Cerwin Vega Stealth 500.4

[ray9043]

Hi everyone

I have a long time ago a stealth class d 4 channel amp. I bought all fault components and replace it. 4 irs2092, 8 irf540z and 4 irf3205.
The amp sounds great but one channel witout output. I cant found the real problem in the preamp area, i put the green wire for test. All 4 channel works great but the 10 ohm resistor inside the white circule gets veryyy hot, it smells a lot. So i test only for about 5 minutes and wait for cool down.

I cant find the diagram, the only thing i know about that resistor, is part of the 12 volt regulator. It conect one side to speakers ground, the other to a rs1m diode then to the input of the lm7812.

Anyone with a diagram or a idea of this??

Thanks

 

[ray9043]

Picture

 

[Perry Babin]

Does that resistor get hot with no audio?

Did you pull the resistor to see if it was within tolerance?

 

[ray9043]

Gets hot anytime, playing audio or not. Yes its ok, 10 omh

 

[Perry Babin]

Draw a diagram of the regulator circuit with the resistor, the diode and the 7812.

The heating may be normal. A resistor will produce odor when it heats up. Even dust or skin oil will smell when heated.

 

[ray9043]

Picture

 

[Perry Babin]

Do you get rail-rail oscillation on the output FETs of the dead channel?

Does the IRS2092 get hot in that channel?

 

[ray9043]

All 4 channel plays fine. Problem on the front preamp card solved with a jumper for the moment. Nothing hot, only the 10 ohm resistor

 

[Perry Babin]

What's the voltage drop across the resistor?

 

[ray9043]

11v across the resistor

 

[Perry Babin]

That means that the regulator has about 1 amp passing through it. How hot is the 7813 regulator getting?

 

[ray9043]

all 4 irs2092 replaced, 8 irf540 outputs mosfets. 12v regulator repalced. the 100 ohm resistor replaced with a 2w ceramic resistor.

the amp plays fine all 4 channel, resistor gets hot but its fine.