500W PA amplifier with Limiter

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B500 ROCK MY HOUSE

Thanks to Apex

I'm so happy now
my B500 now Playing USB thumbdrive & FM
power rail +/-70V DC
from 2 trafo @600VA 57V ac each
load 8r
its cool, not so hot
No Humm, no hiss
just the music
loud & clear
(I think heat sink is small so I don't go to 4r yet)

Some question,
Why I can't measure any voltage across 0r33 resistor when the volume minimum?
Any suggestion which component to be change?
attached image of some measurement

Also its need or not to add "Apex Speaker Terminal" on the output amp like AX series?
If need, any changes or its just same as AX Speaker Terminal?


Thanks
GBU & PEACE
 

Attachments

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  • PLAY FM.JPG
    PLAY FM.JPG
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  • HV+ & HV- 2.jpg
    HV+ & HV- 2.jpg
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  • TOP VIEW.JPG
    TOP VIEW.JPG
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Thanks to Apex

I'm so happy now
my B500 now Playing USB thumbdrive & FM
power rail +/-70V DC
from 2 trafo @600VA 57V ac each
load 8r
its cool, not so hot
No Humm, no hiss
just the music
loud & clear
(I think heat sink is small so I don't go to 4r yet)

Some question,
Why I can't measure any voltage across 0r33 resistor when the volume minimum?
Any suggestion which component to be change?
attached image of some measurement

Also its need or not to add "Apex Speaker Terminal" on the output amp like AX series?
If need, any changes or its just same as AX Speaker Terminal?


Thanks
GBU & PEACE

Nice work.
There is no voltage across 0R33 becouse outputs work in class B, use 1k pot instead R22 and set 10-20mV for work in class AB (BIAS 50mA).
Add 'Speaker Terminal' on any amp, there is DC protect (crow bar) and Zobel Network.
I like your MP3 player, I want to get one.
Regards
 
Nice work.
There is no voltage across 0R33 becouse outputs work in class B, use 1k pot instead R22 and set 10-20mV for work in class AB (BIAS 50mA).
Add 'Speaker Terminal' on any amp, there is DC protect (crow bar) and Zobel Network.
I like your MP3 player, I want to get one.
Regards
Oh that why,
I will work it in class AB later
for now its okay anyway
my speakers are subwoofers
they like this amp

Thanks again
 
Thanks to Apex

I'm so happy now
my B500 now Playing USB thumbdrive & FM
power rail +/-70V DC
from 2 trafo @600VA 57V ac each
load 8r
its cool, not so hot
No Humm, no hiss
just the music
loud & clear
(I think heat sink is small so I don't go to 4r yet)

Some question,
Why I can't measure any voltage across 0r33 resistor when the volume minimum?
Any suggestion which component to be change?
attached image of some measurement

Also its need or not to add "Apex Speaker Terminal" on the output amp like AX series?
If need, any changes or its just same as AX Speaker Terminal?


Thanks
GBU & PEACE

Hi JOHN, i want to know about your USB thumbdrive & FM did you build it (DIY) or bought it ?

i want that one for my amp... thank's
 
Hi JOHN, i want to know about your USB thumbdrive & FM did you build it (DIY) or bought it ?

i want that one for my amp... thank's

I bought it in Denpasar @ my uncle elec-shop.
Anyone want to buy from me ...? or want to trade it with IR2117 & some u fast diode that hard to find here.
I just have one of it left, want to give it to Sir Apex as a gift he...3x :):).
Wish he come to Bali, maybe some vacation.


Matur Suksma
 

Attachments

  • U player + IR.JPG
    U player + IR.JPG
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I bought it in Denpasar @ my uncle elec-shop.
Anyone want to buy from me ...? or want to trade it with IR2117 & some u fast diode that hard to find here.
I just have one of it left, want to give it to Sir Apex as a gift he...3x :):).
Wish he come to Bali, maybe some vacation.


Matur Suksma

o ic, there's any in other town, or just on your uncle store ? thank's
 
yes sir tony... it will be mounted overhead. one thing am planning to do is to make two of the speakers active... the other two will be on a passive mode and will be connected in parallel with the active one... any recommendations? i believe 1 b500 of sir apex can handle 2 12 inch instrumental speakers right?