Can 12's and 8's be on the same box?

[T3mpest 10+ year member]

The size in and of itself won't cause cancellation, but the differences in parameters will cause some. It's not nearly the total cancellation that most seem to think that it is but it does make for a ragged frequency response as you alluded to. The only way it woulld affet the freq response is if some interference occurred, both destructive (cancellation) and constructive (reinforcement). This doesn't just happen with subs either. Any time you have different drivers playing the same freqs you will have the same problem.

True, but wavelengths are much longer in the subbass region. Whereas this is critical when we get into midrange and tweeter areas, for subbass, the differences in the drivers response in terms of causing cancellation is probably minimal, assuming they are in mechanical phase with one another. The irregular f/r is more a product of the drivers inherent frequency response in their enclosures not matching. I have a feeling if the box volumes were setup very carefully, using each drivers true T/S parameters, you'd end up with something that's fairly flat. Not to say it'd be worth all the effort, just making a conjecture.

 

[helotaxi 5,000+ posts]

Without total control of the eletrical phase of both drivers you would not be able to get them in phase to the point where it will be total reinforcement. The group delay characteristics of each driver are going to be different and unless you can figure out a way to get them perfectly sync'd up, you will get some cancellation and muddiness of the bass. Think one big smear in the low end. The closest you will get is going to be using sealed boxes on both. Make one or the other ported and the group delay curve will become a killer. It COULD be set up to work, but in the end would be a ton of trouble for no real benefit.

I've got a cool little processor that I just picked up that would allow me to approximate the effects in-car with my subs wired the way that they will be once I get my new box installed. It would have to be an in-person demo though, until I can get an RTA program and measurment mic for my laptop at which point I could put up some respose graphs.

 

[SeaKid 10+ year member]

LeeAudio Member

Join Date: Feb 2007

Location: lake park fl

Posts: 75

Ummmm....?

even better, is that the thread starter has 544 posts lol

Wow, just because you recently joined the forum or don't post much doesn't mean you are underqualified. Someone could have been messing around with car audio for 20+ years and just now decide to join to forum. Whats up with rating people off of post counts? All that thousands and thousands of posts say to me is that you spend WAY to much time on here.

 

[DeuceLee 10+ year member]

some of you idiots need to chill the hell out...

he came and asked an honest question, wasn't being ignorant about it, wasn't showing off his 13w7 and 10w6's in the same box sayin they were the shizzle, wasn't being an idiot and trying to misinform everyone...

all you could have said was it wasn't a good idea or whatever...or explain, or plainly say no...

some of you fools are immature as hell by thinking you're cool cus you can say "go and die"...

grow up

 

[Octavio 10+ year member]

the answer to this thread is no ..... thanks guys

yes if done on difference chambers

 

[audioholic 5,000+ posts]

As Ive said 1000x here before, there's really no good reason to try and split the relatively small frequency window a subwoofer is required to play down even smaller. If your sub system wont play 30hz to 80hz or so, the problem is your setup, not a lack of speakers.

 

[Imshirazy 10+ year member]

Octavio, I just want to know your reasoning.

Yea it's really not worth it to have them in the same box...

If anything, separate boxes

but if you really want to notice any type of difference, i personally would put 8s in the car and leave 12s in the trunk

I have a 2x10 and 1x12 setup once, I tried making the 12 handle 20-50 and 10s do 50-100

to be honest, it took ****ing forever to make sound good, tuning to make them the right volumes etc and sometimes it sounded like crap

what was worse was that when I finally got it all done, I put in some rap cd, i don't remember what, but the music had mostly 50-65 hz tones, this made the subs go nuts, it was incredibly unusual to hear

Btw, one sub vs. 2 subs doesn't even always make much of a difference, let alone 2 - 4