Well guys I finally got my subs hooked up to my amp and nothing happened. I noticed the protection LED was on....so I started some basic diagnostics.

Checked power, ground, remote, etc and all was good.


I took out the speaker wires and RCA cables to put the amp in its basic state of power and ground.....and the protection light is still on.

Is this a shorted output transistor? This is the first time I've hooked the amp up. What do you guys think this is? What are my options?

I could either return it for a replacement (really don't want to b/c I'm tired of waiting to get this put in) or try to repair it myself. What would you do?

 

Check the fuses. Sometimes if your not careful you touch things that shouldnt touch and pop goes the fuse.

 

Forgot to mention that the fuses were fine. I went ahead and called Sonic and since the amp has a 2-year warranty they are going to check it out.

I asked if I could get an advance replacement (I'm in a hurry to get this put in) and he said since it was within the first 30 days that they would do that. I'll get the new one in a few days, send the old one back, they'll test it, and we're done.

Thanks for the help, Pork!

 

Like Pork said, check the fuses first and make sure your power wire and remote aren't shorted to ground somehow. If your fuse keeps blowing after verifying the connections then you have a shorted internal component, most likely a mosfet or transistor. I had a mosfet blow on my fosgate and it was a pain in the **** to replace because of the way they monted it to the heat sink. You should probably take it in for repair if that's the case. Good luck.

 

A MOSFET is a transistor

My bet's on a defective output stage. Just curious - if you disconnect the load, conect a voltmeter (or better yet, a scope) and turn the amp on, what do you see?

 

I said the fuses were fine--they don't blow. They are in perfect condition.


By load do you mean the speaker wires and RCA cables? If so then nothing irregular. Power and remote lead were receiving the proper voltage and the ground was fine--I double check it.

 

The speaker load. No inputs connected. Power only. Amp off. Connect scope/voltmeter to the output connectors. Power up the amp. With a digital scope (with memory), if there is an output stage short, you usually see a very brief transient ( +/- rail voltage) before protection is triggered. It's a current-sensing mechanism in most cases. Just curious - it's typically so brief that a DVM will not detect anyway unless it's a fast peak-hold type.

Good to know the manufacturer is taking care of you.

 

Ah I think I understand. If I had an oscilloscope I'd give it a try. I did check the output voltage on the speaker connections and there was nothing. That's what initially led me to believe it was an internal problem in the amp.


Yeah I'm really relieved that they are doing what they are. I've been told recently that their warranty program is terrible.

When I called I explained what was going on and he agreed that it didn't sound like an impedance issue--more like a defective amp. They were going to just have me ship this one back for testing but I told him I wanted to get this thing hooked up asap.

So they're covering shipping on a new unit and sending it tomorrow. Basically an "advanced replacement", as he called it. They charged me for it, but as soon as I send the old one back they will credit my account. If it tests fine, though, they are going to charge me a "testing fee". No biggie--I am pretty sure it's a problem with the amp--not my wiring. The guy I talked to agreed. So it's all working out.



Thanks for the help!

 

I agree..... sounds like an internal amp issue. Glad to hear SE is taking care of you. I've heard horror stories dealing with their warranty.

 

[QUOTE=mblouir;4064738]I said the fuses were fine--they don't blow. They are in perfect condition.

Sorry, when I replied your post wasn't there yet.





[QUOTE=MGDfan;4064675]A MOSFET is a transistor

Doh!! Yes it is, forgot to edit that before I posted. Hate it when I say something stupid. It's been one of those days for me.:o

Glad to hear you are able to return under warranty.

 

Wow you got lucky with SE, glad to hear it. A lot of times they will just be like "oh you installed it yourself and not by a professional, must be user error...no warranty."

I'm surprised the JL amp was DOA (or somewhat DOA). They are usually pretty reliable units.

Anyways, hope it works out.

 

It's all good. It's been one of those weeks for me.

Kenwood amp, actually. The XR-1S. It was a great deal compared to some of the other amps in the same price range. 350w to each sub is about exactly what I'm wanting to send the subs (to start with, anyway). Unfortunately "get what you pay for" seems to apply here. I told myself if it didn't send enough to the subs I'd upgrade it down the road with the comps, so we'll see.

Thanks bud!