Subwoofers Cutting Out at High Volume - The Elusive Solution

[z3nor]

Need Bass... What you just pointed out made so much sense to me. If it's both, how could the wiring be loose or incorrect inside the box? It couldn't be the only issue. Each woofer has it's own terminal because when I built the box it made more sense to have 2 with regards to the brace.

That said, I will be checking/moving the ground to ensure it's perfect. Can anyone guide me on a way to check the ground with a DMM?

Thanks for everyone's help so far.

[z3nor]

UPDATE: It's always gotta be the simplest things.

Spent about 3 hours last night rolling around in the trunk and back seat of my car trying to find a proper ground for this amp. The first thing I will say is that the Mazda 6 must've been f%#$ glued together because I seriously only counted 2 bolts (per side) holding the frame! Using the DMM I tested some possibilities and finally settled on a spot about 10in below the original location. It was one of the afore-mentioned bolts. I reconnected the power and tested it. I believe it helped marginally, but the problem still persisted so I went back to the drawing board. I pulled the rear seat out, side panels, rear-deck, etc and couldn't find anything that would suffice due to the bolt size or location. I decided to call it a day and just reconnected it to the new ground I had located earlier.

Let's back up... I got this car in September of 2011. I got my first Fi Q and Hifonics amp in December of 2011. I immediately returned the Hifonics because the Q wasn't compatible with my intended 1 OHM setup. That is when I got the Alpine M2000 (Stable to 2 OHMs, like the Q). After I set everything up, the woofer played fine but this problem I've been having plagued it as well. I ended up sending the woofer to Fi for inspection in February. The tech from Fi called and said there was nothing wrong with it but I didn't believe him so we worked out a deal to trade my Q for an SSD and I'd pay for the 2nd. Those came in March and the problem didn't reappear until about June when I pumped up the amp (after breaking them in and building my new box). Thus, we are here now, almost 1 year later.

Why do I tell you this..? Because when I first installed my amp in Dec 2011 and ran the power wire, I followed the golden rule: When working with electrical, always disconnect the battery. When I was finished, I tightened my battery terminal enough that it was snug, but had just enough give so you could pull if off without tools.

Well in my fury yesterday, I tightened the shit out of it... Rather, both of them. Guess what...? Problem Solved. Blasted the music way beyond the threshold it was going before and they kept playing as if to laugh at my incompetence. They still cut off at excessively high volume but I would attribute that to over-excursion/clipping. I've only had it do this playing "On My Level" by Wiz Khalifa. And yes, finally, my windshield is flexing.

So one final question for you brilliant audio minds: Would my amp benefit from additional "upgrades" such as the Big-3 or a different battery? Can the woofers take more power than they're receiving? I ask because I've heard the stock electrical only truly delivers up to 1000 Watts. Any recommendations?

Thank you to everybody that has chimed in and ultimately driven me to figure this problem out. I would not have been able to do it were it not for the workflow we created. I really do appreciate everyone's help and hope this thread leads to everyone checking there battery terminal(s). Thanks again everybody.

[Kyle Holliday]

My subs are doing the same thing . I went over everthing to come up with no soultion .,so i went to my local autoparts store to find out my stock alternaror wich is 70amps is only putting out 30amps. I an changing it to day . Hopefully this and the big 3 im doing when i put alt in,will fix my subs cutting out past like volume 12 of 60.,this seem accurate for a fix to this,problem to u guys. I will chime back with my results

[Bump4life]

well after reading your comment about dropping to 11.3 volts. THAT IS a problem.

I bet when you were cranking it up even more that that drops even lower into the 10s and posibly 9s which is why your amp shuts off. or subs cut out or whatever.

I suggest you get wire upgrades, do the big 3 and add a secondary battery in the back. a true 2000 rms which that amp will do can not be run with stock electrical.

also i suggest grounding your amp to the strut tower. once you get a secondary battery, ground battery to strut tower then groun amp to battery. use 1/0 OFC from sky high wire or knukonceptz. or a 2/0 or larger welding cable.