3.5 cu.ft. for a kicker l7 12" too much?
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=53703
Printed Date: May 20, 2024 at 6:40 PM
Topic: 3.5 cu.ft. for a kicker l7 12" too much?
Posted By: glowstickninja
Subject: 3.5 cu.ft. for a kicker l7 12" too much?
Date Posted: April 11, 2005 at 11:22 AM
OK i am building a box over the next couple days, i have ran a bass box pro run of a kicker l7 box for 12" sub and had it tuned to 38hz, just wondering if 3.5 cu.ft. of inside volume going to sound bad? I mostly listen to rap, so i want something that hits hard and lowwww. oh and KX1200.1 going into just the one dual 2 ohm sub.
Replies:
Posted By: ogkw
Date Posted: April 11, 2005 at 1:57 PM
If you are talking about a L7 in a sealed enclosure 2.0 is the max recommended by kicker. If it is ported 3.25 is the max, which is close enouth to 3.5. If this doesn't help go to www.kicker.com, they also have technicians that will talk to you on the phone if you call the company. I have never owned anything but a kicker speaker and know their quality. ------------- 40oz. and a mule
Posted By: stevdart
Date Posted: April 11, 2005 at 10:34 PM
With those subs, the larger you make the box the flatter the response will be. Have at it at 3.5 ft^3. And contrary to what was said above, I just looked at the L7 manual a couple days ago and I believe they said you could go 6 cu. ft if you wanted in a sealed enclosure for the best SQ. IMO, you could double that 3.5 and be good for ONE driver!
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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.
Posted By: glowstickninja
Date Posted: April 12, 2005 at 10:37 AM
The box is going to be vented, soi was looking on kickers website and found some technical manuals with box designs. The biggest one they have for an L7 12 only says it can handle 750w which is very weird when the max rms wattage on the sub is 1500w. The box is 3.25 ft^3, which undoubtedly will sound great, but ill it be too much for the driver if i put a full 1200w into it?
Posted By: kfr01
Date Posted: April 12, 2005 at 1:39 PM
Sealed or ported, the larger the box, generally the lower the power handling. Porting a sub also reduces power handling.
Do not feed it the full 1200w.
This is the price you pay for the increased efficiency in a ported box.
I wouldn't let the halving of power handling bother you. Efficiency helps your system all the time, power handling only helps when you're cranking the volume knob with reckless abandon.
That said, if you know you can't help it and you love to show off and you're going to frequently abuse your system with a 1200w amplifier, go with a small sealed box and high power handling. In my experience people don't buy L7s for sq.
Also, 38hz is too high a tuning frequency if you want it to hit "LOW." I can almost hear you constantly unloading that thing from here.
I highly recommend going small sealed first.
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New Project: 2003 Pathfinder
Posted By: stevdart
Date Posted: April 12, 2005 at 10:21 PM
L7's have a high Q at almost 1.0 and have a definite peaked response at about 50 Hz. A smaller box like about 2.25 ft, which is about what you would normally use in a car as a "big" box, would peak at about 70 Hz. There's not a whole lot you can do about this fact. This sub is designed for a sealed enclosure with a very low EBP in the 40's. Use them for the SPL sub that they are and slam the power to them until you just can't take it no more.
Posted By: glowstickninja
Date Posted: April 12, 2005 at 10:30 PM
Yaada that is what i am looking for is SPL i dont really care how clean they are cuz i am listening to mostly rap and hip hop. Now another qusetion arises, is that really true what he said about the gain just keep it low? cuz the amp is still putting out 1200 rms no matter what right? that could be very dangerous to the sub. but of course that is at 1 ohm i could run it at 4 ohms until i get the nes sub, that would be 300X1 (about 150 to each voice coil) the max rms to each coil is 350, so that would still thump hard right? also after i get another sub to match i could wire them in parrallel to represeent 2 ohm load on the amp and be running 2 at 300 watts each or 600X1 off the amp.
Posted By: stevdart
Date Posted: April 12, 2005 at 10:49 PM
cuz the amp is still putting out 1200 rms no matter what right? No. If you set the gain on an amp to a lower setting than what would properly match the input voltage, the amp will respond by putting out a disproportionate amount of power into the load. It's the reverse of "cranking" a gain too high, in that the power is disproportionate to the input voltage in either case. It can be proportionally too much, or it can be too little. You want to err on the "too little" side. Just set the gains by tweaking a hair at a time until you get that tell-tale distortion, then back it off. That's telling you that the subwoofer has had its fill and doesn't want that much power. It's really nothing scientific...just your normal gain setting procedure using the 'by ear' method.
Posted By: kfr01
Date Posted: April 12, 2005 at 10:55 PM
Hmm.. Stevdart... Yeah, I guess that would work, but you're recommending setting the gain based on excursion-related distortion rather than signal / amplifier distortion?
$10 that experiment eventually results in one damaged woofer - probably not during the gain setting process, but $10 shortly thereafter during a rap show off session.
:-)
I still think the small sealed box or running at 4 ohm are the best solutions here.
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New Project: 2003 Pathfinder
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