1 Sub great, both- Not so good?

[Micky7]

Hey I'm not sure what Ive done wrong, but I can't seem to get my subs to go properly.

I have an Alpine MRP-M350 running 2 Alpine Type-E 10's.

This is what I figure should happen. I run the subs in parallel (2 SVC 4Ohm) to get 350 watts per sub outa the amp, @ 2ohms to the amp.

However what really happens is that the subs sound terrible, almost like they were blown, at very low volume (gain, levels etc etc all tested). When I run only 1 sub, it sounds great (4ohm @ the amp, 200watts right?). they both work fine, only alone. They are together in a sealed box.

What might be wrong here? How can I help them live together??

Just in case... I have a celica, and I noticed the alt. only puts out 70amps, is this of any concern? I have a Pioneer HU and 4 alpine type s speakers, everything is fine with them. My power wire/ground wire is 4 gauge, the sub wire is a bit smaller, 12 I think. The ground is in the trunk, I think there might be another ground from the car entierly too close to it, I'll try moving the ground as soon as I have a warm garage to work in.

Any suggestions appreciated! If you want to know anything else, ask!

Thanks

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[adam71 5,000+ posts]

If your ground was your problem then it would do it all the time...NOT just when you have both subs hooked up. First of all, is your amp 2 ohm stable? Second of all are you sure you have them wired correctly? Just a couple of things to check out.

Adam

 

[Micky7]

The amp should do this quite well, specs say :

MAX Power (at 14.4V,EIAJ)

Brigded into 2 ohms : 700W x 1

RMS Power (at 14.4V,20Hz-20kHz)

Per channel into 2 ohms : 350W x 1 (0.3%)

Per channel into 4 ohms : 200W x 1 (0.08%)

So the way I wired it was AMP- to SUB1-/SUB2- and AMP+ to SUB1+/SUB2+

Correct Parallel? right?

I suppose the ground is fine if the subs work properly 1 at a time.

If there is some simple spultion to this that would be great!

If not I considerd grabbin' another M350 for the other one.... if I could power both of them.

 

[adam71 5,000+ posts]

I'll be totally honest with you..........I'm stumped.

Adam //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

 

[cyberbob25 10+ year member]

Is it possible that you are wiring them out of phase? If the polarity is reversed on one of the subs, then they will be moving in opposite directions, and cancelling each other out.

 

[Micky7]

Ok, I'd like to pass the blame along to my 'lemmie dooo it' friend who belives he is the universal handyman extrodinaire! The subs being wired out of phase striked me as exactly what it sounded like... and obviously had checked and checked again the wiring... On the outside of the box. !!! I pulled the back off in the shop this afternoon at work, and traced the connections from the posts to the coil... low and behold one of e' is f'n backwards.

How do I account for this? my friend and self proclaimed Master Electricitan did this while I was running wires in the car. Then sealed the box.

YADAYADAYADYAA

Anyways ---> Problem solved, Subs sound great, I have nothing more to complain about, except having to drive an extra 20 minuest tonight to deliver a well placed slap across the head. Thanks for your time!