JL Audio 300/4

[caraudioguy2100]

The pots that sit by the audio driverboards are they to adjust the bias or the Dc offset ?

 

[Perry Babin]

Bias

 

[caraudioguy2100]

Ok I replaced the outputs in 1 channel since they were defective .

The amps low ohm light is still on and the channel will not bias and the amp draws 20 amps of current

 

[Perry Babin]

Do all of the LEDs light up on the driver boards if you apply remote for a couple of seconds then remove it?

 

[DerSamoaner]

JL Audio 300/4 BIAS

This could be helpful.

 

[caraudioguy2100]

All of the leds light up on the audio driver board .

I resoldered all of the connections on it and still have an issue .

The outputs get to hot to touch within 3 secs of powering up .

Any common problems besides the solder connections on the audio board. ?

 

[Perry Babin]

Do the outputs get hot with the bias set fully CCW?

 

[caraudioguy2100]

Yes

 

[Perry Babin]

All channels?

 

[caraudioguy2100]

Just 1 channel left front channel

 

[Perry Babin]

Is that the channel you repaired?

Did you use exact replacement FETs?

 

[caraudioguy2100]

I used IRF540 just like all the other channels .

This is the channel that has has issues since I received the amp .

 

[Perry Babin]

If you clamp the outputs to the heatsink, will the channel produce the same output (clip symmetrically at the rails) as the other channels? No load.

 

[caraudioguy2100]

I’m gonna have to remove the outputs out of all channels since now the low ohm led is lit and no channels will bias

 

[caraudioguy2100]

Something is still wrong with the driverboard or on the main board if I put that driverboard in the amp the low ohm light comes on