Combo of different size subs.

[Rusty Holden]

Just had a thought, has anyone tried this?

Was thinking of using 2 different size subs in an install. I listen to mainly drum & bass and dance music, so to get a nice tight kick as well as gettin right down there and grunting where it matters.

To achive this, would it be useful in running a 10" in a sealed box and a 12" in a ported box. I was thinking Jaycar Response double stackers?

[hcca]

I think you'd be better off getting a 12" or two and some good 8" mid-bass speakers mounted in your front doors.

[Rusty Holden]

8's kick pretty hard? Any subs going in are going to be unseen. So 8's hangin off the doors are kinda outa the question unfortunately!
Will 8's kick as well as bring out the vocals and snares and melodies etc?

[hcca]

8" midbass speakers do precisely that - MIDbass. A sub is designed for low frequency (like 50hz). If you listen to dance etc, there is a lot of low bass, but there is a surprising amount of bass between 50hz and 150hz and a midbass speaker will do this great. It will also improve your front stage (dunno what front speakers you are using). Using a 10" to act as a mid-bass speaker will move your sound stage to the rear of the car (bad).

Anyway, if tune your subs to play higher than about 80-100hz, it's going to effect the front stage so ideally they need to be set at or below this. This can leave a bit of a hole in the music if your front speakers aren't capable of playing lower than say 250hz. A 10" sub will be ok, but if you really want lots of bass, go for a 12".

The more speakers you can get at the front of the car the better so 8" midbass's at the back is going to be shit. They need the door for the enclosure. If you don't want to cut up doors, then they're out of the question.

Really though, how much bass do you need? I have 2 12"s and 6" splits in the front and there is enough bass to kill small animals.

[Kinks]

8's are too big for vocals, snares etc. At minimum you need 1" tweeters, a woofer absolutely no larger than 6.5" (preferably 6" or below) and then subs. 8" sub + tweeter = very horrible midrange.

Remember that cabin gain in a car makes a big effect at 40Hz and below, so a sub that is flat down to say 25Hz in free air (as a ported 12" would be) will have HUGE amounts of low bass when put in a car. Ported subs tend to sound shit for exactly this reason, they have the bass extension but coupled with cabin gain they resonate themselves too much and the car too. You actually want to design a sub that rolls off at very low frequencies that approximately matches your cabin's tendency to boost low frequencies.

That is, of course, if you care about your music more than you care about bass. If it's just bass you want, go nuts :)

[Rusty Holden]

I JBL 4X6 two ways in the front (nice and crisp and fit original plastic mounts) :)
I had some pretty dodgy 2X12's behind the seat but they got flogged.
Im really after quality rather then quantity, therefore i would love too be able to hear the low freq's without having to crank it (not really one to attract attention) Thats why i wanted to go the 12" double stack, i hear they are great at getting right down there, even at low volumes.
Will 6-6.5's on the rear parcel shelf still give a decent kick when amplified?
3-ways or splits?

(BTW its a U12 Pintara we're talkin about) - i know, sounds rice but i like good QUALITY sound. Not trying to be a doof-doof head in a shitbox.

[hcca]

Sorry.. should have mentioned that I meant 8" mid-bass's in conjunction with something else, be it co-ax's or splits.

If you're after quality, you probably want to spend a minimum of $200 per sub. Then you got to build a box, and you need an amp. A good sub will play a lot better (sharper, clearer, louder) than a cheap one anyway.

Chances are your front co-ax's are producing less than optimal bass due to their mounting (I know you want factory, but factory is less than good always). Plastic mounts suck - you need something non-resonant and sound deadening like wood. Actually, wood is about all you'd use. Mount the speakers on MDF and seal as well as you can between the front and the back of the speaker.

Splits will give you more bass than co-ax's which you have. This is because the midrange speaker is dedicated rather than trying to do everything. A reasonable set of splits start at around $300. Don't get 3-ways - 2 ways are quite sufficient (and more efficient) if you go the co-ax route.

Don't bother with rear speakers unless you want to be nice to people sitting in the back seat and don't amp them - run them off the deck.

Personally, I wouldn't advise you to get subs unless you're wanting to spend lots of money because you'll need to upgrade everything else to keep up with the subs. Start simple - get a small amp (like a Kicker 35Wx4 or similar) and a set of splits. You'll be surprised how much bass they produce compared to co-ax's. Then if you want subs, you can add them later.

