amp sub match questions

[tranced 10+ year member]

I recently ordered a MB-Quart-ONX1.1500D(1000rms@2ohm) to power my 4 ohm DVC Audiobahn aw1006t(900RMS) . Seems like a great match for each other @ 2ohms. anyways my friend wanted to try out my sub with his new amp after work today so what the hell why not. he has a Alpine MRP-M500 amp. This thing is only rated at 500RMS @ 2 ohms. we hook it up and my sub sounds great. after like 3 minutes of testing a bass mechanix cd, i began to smell the familiar voice coil smell. i let it hit for another minute to see if it went away but it didnt. I felt the cone after we shut it off and man that thing was hot. so my question is what gives? this sub is rated for double what that amp puts out and it was well on its way to killing my sub in 10 minutes flat? Granted i know that audiobahn isnt the greatest, but this particular line of them were supposed to be tough as nails. Is my new amp going to be the death of this sub?

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[goingdef 10+ year member]

what gives is even though it sounded loud and great you where clipping it heavily trying to get it to move with such a small amount of power, you may want to pull the woofer and look at the coil and see if you burned it.

 

[tranced 10+ year member]

I will check of course tommorrow during the day. but heres my thing, i ran a lanzer on that sub that was supposedly rated at 900rms, later found that it wasnt even close to that. 341 i believe the math came out to. so technically its been clipped before. it never warmed up the sub at all

 

[quackhead 10+ year member]

what do you mean "technically, it's been clipped before" ?....explain.

 

[tranced 10+ year member]

just took it apart. voice coils still look shiny and new, pressed down the sub got a slight scratch at the bottom. i mean its been clipped before because that lanzar was underpowering it much more that this alpine was. if you go back to the conversation we had quack im sure youll remember. http://www.caraudio.com/forums/wiring-electrical-installation-help/550942-installation-help-plz.html#post8086321

*edit scratchin only came when pressing down slightly off center of the cone

 

[LosIsATool 5,000+ posts]

just took it apart. voice coils still look shiny and new, pressed down the sub got a slight scratch at the bottom. i mean its been clipped before because that lanzar was underpowering it much more that this alpine was. if you go back to the conversation we had quack im sure youll remember. http://www.caraudio.com/forums/wiring-electrical-installation-help/550942-installation-help-plz.html#post8086321

Underpowering WILL NOT hurt the sub. What do you think happens when you turn the volume down? What happened was with your buddies amp, he is just as bad as you and the gain and or bass boost is cranked. Gain is there to match your headunits pre out voltage not a power knob. The sub is also very overated. If you have scrathy coil then its falling apart, unless you pushed it down not completly straight

 

[tranced 10+ year member]

he never changed the gain. its still set below halfway on his amp. albiet his headunit is new, but hes been screwing around with subs since the early 90's so i figured he had it set properly. apparently not. his kicker 12 never gets warm tho and that thing pounds.

 

[quackhead 10+ year member]

I know you were vastly underpowering it, but that has nothing to do with clipping. you can drive it with 90 watts from now on and it won't hurt a thing. Clipping happens when you set the gain too high and the amp clips, or too low and clip the HU signal...or let the voltage supplying the amp fall to a point that the amp clips the signal. As long as the components are properly gain matched and you do not exceed max volume (the reference point you use to set the gain), or fail to supply proper voltage to the amp, there should be minimal clipping (if any).

 

[quackhead 10+ year member]

Underpowering WILL NOT hurt the sub. What do you think happens when you turn the volume down? What happened was with your buddies amp, he is just as bad as you and the gain and or bass boost is cranked. Gain is there to match your headunits pre out voltage not a power knob. The sub is also very overated. If you have scrathy coil then its falling apart, unless you pushed it down not completly straight

This will cause clipping too...and some songs are clipped, and a combination of these things combined will make matters worse.

 

[tranced 10+ year member]

or let the voltage supplying the amp fall to a point that the amp clips the signal.

i thought this would result in the same thing as underpowering. still learning bro. i think i got away with this one guys. guess it pays to have just a little luck once in a while

 

[quackhead 10+ year member]

i thought this would result in the same thing as underpowering. still learning bro. i think i got away with this one guys. guess it pays to have just a little luck once in a while

I'm with ya, bro....the amp has a rated voltage range where it is designed to operate. If the electrical is good and the amp is not wired outside of it's recommended nominal loads, the amp should amplify the signal without clipping due to electrical. But just like we discovered when talking about power output with different amps, this is another area where amp ratings can be deceiving too. As far as your buddy's amp gain being set "a little under Half"...this too means nothing. If your source (HU) only provides .5v max through the line inputs, then the gain may be turned almost all the way up...if the source voltage maxes out at 7 volts, then the gain may be almost all the way down...source voltage varies by head units and gain ranges varies by amps...not all are the same.

 

[imp4pdabest 10+ year member]

A whole lot of clipping.

 

[tranced 10+ year member]

man if i would of known half this stuff before i started lol. well anyways it looks like his HU has a 2.5v preamp out put (jvc kw-r500). and its really hard to gauge the gain settings lol. it only has 1 reference point at .5v slightly at 1 o'clock lol. they should label these better than they do. Anyways so what i take from all this is this happened bc the gain on his amp was set or calibrated for a specific volume for his 12, and because he had to turn it up more(he had it crankin near max volume) for my 10, it sent clipped signals and nearly toasted sub. lesson learned

*edit im looking into buying this HU also. this alpine has such a terrible eq

 

[quackhead 10+ year member]

lol...i see. Maybe you was burning the dust out of that sub, since you was powering it with a couple of hundred watts (maybe) before...lol. There is not even a minimal gain number to reference with this amp. But seriously, if you smelled coil, you were either grossly overpowering or clipping it.

 

[quackhead 10+ year member]

I take it the coils were wired correctly?