500W PA amplifier with Limiter

[apexaudio]

as i type this msg i am currently asssembling the protection circuit for the b500. One thing came up to mind cant i use a single supply source for the protection board , may be a single 15-0-15 TF. Use a small sugar cube relay of 12V and drive 12V DC fans for cooling.
What changes need to done to incorporate a single TF.

regards
Sekhar

Protect for B500 use 24V relay and 24V fan or two 12V in series. You can use single transformer 2x18vac for two protect in parallel or use some other protect circuit. Your heatsink is not enough for full power but with two fans will work.
Regards

 

[apexaudio]

@ apex
i would load the b500 with higher rail voltage bec. i want to drive it for sub woofer two 1000watts speaker 4ohms. what would be aproximate no. of power transistor per rail at 140 vdc. do i need to changed the pre- driver transistor?

thanks alot sir

Use H900 for more power is better than upgrade B500, or B500 with TL072 class H step driver.
Regards

 

[A square]

hello sir

pls tell me about transformer for b500x2.....

nd i use 2x12v fans..

what is the placement of 2 fans .....


thanx........

 

[apexaudio]

hello sir

pls tell me about transformer for b500x2.....

nd i use 2x12v fans..

what is the placement of 2 fans .....


thanx........

For stereo B500 use 1500W transformer sec: 2x60v + 2x18v for protect circuit.
Fans 2x12v conect in series one on front second on back side amp.
Regards

 

[A square]

ok thanx u very much sir......

 

[C3PO]

apex dual 18 sub

my apex sub, Fane 18xb loaded, painted with turboblue, nice bass

 

[A square]

looking very nice...

nice job sir....

thanx...

 

[apexaudio]

Very nice, can you post some high quality pictures.
Regards

 

[engel dela pena]

apex,
i started powering up my 2nd b500 then R27(22r) turn to brown slightly burn, i can even smell a burned resistor.
what would be the possible trouble?

 

[engel dela pena]

apex,
the scenario.
since i was using h900v2 pcb,i forgot to put jumper on neg. supply the one going to ir540
i already power up without jumper to neg. supply.Then after noticing the situation,i put then the jumper and power it up again,then the slight burning happen.it happen with zero v on the out.
I hope no collateral damage.

 

[engel dela pena]

apex,
got it already
post picture later
after two amp mount on chasis

 

[engel dela pena]

apex,
CORRECTED LAY OUT

apex,
tlo step driver
do i need heat sink upon testing

 

[apexaudio]

apex,
tlo step driver
do i need heat sink upon testing

You can testing short time without heatsink.

 

[engel dela pena]

apex,
thanks i better do my testing tomorrow,i need some rest,winding a torroid is not that easy,adding 2x48 and 2x18 to my trapo.
now i got 96-48-0-48-96 ac
using 4x 20,000uf 75vdc
i got medium volt +/-62.5 dc
HV +/- 125 dc
will my psu work?for my b500 & tlo step

 

[apexaudio]

apex,
thanks i better do my testing tomorrow,i need some rest,winding a torroid is not that easy,adding 2x48 and 2x18 to my trapo.
now i got 96-48-0-48-96 ac
using 4x 20,000uf 75vdc
i got medium volt +/-62.5 dc
HV +/- 125 dc
will my psu work?for my b500 & tlo step

Voltage is to high, you can winding more turns in series with primar to get lower voltage on secundar side of transformer.
Regards

 

[engel dela pena]

apex,
so this is the ideal voltage 120-60-0-60-120dc

 

[apexaudio]

apex,
so this is the ideal voltage 120-60-0-60-120dc

This is maximum voltage, I suggest to use transformer 4x35-40v ac.
Regards

 

[irvynejay]

Hello could anyone help me what can i replace or substitute for MJE340/MJE350,project almost done for test but sadly i cant find MJE340/350 pls anyone..

 

[noobie]

Hello could anyone help me what can i replace or substitute for MJE340/MJE350,project almost done for test but sadly i cant find MJE340/350 pls anyone..

as apex said you can use kse340/350

 

[irvynejay]

mje340/350

as apex said you can use kse340/350

yap i seen it on his post but still cant find those Kse and mje's any othr options