[tomee]

dont bother in trying to mix sub sizes togther... theres no point, altho ppl have done it it takes alot of time to make it sound right with no issues....IMO jsut stick with the norm.

K.I.S.S = Keep It Simple Stoopid :)

also be good to make ur sub size around 2 inchs from ur biggest mid bass driver, eg: 6 = 8sub | 8 = 10sub
IMO

[teK]

Tomee: Yes that's exactly right, the more speakers you have the more overlapping response curves and the more inconsistent your music is going to sound. Multi-size sub configurations aren't worth the trouble, just think about how terrible the B4 is because they didn't set up the turbos properly ;)

HCCA: If you have a set of splits with the same size midbass driver as a coax (of the same efficiency, power rating etc etc), they will create identical levels of bass. You say that splits produce more bass than coax because in the latter the midrange is trying to play everything. This is not true since coax are really just split speakers mounted together for ease of installation but still have individual drivers to play each frequency range. The advantage of splits is to allow exact placement of each driver for good imaging. Subs should definately be lowpassed to play below 100Hz though, any higher and you have VOICES played through the sub, yuck.

Kinks is right in saying that a 8"/tweet split pair would sound horrible. It would be starved of the highs that a 6.5" could produce well. The ideal split pair would compose of 8", 5.25" and tweeter. You can see this in high end installations and they sound phenomenal. My car resonates around the 42Hz mark too, and this also coincides with the peak response for my 12" ported box. I could have built a box that had an earlier/sharper rolloff but I like low rumbling bass :D

For D&B you're probably best off with a 6.5" coaxial in the front doors for ease of install, coupled with a 10" sealed box in the boot. If you're more into Jungle then a 12" will play better and lower, but if you want the boomy rumble sound you get in a basement party then go 12" ported box :p

I'm not sure what you define as "dance" but the tracks you hear in the charts would play well on a 10" sealed since they are mostly written for people with mediocre systems. House/Trance would probably play better on a 12" ported.

The Jaycar response subs are quite good for what they cost, but also have a look at JB around this time of year when they have their clearance sales. Kicker, JL, MTX are ones to look for.

If you are on a budget then I suppose you could suffice with some 6.5" in the rear parcel shelf. :o Just buy coax though, the superior imaging of splits if you install them there will be wrecked after reflection off the rear windscreen.

Good luck!

[Rusty Holden]

Thanks a shite load for all the info guys, really appreciate it! Now to decide should i give it a go in my current run-aroud or wait til i get something a little more decent!?!
Thanks Fellas' ;)

[hcca]

Tek, If you can find some co-ax's with the same efficiency as even a dodgy pair of splits i'd be impressed. Co-ax's are a compromise. Having a tweet or two sitting in the middle of the speaker affects cone strength etc. Also, splits have separate crossovers which better define the range of frequencies that each speaker is playing.

[Kinks]

Don't forget that bass output is sensitive to sealing ie you have to keep the front air mass and the rear air mass completely separate - leakage kills bass output. The tweeter is mounted on a stand in the middle of the speaker, there is a hole cut in the centre of the woofer and it slides up and down the stand - rather than the whole tweeter assembly moving up and down which would absolutely KILL the quality... So coaxials never have the quality, rigidity and sealing to compete, they're a compromise from the start.

[hcca]

Rusty,

The beauty of a stereo system is that it can be moved between cars.. about the only part that might not go straight across would be a sub box but that's not the expensive bit. I have a somewhat elaborate system in my current shitbox and now that i'm building my new car, i'm glad I bought the stereo years ago because it means I can spend more on the engine (which is starting to cost waaay more than I thought) :)

[teK]

HCCA: Yes that's why I said compare midrange driver with coax of identical specs, power handling, efficiency, response (for midrange of coax) etc. We are comparing bass output not quality so can leave crossover out of consideration. I'll agree with cone strength on pole mounted highrange drivers, but there are also coax that have tweets suspended across the edge of the speaker basket and have a fully rigid midrange cone.

[snavy]

i would recommend it, but if you want to just go for it. But if you want more response from your subs, go for 10's, the larger the sub, the more time delay, ill just go 12's they are good for just about anything.

[tomee]

Originally posted by snavy
i would recommend it, but if you want to just go for it. But if you want more response from your subs, go for 10's, the larger the sub, the more time delay, ill just go 12's they are good for just about anything.

any sub can have time delay just depends on how u set it up..
ported box usually have a delay if u play some fast techno beats