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Ahh cool. I learned something today.

"When you say you used a voltmeter to set the gains, what do you mean? Like, what did you do?"

I had to assume how much power this amplifier put out (I know, very rough guess considering the "quality" of the amp). P= V^2/R, so to put out 200W RMS on a 4 ohm load, the channel would have to put out around 28.25 volts to achieve it. Since the amp is crap, I set it to put out 25V, which is closer to 150W. I keep a CD with 0db reference tones for setting such things. Basically, I just assumed a nominal impedance of 4 ohms and I assumed the amp would put out 150W on a channel. Rough guessing, not exact, but I'm not really that anal about setting somebody else's gains.

I went to the trouble of using a meter to set the gains, guess at the power, and set up the amplifier, with the guy watching me and me explaining this to him at the same time. Then shortly after, the guy cranks everything full tilt not knowing anything about the amp, pisses me off.

When you say you used a voltmeter to set the gains, what do you mean? Like, what did you do?

"Nope, it can for sure blow that sub, and amp in the process. If he turns up the gain and starts sending clipping signals to that subwoofer, he is going to blow the subwoofer and the amplifier."

Won't blow that sub. Not in this application. The only thing that kills a speaker is either heat or overexcursion. Which requires overpowering on both accounts. Clipping gets blown out of proportion, it isn't the clipping that damages a speaker, it's the resultant average power increase. Distortion doesn't have any relevance to the issue. Even when clipping, the maximum power increase is double power. A voice coil isn't going to start rocking and moving in crazy directions just because an amplifier is distorting. Harmonic distortion will increase greatly, but it is harmless to a sub. Even if that amplifier doubled power from a square wave, it would still only put out 240W RMS, which I guarantee wouldn't fry that sub. If a 500W RMS sub blows from a fully clipped 120W RMS amplifier, it's because the sub isn't built worth a damn to start with.

thats a really awsome sub i had one in my mustang when i first got it and it is the best sounding sub eclipse made. you should offer to buy it back and he should get a bostwick or what ever that amp was.

well I was just at my shop looking at a sweetass dashboard all vinyled up and no where to go when low and behold, a fine ass kia rio comes in, with a dual nob jensen HU, two Legacy 1200w 10's (w0w) and get this....one kenwood ka-524..something like 30wx2 with no lowpass filter on it. This kid pays 95 bucks to get 8g wire run to the rear, a premade box and these POS subs in it, with the whopping 60w going into 2 10's FULL RANGE! I had to stay there just so I could hear it. WOW is all I can say..and that my friends, isn't good.

So Jonathan my friend, it could be worse.

Justin from Detroit wrote:Nope, it can for sure blow that sub, and amp in the process. If he turns up the gain and starts sending clipping signals to that subwoofer, he is going to blow the subwoofer and the amplifier.

agreed.......if you think that amp is getting hot and distorting what do you think is happening to his voice coils?

Nope, it can for sure blow that sub, and amp in the process. If he turns up the gain and starts sending clipping signals to that subwoofer, he is going to blow the subwoofer and the amplifier.

He doesn't have internet. I've tried every way I can to educate him on the hows and whys, but he's just one of those guys that doesn't care to know. Oh well. That amp couldn't put out enough power to do any harm to that Aluminum, though, I'm safe from the "why did the sub blow" questions.

maybe direct him here to the site so we can tell him