JL Audio 800x1

[fragmental]

Hi all, looking for some advice on a JL Audio 800x1. I have a couple output fets bad(35n15g) in the output stage.

Should I be replacing all 8 with the same date code and do I need to do any setup for biasing? I`ve read a few post about adjusting a pot fully ccw and bringing it up till idle current increases slightly. There is a pot on a vertical board close to the fets and one on the opposite side of the amp. If I do need to do this adjustment which pot?

Thanks Les

[joesch1999]

I don't think you need to mess with the pot, I had to replace those same fets in the same amp, was fine after I did it, I did replace them all though I think they are inexpensive so might be worth it. date code should not matter just check voltage and such, I got my fets from digi-key they worked great, almost forgot check the driver fets as well, I had to replace a couple of those, there is a jfet a j108 or j111 in there it will measure bad but it's normally not works when power is applied to it.

[joesch1999]

this amp is the e1800 right?

[fragmental]

Found it on the side A 1800 class d Mono.

Looks like 300 minimum order from Digikey and they are non stock. I`m sure I can come up with them somewhere.... unless there is a good sub for them?

[joesch1999]

ah thats right they were being discontinued when I ordered them try mouser

[Perry Babin]

The outputs:
NTP35N15G for ON Semiconductor | Arrow Electronics Components

Don't turn the pot fully CCW. This isn't a class AB amp. I think the one on the driver board is for the over-current threshold. The one on the main board is the DC offset.