Bad Black Si

Hey guys, hopefully someone here can help me out with my setup.

Basically, it would work, and after 10min or so, just fade away. After pressing on the sub with my finger, i could see it working, but not under normal conditions. I was told the sub is no good. Maybe a fractured voice coil. So, since i wanted new subs anyways, i got some.

Now, i got 2 10" subs, and installed it yesterday. For about 5-10 minutes again, it was ok, then all of a sudden, nothing, and pressing on the subs wouldnt help at all, they just stopped working.

After a while, i would turn the stereo on a bit, and i could hear the subs a little, but not loud enough, and they became silent soon after.

This morning, after i turned on the car, it worked for a couple minutes, then stopped again.


Is there something wrong with the amp? any ideas?

imported_hdave

seems like it has to be your amp

what kind of amp is it?

Bad Black Si

Its an alpine MRP M350
http://www.2001audiovideo.com/car_01/amps/MRPM350.html


I just took a voltmeter to the system.
The voltage from the batter is good, approx 14V.

The voltage coming from the amp is approx 0-1.5V RMS AC. When the sub level is zero, zero current, when i turn the sub volum to max, its 1.5V approx. Is this too little? This is the voltage measured from the amp, without a load seen.

since i have 1 10s, it should see a 2ohm load. When i measure the voltage on this load, its about .7,.8V RMS AC at max sub volume (but the sub not working).

Bad Black Si

My friend at work has a sub setup in his car.

His one 10" worked ok in my car, it didnt just fade away.
My 10s, when put in his car, took a while before they actually started making some sound, and when it did, we noticed that the subs were out of phase (one goes in, the other out).

I wired them both in parallel. What could i have done wrong to cause this?

imported_hdave

wiring.

swap the (+) and (-) on one of the subs

doesnt matter which as logn as both subs are gonig the same way

Bad Black Si

Would that cause the sub to stop working though, or cause the amp to kind of shut down like it was?

Gunmetalef

is it getting hot .. going in protection mode?

Bad Black Si

I tried switching the terminals on one of the subs, and it made even less sound.

The amp doesnt really get hot at all. I dont think its going into thermal shutdown.

After carefully looking at the sub wiring, i can say that they are in fact hooked up in parallel. I have no clue what else it can be.

imported_hdave

hmm...

try hooknig them up in series.. they will get less power, but try it and see how it sound and what happens after u do that.

which subs are they?

Bad Black Si

They are JBL GT100 subs.
10", 250W RMS, 1000W peak, 4ohm vc


Ill try em in series now