In their operating manuel, Kicker suggests using a subsonic filter in the interest of producing the most output from their subs. They go so far as to suggest that their s12l7 will operate at 750 watts rms in a ported enclosure with a subsonic filter and only at 400 watts rms in the same enclosure without the filter. Is this just a marketing ploy or is it really valid? Are these statistics also applicable to sealed enclosures? My deck only puts out frequencies from 20 - 20k Hz, if it doesn't play anything below 20 Hz then anything below 20 Hz shouldn't go to the sub right?

Thanks for your reply

Dale

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Music sounds better when it's loud.

in a ported box there is not much cone control below the tuning frequency of the box .......

so if you feed a box tuned to 30hz a 20hz signal it will usually flap around widly and loose it cause it has very little power handling below tuning

so if you put the l7 in a box ported to 30hz then you'd want a subsonic filter set just slightly below 30hz ........


I know your thinking but what about that low bass, most music has no bass that low anyways ........

I have the subsonic filter on my rubi 702 set to 30hz and I can turn it on and off and notice no change in music .......


if you go to soundstream's old website and download a manual for their amps it explains how the "hawkins bass control" works and how much excursion is wasted on subsonic frequencies [img]smile.gif[/img]

It is a good idea to use a subsonic on any woofer system. It saves amp power for frequencies you hear and makes life a little easier on the woofer.
They are not a necessity but if you have the option of picking one up or a piece of gear with a SSF in it then I would.

Everyone here is correct. ported boxes dont have the back pressure the same way a sealed box does. When the ub passes below its tuning frequency things get a little uncontollable. Lower frequencies around 20 hz can cause havoc in a ported box so we recommend that you filter them out. Depending on the sub, the type of box and your listen tastes/levels a subsonic filter can be a handy thing to have. why have the amp waste energy trying to play what you cant hear or what may damage your sub.

you should be fine uintil half an octave below the tuning freq.

[img]tongue.gif[/img]

that's a 20hz tone to a 12" Inhuman, box is tuned to around 40 hz.. 3,000 watts

don't worry the sub was already messed.. and it's time for a recone..

Good God. So is it fair for me to assume that my L7 in a sealed enclosure will be able to handle around 1000 watts without a subsonic filter (even though a filter is preferable)? I'm also assuming that sealed enclosures are not 'tuned' to any frequency...

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Music sounds better when it's loud.

Sealed boxes do have a tuned frequency Fcb.

This is the value fs rises to when placed in a sealed box.

At this frequency the woofer has the most linear motion and highest impedance.

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"I can taste the bubbles"..Stifler

i have some new s10l7s, both spiders are destroyed . even though i have them in small sealed boxes.follow kicker recommendations for frequency cutoff, and power handling,especially a system for daily use."1000+ rms is for specific tone use only, regular music or sweeps will result in a long wait for a warranty return" i still luv my solobarics [img]graemlins/thumb.gif[/img]

[ June 09, 2003, 02:47 AM: Message edited by: Loud Brown Kicker Colt ]

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I honestly perfer sealed boxes. Make them to almost the max specs for the sub and they sound killer. I have 2 friends with the same cars and the same subs and amp lol and one has an alpine type R (12") in a ported box and the other has a type R in a sealed box and I really perfered the sealed over the ported. If you like low bass then I would suggest making the box quite large(if you choose sealed). I had 2 10" L5's (that got jacked) and at first they were in a 1.5 cubic foot box and it sounded alright and then i made a 2.1 cubic foot box and it sounded killer. If you like a nice smooth bass with some quick bass response then I perfer sealed. thats just my 2 cents