your thoughts

Picture this: 2 12" L7's (sealed) @ 800 rms a piece, 2 6 1/2" (front) and 2 8" (rear) kicker mid-bass @ 100 rms each.  I need 2 10" subs that especially play the higher-low frequencies well without popping (around 60-120 hz) that are capable of at least 300 rms.  What would you guys put in?   

P.S.  they'll be in sealed enclosures

So you want 2 L 7's  sealed,  they will be louder ported just to let you know,  and you will be using 6 1/2's and 8 inch speakers,  so why do you want  10's? if you x-over the 8's properly, you won't  need the 10'sand if you use the 10's and the 12's you will have to have the 12's play 50hz and down , and have the 10's play 50 hz and up,because if the 10's and 12's play the same freq. you will get cancelation, if it was me i wouldnt use the 10s

                                        Keith- Owner of Hardcor Audio

I have 2 L7's and 2 other 12's as well as running the same power at the moment.  One of the reasons why I'd like specific 10's is becuase I've got a huge output of the gut-wrenching bass, but none of my subs are really geared for the higher stuff.  One 12 is an L5, the other is a comp vr.  I know, I know, but it was either put them in or put them in a closet.

Ported is out of the question, I hate them cause they're too boomy.  I prefer a tight, flat response which is why I'm looking for these 10's.

As far as the mid-bass are concerned, I want to use those for nothing lower than about 100 hz since they'll have plenty of juice and I don't want them popping.  This leaves me with a gap from something like 60-100 or 120 hz.

And in case anybody's wondering, I'm trying to get a very loud but CLEAN sounding car (eg.  I'd rather spend more money to get a bigger amp than use a ported box).

8" and 10" are going to be way too close to each other for your application, it may result in a whole pile of cancellation.  I personally would use one or the other. Your right to head in the direction of a sealed box, do it with a pair of 10's, nice small sealed boxes, powered properly, bandpassed with a proper outboard croosover like the Audio Control 4XS and it will do what you need it to.

Most vehicles have a nice natural midbass hump above 150 hz and usually fills in by itself. Your 10's should easily be able to play in the area from 80-150 hz. A SPL system usually has it's highest SPL Level up around 70 hz in most vehicles. I would be using the largest drivers to take advantage of this, not the smaller drivers.

Yea, I've always preferred the sealed and I've never used anything else.  After hearing the other types I knew it was the way to go for me.  Your suggestions are most welcome, but I have to say that I'm going for something specific.  Perhaps some more info will help:

I'm 24 and I've been installing and building systems for 8 years.  I've done everything from the basic mids and a sub up to the more elaborate multi-component systems.  I'm certainly no pro, but I have some experience.  I also have a recording studio (the real kind with machines and stuff, not a computer) and these two are closely related.  In my studio I use monitors (speakers) which have a flat response through the spectrum (less than +-3db 10hz-20khz).  When I listen to a song or mixdown through the monitors, in particular the bass to mid-range, I hear everything as it should be.  When you playback the song through any car stereo (with the exception of comp systems), you hear something totally different in regards to the low-end.  My goal is to put something together that sounds great, loud or quiet, top to bottom.  My main concern is 400hz and lower, and I really want to be able to balance it out using the x-overs and amps.

Here's a more detailed description of what I have in mind (all frequencies are approximate):

Front:

6 1/2" components (400hz+), Kicker 6 1/2 mid-bass (150hz-400hz)

Rear:

6 1/2 full-range 3 or 2-way (300hz+), Kicker 8" mid-bass (120hz-300hz)

Trunk:

10" subs (70hz-120hz), 12" Kicker L7's (20hz-70hz)

Everything is in pairs.

I'm going to have an extensive x-over network since there will be 6 or 7 amps involved.  I trying something a bit out of the norm, but I think something like this will give me the most versatility to "zero the plane".  Phase shouldn't be a huge issue since all x-overs will be hard (at least 18db).

I know I'm going out of my own way to make this more complicated than it could be, but I want to try something different.  The problem is that I'm not sure which 10" subs will do the best job playing the higher fq's.  I've used 6 different types of subs in my car(s) before, but I've never had them for playing just a higher-range at high volumes.

I would think that clarity would be a key aspect for the 10".  What I would likely wind up doing is making a fiberglass box for each, having a medium to large sized sealed enclosure to avoid popping.  Right now I've got my other 12's in glass boxes I made and my Comp Vr's in a box that's on the small side (but not too small).  The result is popping when I try to squeeze out higher fq's from it because of the high sensitivity.

I hope I've given enough info for a good recommendation.        

You don't really need the 10's as the 8's will easily go down to 70 Hz, but assuming you do use them (and all 10 to 12 channels of amplification your system will need) go with a 10 that matches the timbre of the 8's.  Use a loudspeaker from the same manufacturer and same line.  Power them from the same make amp at the same relative power levels.  This way, you won't hear the crossover.  Use sealed enclosures all around, certainly.

If you are using your car system to check the mix from a studio, you are making a mistake to try and build a perfect replica of the sound a studio monitor can achieve.  You want to listen to your mix on systems that will simulate what your customers are likely to use so you can tell what it sounds like once it gets into their hands.  In the studio, I use three or four systems to check a mix after the 2-track mixdown done on the big monitors, including a little Auratone mono monitor that simulates the sound quality of AM radio and the base factory system on a Honda Civic...

Ahhhh... another sound engineer!!  I agree with you completely about using different sources after mixdown, but this is entirely personal.  I don't want it as an expensive monitor, but I do want to re-create the seamless transition from low to high found in studio monitors (as you had stated) with the effect being that  "there aren't any subs at all".  Even if they're rattling the doors.

I'll take your suggestion and see if I can't find something suitable.  Thanks.

P.S.  Do you work in a studio, or do you have your own?

I've worked in several studios over the years and am part owner of a small independent studio.  We do a lot of video work and some local band stuff.  100% digital (Pro Tools on a G4 with lots of outboard toys).

If the system is for your own enjoyment and you have the money and time to do it right and you want flat frequency response, I'd have to recomend you not use ANYTHING from Kicker.  Don't get me wrong, they are a fine company with fine products, but in my mind they are definately mid-line and may not be accurate enough for your critical listening tastes.  Spend a little more and go up a couple notches in quality, at least in your component sets and mid-bass drivers.  I use SEAS components and Vifa/ScanSpeak 7" mid-bass.  I'm expeimenting now with an Image Dynamics IDMax 12 sub.  My RTA tells me I am near flat from 25Khz to 30 Hz, down 3db at 24 Hz, down 6db at 16 Hz.  You will definately need an RTA to get a complex system like you're anticipating set up properly.

Also one other observation.  Youe target X-over point from the 10 to the 8 is 120Hz which is right at the normal cross point from the 3rd to the 4th octave.  I recomend you adjust that target up a bit to say 180 or so to get it into the 4th octave and avoid a potentially harsh and noticeable crossover point.

Cheers.  Let us know how it all works out.