Ok so basically I'm torn between Kenwood KFC-P707 http://www.crutchfield.com/S-FLi5AIz...P707&s=0&cc=01 and Kenwood XXV-04S http://www.crutchfield.com/S-FLi5AIz...V04S&s=0&cc=01 . I'm going to build a custom box for the woofers to put right in front of my shifter (5-speed) and mount the tweets in my A-pillars. I have a 2001 f-150 4.2 ext cab btw. I will be powering either set and a 12'' DVC sub, probably a Rockford Fosgate P212D4 or Rockford Fosgate P2D412, unless any suggestions?, on an old school punch150 running both channels at 2 ohms. I was looking at these subs because they look good for low power applications and it will only get about 75 watts. Currently I have 4 Infinity Kappa 682.7cf running off a Profile AP1040 and 2 Infinity 10.1 Perfect's running on that RF punch150 I mentioned. The output just isn't enough for the subs and enclosure size so I have an Infinity 657 watt mono amp coming and new box plans to fix my crummy bass experience w/ the 10.1's. The RF will then go to the added components and 12''(for the low low's, the 10's are gonna be for my high tight rock bass). Right now I've got a short somewhere going to my door speakers( I ran all new 14 gauges wire), or a crappy amp because my door speaks cut out every now and then, so I have sucky bass, cutting out high's, and alternator/engine noise. So I'm gonna gut the interior, sound deaden the whole cabin and rerun my whole system again nice and neat instead of manhandling wire under the carpet. I think i pulled too hard when speaker wire was around a stud or something and tore the insulation, only thing I could think of to cause a short... I was crazy careful w/ all my connections. Also can anyone reccommend a good sound dampner? I've been looking into some of that paint on stuff because I've got a LOT of area to cover. BTW I am a total car stereo newb, but I'm smart, read a lot, and am very handy, any and all suggestions are appreciated, thank you. --DBM

p.s. when i say my high's cut out, my amp is going into protection mode

 

...Dont do this. Mixing sub sizes, brand, models etc is a no no. Youll end up with muddy sounding bass, and usually LESS output.
The sound of the sub is more dependant on the box than the sub size...to a certian extent...

Second Skin Audio, RAAMmat, and Elemental Designs are popular sound deadening materials.
Second skin is about the best your going to get, Raamat is a nice value product, and ED is cheap and affordable, but pretty low on the quality chain...

 

Sorry to Hijack but I had a question about the deadening material. What about using Edead to completely cover for the first layer then use Second Skin for the 2nd layer for the important areas like the door. What do you think?

 

Yes you can do that if you want to save some money. I think I would put the Second Skin on FIRST, then the Edead over it though.
That Edead will probably start pealing and falling off long before that Second Skin, and when it does, it will take the Second Skin right with it, if you have it as a second layer. Then you dont have anything but wasted sound deadener (the second skin)

Something to think about...

 

Can you give me some reasoning behind this? Why would having different size subs in a single operation make poor bass? What do you mean by less output? The 10's and one 12 would be totally seperate, diff box and diff amp.

Did anyone happen to check that link on the XXV-04S kenwoods? They say msrp 800 bucks and every other site on the net sells em for 100-150 more than crutchfield. Ebay is comparable but why pay the same and lose out on good service and warranty? Only thing that makes me weary besides not hearing them is I saw somewhere that they were offered w/ some kind of home entertainment package. Can anyone attest to their performance and if they are home or car audio?

 

You have two different subs with totally different response characteristics (sp) and thier sounds are not going to 'combine' to well.
By less output I mean not as loud. At times you would have the subs canceling each other out, and REDUCING the bass, instead of giving you more.

Now, if you really know what you are doing you COULD. That is if you have the 12 playing something from like 60hz down, and your 10s bandpassed from like 100-60 hz. That crossover point would be a major PITA, and you would spend months trying to tune it most likely. Where the rolloff of the crossovers meet, you are going to have your same problem as mentioned above. And at this point the crossover rolloff would be your least concern. In the end you would end up getting mad and taking a hammer to it all. It would be almost impossible to tune-pros would pull thier hair out for some time.
There is a reason you never see people running different subs...
In reality, the less crossover point you have, the better the sound most of the time, because you dont have to worry about blending. The way to accomplish this is with less drivers...


As I said before, a drivers ability to get low, or sound punch, or tigh, or boomy, or whatever terms you want to use, is dictated more by the BOX than the driver in most cases. You can make a 10 sound boomier and get lower than a 15, depending on the box. Of course driver specs do affect this some...
Boxes are one of the most overlooked things.

 

thanks for the explanation. I agree w/ you that the box is probably the most important aspect in determining the sound you get out of your subs. But a small sealed box (any other box design for them is out of the question) w/ 10's under my back seat isn't going to make my *** cheeks vibrate, ya know?Thats what I wanted the 12 for and I was gonna run independent crossovers like you stated... I'll take your word for it that it would be a PITA but I'm gonna try it if the new box and amp don't make these 10's pump because I have all the stuff (except the 12 but I'll just borrow one from a buddy for testing). If it sounds like doo doo and I can't get it I will just pull the 12. By next saturday I will have the boxes made and everything pumping so I will post some pics and let you know how it sounds.

Oh, and is the cancelling out of sound you mentioned (I've never heard this happen), caused by the subs playing diff frequencies? My idea was to bandpass the 12 and play like 40 or 60 hz down and play the 10's 100 hz and up, maybe higher depending on where the LP range on the crossover stops, it might be 120.

 

hmm. looking at the crossover I dont know if i will be able to set the 10's like that...

 

Haven't got this set up, but my Mcintosh amplifier's user guide suggests that the best sub set up is to have two of the same size, one bandpassed around 150 hz with negative db's and the other low passed at 80 hz down with db gain for the thump everyone likes. The Mcintosh amplifier has it's own crossover selections on board to set this up.

Reason for setting the one sub to the bandpass around 150 is that most auto setup's happend to have a length average that produces a bad harmonic at about 120 to 150 hz. So setting one sub up with that bandpass around that point with negative gain along with the thumper, corrects that SQ.

One presumes with this set up that everything is properly sound deadened...otherwise I don't think it matters if you just have the original steel body with carpet over it....

AudioAugs