sub / amp problem ??
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sub / amp problem ??
hey guys, i posted a week or two ago about my sub.
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.
Now, i got 2 10" subs, and installed it today. 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.
Is there something wrong with the amp? any ideas?
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.
Now, i got 2 10" subs, and installed it today. 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.
Is there something wrong with the amp? any ideas?
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I hooked up a voltmeter...
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.
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.
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more info...
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?
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?
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Info?
What kind of subs are they? Are your subs dual voice coil? What kind of box are the subs in, ported, sealed, or banpass? What kind of amp do you have, exactly? What is the condition of the ground that you are using? Where do you have it grounded? Are you blowing fuses too?.....get back to me with the answers.
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sorry for the delay, was out of town...
The subs are 10" JBL GT100. 4ohm single vc, 250w rms, 1000w pk. I have them hooked up in parallel in a sealed box.
The amp is an alpine mrp m350. 200w rms @ 4ohm, 350w @ 2ohm, 700w pk. The ground is connected to the bottom of the trunck (car's metal), so the ground is pretty good.
It doesnt look like im blowing any fuses either.
The amp is an alpine mrp m350. 200w rms @ 4ohm, 350w @ 2ohm, 700w pk. The ground is connected to the bottom of the trunck (car's metal), so the ground is pretty good.
It doesnt look like im blowing any fuses either.
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after reading your threads, i need some more information
when the subs stop working, is the amp going into protect mode?
one thing you need to do right away is invert the phase on one sub so they are both in phase. if they are cancelling each other out, you may just be running the amp way too hard because u need the gains all the way up to hear any sound.
you could be clipping the amp and blowing your subs.
just possibilites. looks like everything is hooked up correctly. just invert the phase of one sub and see if that helps.
one thing you need to do right away is invert the phase on one sub so they are both in phase. if they are cancelling each other out, you may just be running the amp way too hard because u need the gains all the way up to hear any sound.
you could be clipping the amp and blowing your subs.
just possibilites. looks like everything is hooked up correctly. just invert the phase of one sub and see if that helps.
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I tried that, not much has changed... i think...
that the reason one sub was moving in, and the other out, is because only one of the subs was actually being in use. Since the box is sealed, i think since one is going in, the other automatically will go out because of the flow of air in the box. Thats what i suspect is happening.
Unfortunately, i have no clue if the amp is going into protection mode. Im not sure how to tell.
Unfortunately, i have no clue if the amp is going into protection mode. Im not sure how to tell.