AUDIO ADVICE

[eben]

Here are the files... I didn't see any copyright notices and there are links in there back to the originating site.

[AirPower]

All I can say is - read the doc files (word) first -the xls files can seem confusing. (was to me in any case) BUT the correct enclosure size is -- very--- important to get the most out of a sub

[karmakoma]

Great links. You wont believe how much better a sub sounds when installed in the correct enclosure. Years ago I built a "proper" enclosure for my pioneer 10" sub to use in my citi golf, and it blew many a 12" sub of higher power away simply because it was installed correctly. IMHO sealed is easier to get right and it gives you very nice "tight" and responsive base.The kind you need if you enjoy rock and pop music. If you want to see how low you can go (rap, r&b, drum n base, techno etc), then ported would probably be the appropriate option, but more difficult to get 100% right. For sheer volume, bandpass all the way. MY 2c.

[Tony Z]

I cant agree with you there..... then again, my tastes are prob different to yours so I look at it differently....
My experience with those enclosures...

Sealed is the best by far, but you need money to make it work properly. i.e. a good sub and a big amp.
Vented boxes are loud but their clarity sucks. And no, they dont go as deep as a sealed box, they just get the lower frequencies louder. If you are looking for the freq below 30Hz, then you need sealed or bandpass. Most basslines in R&B and the likes are in the 45Hz region which is why they sound so good in a vented box (pure distortion to my ears).
Bandpass, pretty much makes a few frequencies super loud and kills anything else. I have heard a few and they just blow hot air, making a few loud noises occasioanlly. I dont like them at all.

I am into clarity all the way and will go sealed everytime for that reason. If I dont have the volume needed, then I'll have to make a plan to get more power....

[AirPower]

Totally true - vented - the vent is tuned to a certain freq which then boost that specific freq.

Bandpass is easier to make, but it's bigger, usually. Problem is the sub is fed a full freq (bass + mid + high) then only the bass is allowed out of the enclosure and the rest is wasted sound.

Sealed is the best in my opinion, unless you're going for max decibels - then a properly tuned port adds several db's.

Mario

[karmakoma]

One thing we all agree on then, sealed is best. I am also into clarity,not volume so agree with you both in that regard.

I still think getting a ported enclosure tuned exactly to the frequency you want is more difficult than building a good sealed enclosure, hence my comment.
Airpower, I think perhaps you described bandpass the best.

[Matt]

if u looking for deep/low bass....dvc sub and a ported box.
if u wanna take things really serious.....go to a recognised installer, because there is a hell of a lot more to it than just
big sound = big results. every make of car has a different resonant frequency.

a smaller sub in a sealed box does give tighter bass.

its all one big formula....the bigger the diameter, the lower frequencies can be reproduced with less effort.
and the more coils...the less high pass u get. thats why quad coil subs are absolutely incredible.

sealed boxes, if u making yourself, are more forgiving(if u dont have the exact dimensions)
ported boxes, are not so easy, at all.
that theory, bout putting decarum in a sealed box-works. if u r building a sealed enclosure and dont have much space
and scarred the volume is to small...put that shit in. it bluffs the speaker its in a bigger enclossure

[bugspray]

I think the ported/sealed things being done to death now...

[Matt]

true, i have a sealed-its ok.
got a new deck...so stoked, the old jvc was poked.

[eben]

I prefer infinite baffle design

[Tony Z]

I prefer infinite baffle design

in a car???????

[eben]

I'm messing... giving you more things to argue about

[eben]

Some infinite baffle 'enclosures' have used an adjoining room, basement, or a closet or attic.

[Tony Z]

what about a labyrinth enclosure?

[jmvv]

My two cents worth.

For purity (not clarity) the sealed box sounds better because it has a flat frequency response and thus is not so prone to "booming". The draw back is that a lot of this bass disappears when you start to travel at speed and you end up hearing only the midbase and tweeters

A properly designed ported box wil have a "bump" in the frequency response graph.The benefit of a ported box is that you can move this "bump" by tuning the box correcly and by manipulating the box size.

Tuning the box correctly to a specific resonant frequency allows you to cater for personal music taste and/or compensate for specific vehicle accoustic shortfalls. This allows you to generate more bass at the frequency where the bass normally "disappears" if a sealed enclosure was used, thus

In most of my installs I use a ported enclosure, tuned to the vehicle's fundamental frequency. (play around between 42hz and 46 hz) With proper amplification (Amplifier with proper RMS wattage) Dependieng on the type of subwoofer and the amplifier power, I have seen up to a 6dB gain at those frequencies.(Effectively the subwoofer sounds two time louder at that frequency)

What this means is that while travelling at 120km/h in an aircooled Beetle with the window down, I can stil hear the different base tones from classic rock and roll that would normally "disappear" because of mechanical noise in the car.

Personally, I like to build a sound system that sounds good with most types of music whilst driving because that's how I spend time in my car and I like to hear what the artists have recorded.

A lot of excellent SQ cars do not sound so hot once the ambient noise enters the equation when the car starts driving.