Hi guys...

Just here to stir things up a bit and learn some more. I'm redo-ing my stereo, AGAIN.

From an acoustical standpoint, I'm wondering what you guys think about sound quality from a false floor enclosure in the Z (meaning a fiberglass box that takes the air space from the removed spare tire well) versus the SQ of a fiberglass box underneath the strutbar.

In my situation, I am using 12" subwoofers (a pair of them).

I'd like to hear a good debate on if there are any differences in sound because of these install locations...please don't post a simple "i've got a 12 under the strut and it beats yo!" I'm looking for a scientific type explanation...everyone says bass is non directional..but I've proven to myself time and time again that positioning/install can make a huge difference.

Educate me ahaha...what would be better? I'm doing two amazing 12's *shhh* with a lot of power. It's a showy type setup..save the audible warnings for my grandpa.

ravi

 

I wish i could hear how 2 12's sound in a Z. Why do you live so far away? post some insatall pics... I think they would sound better facing up in a sealed enclosure (false floor).

 

haha ravi,

here is my take. the key is often to load the subwoofer again a solid surface. in an enclosure car's trunk, the most solid surface in the trunk the back wall, hence in most cases, its louder to face hte sub backwards.

in a hatch its totally different, but the back wall and the hatch itself are solid loading surfaces, and both would be ideal to fire a sub at.

i have done many many hatch backs with subs facing upward and backwards, and honestly, there is no real difference. also, this varies car to car of course, but in your case ravi, you wont notice much of a different, if any at all, with different set ups, i would go floor up in your case.

in terms of sound quality, as long as the cnlosure is well built and the car is well tuned, tere will be no difference waht so ever...

b

 

Thanks guys.. precisely what I was expecting...

I know we've got some more audio gurus in here...Jim? where ya at..

ravi

 

it would be better to go with a ported box dont matter how it sits. but for 12'' i would put them in the floor.

 

Ahh. I'm not much of a ported fan..no matter how its tuned thus far. I like the way sealed sounds betters, esp in a cabin the size of the Z.

I had a 10w7 slot ported to 32 hz in the z, and was not impressed.

Ravi

 

If you build a true subwoofer - say one crossed over at 80 Hz or below - I don't think you're going to notice the difference. The volume of air in the cabin is so small compared to the wavelenght of the frequencies that they're folded a hundred times about already - another fold or less isn't doing much.

A properly constructred box will make the difference rather than if it's pointed up, backwards, or forwards. The box has to be air tight (completely!), solid and free from vibrations, and mounted firmly into the structure of the car. My boss had built his own speaker box and left a 1/4" hole in the side where he drilled a hole to run the speaker wire it. You could feel the air pouring in and out of that hole when he turned the music on. I had him seal the thing with RTV and the whole sound improved for the better.

High end home theater and stereo system speakers use a bunch of different designs for their subwoofers. Crossed over below 80 Hz it's really hard to find them. Moving them about inside the room makes a big difference in the low frequencies ... but then you're talking about rooms with thousands of cubic feet of volume ... not ones with a dozen like our cars. The Klipsch Klipschorn are designed like the under strut subwoofers to load up a corner - our trunks - and to reflect the sound back into the room - our tiny cabins. The tweeters and midranges do not benifit from this loading and must face the listener directly.

The Bose 901's with their direct/reflecting system aren't found in true audiophiles homes.

The suround speakers in a home theater's 6.1 or 7.1 system are programmed/engineered to have reflections by design. The sound engineers send the proper sounds to those channels for that exact effect.

If you're looking for insane amounts of ear numbing bass than a slot resonator will deliver that effect. A sealed box delivers cleaner and more accurate sound with a simplier to design and fit box.

 

^^^^^^ very well said

paul i think you would agree too, two idmax 12s with 1000watts RMS from a quality amp in a quality sealed chamber will produce more than enough bass for 99 percent of hte population in a 350z.

 

Oh for sure...but that 1%...

Just an fyi bing..my last setup was a sealed 1.1 cu. ft 12w6v2 off of about 5-600 watts, in an under strut enclosure and I was very pleased. If I remember I was able to get the QTC to .707 at that volume etc.

Bass filled the cabin...as you know this is a show-off setup I just hope it does the trick..SQ should be insane..SPL I'm sure I'll be shocked as well.

Ravi

 

i just posted in audio forums about my 3 10 inch fiberglass sub enclosure from ebay and how much airspace it offers

 

heheh, i know what you mean.

my set up is a single idq12 in a 1.2 cub feet sealed enclosure with only 190 watts of rated arc xxk power to it and i have a volvo wagon i certainly does enough for me...hehe

that 1 percent would go do slot ports in walls hehe

b

 

LOL and they probably are rocking escalades!

 

I'm very happy with a single 12" in a fibrglass tirewell facing up. I think you will be happy with either configuration. I have more than enough bass with the 2" and a JL 500/1, can't imagine how 2 would sound..or how you would fit them both without raising the false floor. With fiberglass I was able to make the enclosure 1 cft and 6.5" depth...I had to use a 1/2" ring to raise the driver up slightly. If you have deep woofers this may be an additional issue

 

I definitely agree with the solid surface theory, kind of speaks to the effects of corner loading. Both in the home and car.

Between these options I think any difference is minimal. What's have you found GQ?

 

Actually,

My results are also conclusive to what everyone has already said here.

Time and time again, car audio and its associated quality comes down to one thing-- a good install. The location doesn't really matter, but for some reason people have told me that the false floor will sound "better" than the understrut scenario. It makes sense to me (kinda) but I can't exactly prove it yet.

Solid surface theory makes sense from a physical standpoint..after all sound can be "directional." I think in the Z either install will yield positive results (although both have pros and cons from a show and trunk useability standpoint). I'll post my findings. After having three different subs in the z with different types of enclosures and equipment, I have not been completely satisfied. My last setup (single 12W6V2) was my favorite thus far. Far superior in sound IMO to my 10W7 tuned to 32 Hz.

I am determined to get the exact sound I am looking for this time, which will most likely only come from the pair of 12's in the false floor.

Thanks all!
Ravi

 

Ravi,

Simply put, you won't notice a difference. Based on the amount of air you will be moving, loading become nearly irrelevant for you.

I don't feel like explaining.

Paul ... the K Horn reference above is quasi correct here .. except its design is more a close range quarter space loading ..not necessarily what is going on here, but close.

Jim (used to work in K town )

 

i will try my best to take care of the "well installed" part lol

as for how to do it without raising hte floor? hehe, i guess eventually the pics will tell

b

 

Bing should run for president haha.

This guy is awesome.

 

nah, dont say that lol i am no where near that good of a fabricator, many of hte guys around the country can do stuff that i can only stare and wonder and there are guys who know more technical knowhow on this very forum I just pay close attention to detail and make sure everyhting is done correctly and cleanly...

okay, now i need to start on this G35 SQ install

b