Are there any generalities that theoretically apply to the SQ of a 10 vs. a 12 in sealed enclosure? (will say an Image Dynamics IDQ, as that is what I am leaning towards. I would guess the 12 plays lower and louder, but are there musical situiations where the 10 will outperform the 12?

With less cone area the 10" could be faster. But I dont think the differences will be audible.

^ x2 - but I think you can get the same response from a 12 as long as you give it enough power. Musically, a 12 inch sub should sound as good as a 10 inch sub but give you deeper and louder base due to the extra cone area. That being said - some people believe a 10 inch sub will play higher frequencies clearer than a 12 and therefore conclude a 10 is the best match for the system. This may or may not be true but I have tried lots of different 10 and 12 inch set-ups and the aside from the deeper bass from 12 inch - both subs played the higher frequencies to the cut-off in the same way.

It is possible that if you are planning on playing your sub at or near 200 hz, then maybe the 10 would outperform there - but I don't think so...

If possible, listen to both - then decide! Each to their own.

IDQ's don't really do well above 80Hz. They are awesome down to 20 tho.
The biggest difference between 10's and 12's is the transient response: with roughly the same motor pushing a smaller cone, the 10's should be a bit quicker on the drums etc. (all else being equal, which it never is) as opposed to the 12's moving more air at the lowest tones.

2 10" have a bit more cone area than a single 12, and use nearly the same box size, so for a bit more $ you can have the best of both worlds.

over the years i've come to realize a few things about car audio; it's never loud enough, it's never enough bass, it's never exactly the way i want it and i wish i had waited a little longer and put the bigger sub in. Maybe that's just me, but I always tell anyone that asks...put the largest ones that will fit in the space you have allocated. It just makes it harder for you to say later, "I want to add another one or I want a bigger one.", there just won't be any room left!

frickn YIKES !!!!

I see the special kool aid mix is being passed around...

Dude... the answer is 'it depends'... your best bet is to model the drivers you are looking at in the air space you have available to see how they will preform relative to one another....

As a general rule the larger speaker will play lower and louder... however for a given box allignment you will also need more air space....

All things being equal I would rather have a vented 10 than a sealed 12 [img]graemlins/thumb.gif[/img]

Thanks for all the opinions. Just wondering Dukk is your preference for vented SQ or SPL based?

SQ hands down. The extra output is just a nice bonus. [img]graemlins/thumb.gif[/img]

LOL, I still say this is the most opinionated industry next to cars and computers.
Personally I prefer sealed, with lots of good power.
However, I love my TL cabinet which is a port.(2-8's)