Had a weird occurance the other night in the shop. Stayed late in the bay last night till about 10pm working on this real nice Mustang GT. We did a nice flip-out, all new interiors, 4-channel, 2 batteries, big 3, 1.5F cap, and 2 12" Kicker CVR's with a ZX1500.1. Anyways onto the problem. Get the install all done, ready to go home, just gotta finish tuning. Set all the interiors, they sound great, get the o-scope out, measure gains on headunit, match gains on sub amp, everythings goin great. Put a cd in crank it up, first low bass note, amp shuts completely off. No protection, nothing. Second later comes back on.... next real low bass note, shuts off again. Alright so troubleshooting time.
Check sub impedence at amp, fluctautes between 1.9-2.0 Ohms. K that's fine, checked ground and it read 4 ohms! Ok so we think we found the problem, change ground, test again, reads .01Ohms. Can't get much better than that. K so we try again... Same thing!! Whip out the volt meter and set a min. hold on it. Lowest reading while running is 13.9V. Perfectly within reason.
So now I'm convinced it's the amp. Maybe a bad power supply or something. So we swapped it out with a SX1250.1 and it hammers... no problems at all. Despite the fact that I hate the SX amps for anything but SQ and that the 1250 is a 1 ohm stable amp and we're set-up for 2 ohms, but it still sounds just fine.

So now I'm thoroughly convinced it's the amp. Just looking to see if everyone else agrees. The only other thing I can think of is the new ZX amps possibly have a clipping protection of some sorts, but o-scope showed no clipping, plus I asked Kicker and nope, doesn't have such a thing.

The SX1250.1 is my other installers personal amp, so we have to send this kids 1500 out if it's bad. So anyone else have any other ideas before I send it out, or does the verdict remain it's just a POS amp?

 

Well....if you switched it out and the other worked fine, I would have to agree its probably something with the amp.......No protectin lights come on huh????

 

Nope not a thing. Protection light comes one when it powers back up, but it does that normally, then turns to green. I've never seen one that the lights go completely out, usually they go into protection, but they don't just shut completely off....? Oh and BTW, I got a SX700.4 sitting next to me if you're looking for one Habeba.

 

I really wanna stay with a 2 channel....im looking at an arc 2500 xxk But ya with the amp.......ummm jst the 1500 shuts off not the 4 channel also correct?

 

Alright, figured I'd ask lol. We never hooked up the 4-channel. Just the 1250.1. Never had any problems with the 4-channel. The owner of the car just decided to tell us that the amp started to do the same thing in his old vehicle. So now I'm 100% sure it's the amp.