WTF?! Please help me before i blow everything.

[i like guns 10+ year member]

I have 2 audiobahn 450 watt subs, 4ohm svc. Theyre hooked up in parallel to a kenwood KAC-9125D amp. Theres no gain or anything on the amp except for a voltage imput dial. I turned that to 2 since thats my HU preamp runs at and measured the voltage and it only said somewhere around 10 volts. So the bas boost was off and i turned it all the way to max and only was getting in the high 20s on my DMM, then the subs just stopped moving. they didnt sound distorted but then again im not too expierienced. Is that the gain? should i leave it at 2? are my subs ok? they were warm to the touch when they stopped playing.

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[XaznKewLguyX 10+ year member]

just blow them and get new subs //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[mazdakid 5,000+ posts]

have you tried taking the piece off the top of the amp thats held on by allen bolts for the gains?

 

[i like guns 10+ year member]

yes, theres no official gains but instead theres a voltage imput, which sorta acts like gains. i turned this all the way to the max line (.2 volts) for the pre amp even though mine is 2 bevcause i still wasnt getting the voltage output that my subs need (42.4 volts). So now the amp turns on and the subs dont play. I want to know if they are blown. Ill check the fuses on the amp tomorrow.

edit: If the voltage preamp dial isnt the gain, then how do you adjuest gain? and why did my subs fail when the voltage coming out of the sub was about 15 volts under the recommended? sqrt(900 x 2) = 43.4

 

[theCybe 5,000+ posts]

I think you have some misconceptions; Your subs don't 'need' 42 volts, and even if you get 42 volts out of the amp on your DMM, they might not be clean/unclipped.

sqrt[900*2] = volts you need to produce 900 watts into the 2 ohm load; HOWEVER, if the amp is rated for less than 900 WRMS @ 2 ohms, you'll be feeding your subs dirty power by the time you get up to the desired voltage.

 

[i like guns 10+ year member]

^ the amp is rated for 900 wrms at 2 ohms. Still, im glad they didnt blow, but im nervous as to why they were warm.

anyways... the battery terminal fuse was blown. Its only 30 amps. so thats why, now it works. im happy again. except the subs really arent that loud. i rather have the fuse blow at too high imput levels though.

 

[InhumanAcura 5,000+ posts]

lol @ the title

 

[i like guns 10+ year member]

I only need to know the answer to this question?: is it ok for the subs to be warm or does that mean im pushing them too hard.

 

[SAG3 5,000+ posts]

that is the gain and dont push the subs uber hard unless you do want to blow um.

 

[theCybe 5,000+ posts]

They shouldn't be warm, you might be clipping them.

 

[qtipextra 5,000+ posts]

Anytime you run subs for an extended period of time, or push them hard, your going to have heat.

Subs are, to your electrical system, just another resistor. How does a resistor resist power? It takes the exess power and produces HEAT instead. Thats all a sub is doing, but we use the vc's magnetic power to produce sound.

It seems like when you were adjusting, you were clipping your amp, and sending high amounts of power to your subs, and in turn, that creates heat, which is shy they would be warm to the touch.

U always need to be VERY cautious when adjusting gain (or anything that affects power on your amp) when your subs are hooked up.

BTW: Sorry for all mis-spellings, I seem to be out of my element on spelling today.

 

[CBFryman2 5,000+ posts]

was your HU turned up to around 3/4 volume?