Blk03GS430

Hi guys, I just replaced my 10" ML factory subwoofer with the Kicker 10c104 10" 4 Ohnm subwoofer http://www.crutchfield.com/p_20610C1...0c104&skipvs=T that is rated for 150 watts rms. Im using the Kenwood KAC-1502S 2 channel amp http://www.crutchfield.com/p_113KAC1...2S.html?tp=115 that is bridged to 150 watts rms at 4 ohms. It sounds ok as far as I can tell but the part I am unsure about and need your advice on are the following:

I spoke to Kicker tech support & they advised me that the Kicker 10c104 subwoofer can be used in a free air applications but it is not a true free air subwoofer and the power from the amp to the subwoofer needs to be cut in 1/2 in free air applications because Im not using a box & it may bottom out the subwoofer/damage it. So they want me to use only 75 watts rms from amp to the subwoofer and the only way to do it with the amp is to use their 8ohm version of the subwoofer http://www.crutchfield.com/p_20610C1...0c108&skipvs=T that is rated also for 150 watts rms but the 8ohm subwoofer will automatically cut the 150rms power to 1/2 which is 75 rms.

Im afraid that 75 rms power from my amp to the subwoofer may not be strong or powerful enough to make the subwoofer sound good. Can you audio gurus tell me if I should stay with the 4ohmn sub and have the amp push 150 watts rms straight to the subwoofer or go with the 8ohmn subwoofer that will auto cut the power in 1/2 to 75 watts rms? The most important part for me is to get a good amount of bass coming from the sub and it has a strong punch. Can you guys give me the positvie and negatives of each setup.

Thanks for your time and help.

Robert_J

First the RMS rating is almost always useless and this is exactly why. The RMS rating is how much power the sub can take before things start to melt. They never use a frequency that will push the sub to its full excursion. In your case since there is no enclosure, it takes much less power to push sub to its mechanical limits and no where close to its thermal limits.

That's one solution. Another solution is to turn the gains down on on the amp so you never push the driver past its maximum excursion limits. Another solution is to keep the volume turned down.

If your sub doesn't sound good, it's probably because it is a Kicker. They aren't known for sound quality. But then again, Deon Bearden is now the engineering manager there and he's in my top 3 list of subwoofer engineers.

The Kicker has 9.6mm of one-way excursion. For 1 penny more, you can get an Elemental Designs 10" driver with 15.6mm of one-way excursion - http://www.edesignaudio.com/product_...products_id=30 that also works well in infinite baffle installations.

IB installations are not known for either their output nor their "punch". They lean towards sound quality installations where bass accuracy is important. If you want output and punch, build an AutoTuba - http://www.billfitzmaurice.com/autotuba.html . As you can see voltage meter on the video, this design is extremely efficient - http://www.youtube.com/watch?v=WE6BOd3bCWk .

Blk03GS430

Thanks for the quick and helpful response Robert J. I actually got the Subwoofer on sale for less than $50. The whole setup with the amp is actually cheaper than buying a used ML paper subwoofer.

I understand the explanation of the watts rms but I was just wondering if the subwoofer sound will be decent enough at 75 watts rms from amp to sub? Im curious to find out how much of a sound difference will it be from the 150 watts rms I am currently pushing to the 4 ohm sub compare to 75 watts rms to the 8ohm sub.

Whats is the worst that can happen if I continue to use 150 watts rms from my amp to current sub at a moderate to sometimes high volume?

Thanks in advance for your time and help.

kGhost

Any update on this Blk03GS430? I'm thinking about using the EXACT SAME SETUP and wanted to know what you ended up doing...

Thanks in advance.
KG

irishcharm

iTrader: (1)

Harsh. and false....anyway.

ohm is the measure of resistance. that being said i personally would go with the 4ohm setup. also among cost factors for amps/subs/future wiring and upgrades and personal preferences.

the op was months ago too lol.

Shibumi1

i'd suggest an amp with a subsonic filter to control how low of a frequency the sub will play..to keep it from bottoming out... and maybe look at the pioneer shallow mount sub.. it has a super stiff suspension


http://www.pioneerusa.com/PUSA/Car/S...TS-SW2501S2|S4