Electrical Question ?

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Big Mack
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Postby Big Mack » Sat Nov 06, 1999 4:32 pm

You're drawing 125 amps through 4 ga? That's not a wise choice. 4 ga is not rated for anything more than 120, no matter the length. Granted, it's not that much of an overload, but it isn't wise to even be at the maximum, much less go beyond it. I would upgrade to a larger cable on that. As for the rest, you still need to check everything out, T, and let us know what's the story.
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jlaine
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Postby jlaine » Sat Nov 06, 1999 5:45 pm

Yeah, i know I am cutting it close, but that figure is one that will never occur in reality. I used a function generator set at 25 Hz and ran all of the channels of all of the amps at minimum impedance, which is also not going to happen. The Earthquake is at 3 ohms, and my Infinity's are at 4, so that figure is never even approached, in reality, with a good burst, the cable has never seen more than 80 amps max.
TBass

Postby TBass » Sat Nov 06, 1999 5:53 pm

Thanks guys, but the sub is a SVC 6ohm, and RF claims that there amps are stable at 2.66 ohms, and also about the cable, that's the size RF recommends, I have 2 cables going to my trunk, one 8awg for the RF 240.4, and one 4awg to the RF power 500.2, yeah I will hook up a relay soon, and also change my ground. and get a power alternator, also I heard it's a good idea to change the wire from the alternator to the battery, which I should do that also, I upgraded the ground wire from the battery to the chasis too. the amp doesn't get hot, it get's warm, but not really hot like before. everything seems to be working fine now, but I will do all those changes too. Thanks again.
TBass

Postby TBass » Sat Nov 06, 1999 5:55 pm

Hey I just thought of something, I don't have gold power terminals, I'm still using that paper stock thing it is a must that I upgrade that? Or it can wait.
TBass

Postby TBass » Sat Nov 06, 1999 9:37 pm

Hey I just installed a remote relay, and the problem started again, so I lowered the bass volume on my head unit from 13 to 10, and it seems fine agian, the max on the bass volume is 14. But I know there is a problem somewhere, cause when I first installed the subs, I installed only 1 and had all my bass Eq, and gains up and it was rocking with only one sub. Next thing I'm doing is changing the ground back to the first spot I had it in.

T-Bass
TBass

Postby TBass » Tue Nov 09, 1999 4:09 pm

Ok, I think I know why my amp shuts off something, it's not the amp, but I think it's clipping cause of the sub. OK everyone says that a SVC 6ohm sub can sometimes drop to 1ohm, or 4ohms, my amp is rated at 1460 watts at 4ohms, and close to 1800 watts around 3ohm . so when the ohms drop on the sub. That amp is trying to give over 1500 watts to the sub. Is this true, and causes the sub to clip. that's why now I don't hear the upper bass tones, only the low ones hit.

T-Bass
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jlaine
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Postby jlaine » Tue Nov 09, 1999 5:19 pm

Unlikely, the change in the general resistance of a subwoofer should not effect the performance of your amp, unless there is something bad inside your sub. The amp is designed to handle the manufacturers specified resistance, so there should be no problem with using it in your current configuration. Since you were using the configuration before and had no problems I would say that there is something else prior to the sub. Yes the resistance could approach one ohm, but never in such a continous state as to shut down your amp. There could be a problem with the voice coil of your sub, but I doubt it. If you realy want to prove the resistance theory wrong, hook another sub up in series and see if your amp shuts down then. You say that you no longer hear the higher bass notes, have you adjusted them down or has the subs quit reproducing them after this problem started?? If I remember right (I am a little foggy on this) the resistance of a sub is lower at the lower frequencies, which would mean that your amp should shut down at the low bass, and handle fine in the upper range. Have you experimented with a different sub yet? You should try that, and also remove the eq and any other instruments that you have inbetween the head and the amp. The fact that your sub will not reproduce any sound at higher bass frequencies has me puzzled, perhaps there is something wrong with the sub, the voice coil could be shot, but I would try the other options first, since you have gone this far, take her the extra mile and get this nailed. I am afraid if it is let go you might have a bigger problem down the road... Take her one step at a time and keep us informed...
TBass

Postby TBass » Tue Nov 09, 1999 10:16 pm

Thanks alot man, you are so much help, I think the best thing to do now, is just wait, in 2 week my brand new sub is coming from Eclipse, so that's how I can tell, I'll hook up that other sub and see how it sounds, if it does the same thing, then it's not the sub, then I'll try to hook up both and see what happens. The reason why I'm saying about the ohms is if the sub produces a 3ohm load on the amp, then the amp is giving the sub close to 1800 watts, this makes me think that this is the reason why I had to lower my gains almost to 0. But I could be wrong. I will change my ground this weekend and let you know. I hear the upper bass, but it's not loud as the lower bass.

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