and make a remarks on the pcb i make so that i can finalize it. another thing is, on your scheamtic you have 2x220n in series while in the pcb you have only 1x220n.

regards,
coolet

Ok, I will check. I use 100nF/250V instead 2x220nF in series becouse connect two 220nF/100V caps in series you get 110nF/200V.
Regards
 
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Hi! I'm new here, but I read through this thread (all the pages) and I decided to build this amp (B500). But on the last few pages something went foggy for me...this amp operates in class AB, delivers 500W to 4ohms (with proper supply), and for this, I need a transformer with 2x50 or 2x55VAC rating. But for this I don't need this class H step driver, am I right? I only need the transformer, a bridge rectifier, big caps, and this PA hooked up. Sorry for this really dumb question, but I got confused, when I saw the step driver in this thread.
Greetings from Hungary!
 
B500 not use step driver. With step driver you have new amp in class H like H900, but I suggest to use protection with this amp not just PSU.
Regards

apexaudio: Thank you for everything, of course I will use the protect circuit, that you suggested. And as many of us, also I would like to say THANK YOU for everything, you gave us so many schematics and advice - as I read the previous posts, threads.
And, when my amp will be ready, I would be happy, if I could post pics here of the final amplifier.
Bye
 
apexaudio: Thank you for everything, of course I will use the protect circuit, that you suggested. And as many of us, also I would like to say THANK YOU for everything, you gave us so many schematics and advice - as I read the previous posts, threads.
And, when my amp will be ready, I would be happy, if I could post pics here of the final amplifier.
Bye

Do you considering to build some simplier amp like 100W Hi-Fi for start?
Regards
 
Do you considering to build some simplier amp like 100W Hi-Fi for start?
Regards

Thanks, for trying to avoid me from failure, but I'm not as newbie as it sounded from my first post. I have been learning electronics on my own (in Hungary we say 'autodidakta mode') and I would like to say, that (I hope) I understand, how this amp works. When I first started building electronics, I started off with a TDAxxxx IC amplifier. It was a great thing that it worked as I plugged it into the socket. Since then, i built and repaired about 10-15 amplifiers and so many other circuits. Now, I would like to build this 'monster', as it is compared to my projects till now. I have an old 2U amplifier's case, I start with repainting it and preparing it for the 2 amplifier modules.
As soon as I achieve some advance, and if anyone interested here in my project, I make photos and post here.

bye
 
Thanks, for trying to avoid me from failure, but I'm not as newbie as it sounded from my first post. I have been learning electronics on my own (in Hungary we say 'autodidakta mode') and I would like to say, that (I hope) I understand, how this amp works. When I first started building electronics, I started off with a TDAxxxx IC amplifier. It was a great thing that it worked as I plugged it into the socket. Since then, i built and repaired about 10-15 amplifiers and so many other circuits. Now, I would like to build this 'monster', as it is compared to my projects till now. I have an old 2U amplifier's case, I start with repainting it and preparing it for the 2 amplifier modules.
As soon as I achieve some advance, and if anyone interested here in my project, I make photos and post here.

bye

This is not 'monster', this is simple medium power PA amplifier with limiter, and useing OP amp in input as AC buffer and DC servo is great adventage of this circuit.
Many diyers will be interested to see your work, please post photos here.
Regards
 
This is not 'monster', this is simple medium power PA amplifier with limiter, and useing OP amp in input as AC buffer and DC servo is great adventage of this circuit.
Many diyers will be interested to see your work, please post photos here.
Regards

Ok, I will post photos. I used the word 'monster' compared to my amps that I built so far, because I haven't built stronger amp than 2x150W, so it will be my first great project.
Thanks, and if I need some help, I will post here.
bye
 
Many brands use 2SC4793/2SA1837 as drivers. I use it for drive 3 pair outputs, PHONIC P3000 use it for drive 6 pair outputs...

can i use 2sc2581/2sa1106 for the drivers and c4793/a1837 in place of mje340/350???...
 

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hi apexaudio
greetings trying to make this amplifier h class with tlo72
step driver pcb and have made your dc protect will use with this amplifier
will it work main i need dc protect and overload detect .
thanking you
andrew lebon
 

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hi apexaudio
greetings trying to make this amplifier h class with tlo72
step driver pcb and have made your dc protect will use with this amplifier
will it work main i need dc protect and overload detect .
thanking you
andrew lebon

You must add parts around 2N5401 for overcurrent detect, or parts around NSL32 for limiter. DC protect will work with any amp.
Regards