Dual-brand Amp Protect Mode? Help!

 

New member
Username: Rrlucas

Hancock, MI

Post Number: 1
Registered: Mar-11
Hello, new to the group.

I'm not sure what is going on with my system. My previous amp (Alpine) seemed to stop working or something last year (power light still came on, but it never changed colors, and sound stopped coming out). I just replaced it with a Dual-brand XPE2700 amp. To ensure a good connection, I went and ground-down all of my grounds so they were on bare metal on my chassis, and I have the amp wires connected directly to the battery (both ground and positive .... previously I just had the positive connected to the battery and ground to the chassis).

The amp powers on and I can feel and hear the sub working up until a certain volume, then it goes into protect mode. This is a very low volume. I've tried messing with the gain and all of my stereo's bass & sub settings, and it still does it.

This is a stereo (bridgeable) amp that I have bridged for a single sub. The amp states, when bridged, it can support no-less than 4 ohms (i.e. not 2 ohms). I checked, and my current speaker (600 watt 12" Pioneer) is 4 ohms. It should work... but it's not.

Considering it appears to work at a low volume, but not at a high volume, does that mean my speaker might be bad? I have two other identical speakers I could test it with, but it's a PITA to replace the sub in the box. Would this make sense for a bad speaker to draw less than 4 ohms, causing the "protect mode" red light to come on?

I'm wondering if this is why my last amp didn't work as well (maybe it's still good?), if the speaker is bad.

All wires are sufficient for this application. I believe the amp recommends 10 gage wire, and I have 8 gage wire throughout, and have it grounded twice (battery and chassis). Speaker wires are sufficient, as are RCA's (came in a 600-watt amp wiring kit, this and previous amps were 400W and less). I do only have a 20 amp fuse in one of them, but it seems if that was a problem it would simply blow the fuse (as it has in the past). It's all I had on hand, I plan to upgrade it to at least 30 amp fuse later (that is what the amp fuse is).

I'm not trying to have a "bumping" system... I just enjoy bass, which my current interior speakers can only provide at a high-volume... so I added a sub to provide bass at lower-volumes.

I plan on getting back to this on Thursday, so hopefully I could get some responses by then.

Thanks, I appreciate it!

Link to my amp: http://www.dualav.com/mobileaudio/xpe.php (XPE2700 version)

And yes, I know this is a low-quality amp ... I don't really care, as it's cheap and I don't often "push" it hard. It does the job.
 

New member
Username: Rrlucas

Hancock, MI

Post Number: 2
Registered: Mar-11
Oh... and the sub is 150W rms (and 4ohms) ... which is exactly what the amp says it outputs at 4 ohms bridged. Don't know how much that matters.

The amp manual says that in stereo mode (nonbridged), it cannot take a speaker load less than 2 ohms. Could I switch the bridging switch to stereo mode with the sub speaker wires still in a bridged configuration and not have any problems?

My previous amps were all Mono, and I guess that was an oversight when I bought this stereo (bridgeable) amp, not realizing it should have been mono.
Jump to: Home Audio Forum | Home Video Forum | Home Theater Forum | Car Audio Forum