Why isn't it working?!?

[c_hayhurst 10+ year member]

I have a Rockford Fosgate T5002 Power Amp that is 2 years old and it has worked flawlessly until yesterday. It is driving one RE 12" SE sub, wired mono. Here's what has happened:

It would cut in and out every 5 seconds. The amp is the second amp in a 2-amp daisy chain. The first amp works fine, which drives my four 6" speakers. The RF's power light comes on like usual, and neither the Thermal or Protect lights come on (which is a good thing).

Then today, the sub won't run at all, while the RF amp's power light is on, but the Thermal and Protect lights do not come on.

I disconnected the sub and checked the connections on the speaker and re-seated the speaker-wire connections on the amp. The sub still won't work.

What else can I check to find the problem? The speaker wires aren't cracked.

I have a multimeter that tests for DC, AC, amperage and ohms. Can I use this to test the amp?

I loathe the idea to take the amp to a dealer and pay them $33 for a bench test.

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[dleccord 5,000+ posts]

something wrong with the sub?

 

[zachzchw 5,000+ posts]

By daisy chained, do you mean the amps are strapped?

 

[c_hayhurst 10+ year member]

By daisy chained, do you mean the amps are strapped?

I mean the second amp is connected to the first amp via a pass-through connection. The first amp runs just the 6" speakers, the 2nd amp runs just the sub.

 

[c_hayhurst 10+ year member]

Well, now I'm wondering:

Maybe it is something wrong with the sub. How do I test it?

And again, does anyone know how to do a DIY bench test for the amp?

Could I just switch the 6" speaker wires from the first amp to the second amp? It has 75Wx2 and the 6" speakers run at 50W RMS/100W peak, so they can handle a test run.

 

[Hydrastas 10+ year member]

yeah, might as well test the RF amp with a 6" and test the sub on the other amp, to at least see if either works...maybe try running the rcas straight to the sub amp instead of chaining it, it might not like the lowered signal from daisy chainin...

 

[c_hayhurst 10+ year member]

Well, here's the deal:

I tested the RF amp by re-wiring the sub to it and connecting the sub directly to the amp which drives the 6" speakers. The sub works fine on the other amp, so I tested the wiring and electrical performance of the RF amp with an ohmmeter/voltmeter.

In picture 1, this is how the sub has always been wired and nothing has changed. I rewired the sub to the positions in pictures 2 and 3. In piture 2, the sub worked, but only used one channel's output. In picture 3, the sub made this weird, loud rumbling sound. Then I put a ohmmeter/voltmeter into the terminals used to bridge the amp. The ohmmeter showed 1 ohm and 40 DC volts. When I went to put the wires back in like picture 1, the sub also made that weird, loud rumbling sound.

I tested the other terminals with the ohmmeter/voltmeter, and then all of a sudden, all the speakers made this God-awful hissing and popping noise in all the speakers and from teh RF amp itself!

I completely disconnected the RF amp and the hissing and popping stopped.

Then, I reconnected just the RF amp to the power supply but to no speakers;it was totally isolated from the speakers or other amp. Now, the loud hissing/popping sound came directly from the RF amp! The power light would glow, but was quite dim. The Thermal and Protect lights did not light up.

I'm not sure, but I thought I got a whiff of something burning, too and the heat sinks got quite warm- warmer than the other amp when it was on for roughly the same amount of time.

Also, in picture 4, the ground wire is two-toned-copper on the outside strands, silver on the inside strands. Is that normal, or did something happen to make the wire's color change from its normal copper color?

So, now I completely removed all wiring from the RF amp- no speaker, no power supply, no remote, no ground.

I think the RF amp is dead. What do you think?

What should I do with it now? Would it still be worth it to shell out the $33 to have it bench tested? Is it repairable?

 

[c_hayhurst 10+ year member]

You know what?

I just realized: The first amp I have is a DEI Audio amp made in 1997 and has been in 3 cars and one 45mph rear-end collision and it still works perfectly. Yet, that **** RF amp is barely 2 years old and it's already dead. That demonstrates some crappy product quality.

Has anyone else experienced such a short lifespan of an amp? I don't run it hard; it runs 300W RMS on a speaker that is built for 600W RMS, 1200W peak. Would this lead to the amp burning out?

 

[sadams04 10+ year member]

Running it like that would not cause it to go bad unless it was wired for too low of an impedence. Sounds like you got other problems. Maybe dead.

I hear ya on the old stuff. I have two good amps that were purchased in 1998 and have been delivering 50x4 and 420x1 without a single problem. The good stuff does last.

 

[c_hayhurst 10+ year member]

Running it like that would not cause it to go bad unless it was wired for too low of an impedence. Sounds like you got other problems. Maybe dead.
I hear ya on the old stuff. I have two good amps that were purchased in 1998 and have been delivering 50x4 and 420x1 without a single problem. The good stuff does last.

Well, I was running a 2 Ohm load, which the manufacturer stated was stable for that amp. In fact, I called and emailed RF to get confirmations before I even bought the amp. And I checked the amp's product specifications on 3 different websites, in conjunction with getting confirmation on this forum.

Yeah, I just ran across a post from someone who says they don't like DEI. I'm assuming their new stuff isn't well-received, because like I said, the amp I got from them (It was their first or second year in producing car audio amps, in fact) has been flawless.

Thanks!

 

[whtxblazer02 10+ year member]

Yet, that **** RF amp is barely 2 years old and it's already dead. That demonstrates some crappy product quality.

How can you say that when you don't even know what is wrong???

Sounds like user error to me......

 

[c_hayhurst 10+ year member]

How can you say that when you don't even know what is wrong???
Sounds like user error to me......

Because when it doesn't power the sub and causes a burning smell when connected to a power source and makes a god-awful squealing/popping noise in the amp, it's safe to say it isn't working properly.

Even when it is wired exactly the same way it has been for the last 2 years when was been working.

Sheesh...Didn't you read the other posts in this thread?

 

[whtxblazer02 10+ year member]

Rockford Corporation offers a limited warranty on Rockford Fosgate products on the following terms:

Length of Warranty (U.S.A.)

• Standard Warrany - 2 Years

Maybe it is still under warranty.......