Is a sealed enclosure for speakers good or bad?
how much airspace should I give them?
Whats up people?
The thing about a sealed enclosure, as long as the speaker is rated for it is that they are typically smaller than a ported one. That said, if sound quality matters to you, I personally like a ported enclosure and would sacrifice the space requirement to have one. I went with a 10 inch sub instead of a twelve so that I could get a ported enclosure. Check the FAQ's at the top of this forum for a really nice writeup of the differences between enclosures.
Gotta keep on livin', L-I-V-I-N
bone stock z: i said speakers not subs . . . . . that being said i realize subs are speakers but i meant like 6x9's
sndsgood: i am not sure if you are meaning like 6x9's or not so could you please elaborate
what i want to do is fiberglass some pods in the back for the 6x9's because they are being beat up by stuff and i think it would help protect them as well as maybe help out my sound quality
Whats up people?
i would Dynamat the inside of the pods you are making as well .. that would sound really tight
Really depends on the speakers. Also depends what the recording studio was using when they mastered the songs
ok that brings to me a question...
I have a pair of MTX 10" subs in a bandpass box...
only thing is the trunk i had them in is bigger than the trunk i now have in my 91 sunbird vert.....
i am not so worried about the box....
the way the bandpass is made the subs face each other at an angle with plexiglass covering the big hole...
would it be good to cut the box apart at the big hole the plexi glass covers & turn a dual bandpass box into 2 ported boxes for these subs... i only want 1 in my trunk with the new amp i am going to get
looks like this
then i will have 2 boxes once cut...
cause the enclosure size is perfect for these 10" subs...
they are old school...
mtx roadthunder two subs...
I bought them new in 1995 & then they went into storage till 2007 inside the bandpass box... never got to hook them up at all for 12 years
then i had them in my altima with a simple old school 2 channel amp & seperate electronic crossover.... they hit Nice
so like i asked... would it be an ok thing to do to cut the box apart so i can have a single ported box instead of dual bandpass?
please let me know
Thankz
MikeC!
91 sunbird Convertible
3.1 with an automatic
http://www.cardomain.com/ride/3038464
i highly doubt that there is enough air space in the ported part for your speakers. it works for bandpass, but not straight ported.
"I did it because I wanted to see what it would look like. You should be greatful that I even told you that it would look good. If your to dumb to use photoshop and change the color of your own car then you don't need to see it changed. I'm not going to give my work away. I'll sell the pic to you though for $15."-Adam Kalin
^^JBO is about not being that guy
ok then....
here are the specs for my mtx subs...
tell me what would be best
4 ohms
re(dc resistance)- 3.02 ohms
levc(coil inductance)- .52mH
SPLo (reference efficiency) @ 1W/1M- 92db
Fo (free air resonance)- 28hz
Qms (mechanical Q) - 3.566
Qes (electrical Q)- .424
Qts (total Q) - .377
BL (force factor) - 5.85 N/A
Effective Piston Dia. - 8.125 in
Vas (volume acoustic suspension) - 5.6ft3
Xmax (excursion) - .17 in
rms - 125 watts --- (I know not a big power house but they sound good)
mounting dia. - 9 1/4 in
mounting depth - 4 7/16 in
speaker displ. (inside box) 255 in3
speaker displ. (outside box) 140 in3
says the frequency responce is - 28Hz - 2.8kHz, +/- 3db
so if cutting the bandpass apart is not the answer.... can someone tell me what the dimmensions of a good sealed or ported box would be... the tech sheet shows both, but gives no f'n measurements for either sealed or ported
for a sealed enclosure it says
minimum size box is
box volume (Vb) 1.0 ft3
F3 (-3db) - 59hz
Qtc - 1.01
Ripple(hump) 1.3db
Medium size is
(vb) 1.25 ft3
F3 is 56hz
qtc is .91
ripple is .75db
maximum size sealed is
(vb) is 1.75 ft3
F3 is 54hz
qtc is .79
ripple is .18db
then it goes on to show minimum, medium & maximum in a ported box along with port lengths depending on length & size around of tube or if it is a single or double tubes...
I just want to know what size to build a box for 1 of my subs is all
can someone help please
thanks for helping a newbie
MikeC!
91 sunbird Convertible
3.1 with an automatic
http://www.cardomain.com/ride/3038464
How much room do you have to work with?
sealed is always going to sound better, not too noticably tho. however a ported enclosure always is going to be louder and/or more intense.
i have to find some of my old box building software for someone else as well, would you like a copy when i get it?
bradsk88 wrote:The Daleosis wrote:sealed is always going to sound better, not too noticably tho. however a ported enclosure always is going to be louder and/or more intense.
MYTH
do you have proof to back this claim up?
ok lets see how much room do i have to work with... the trunk of my 91 sunbird convertible...
only want to put 1 10 in there... that way i have some trunk left for like when the old lady & I go get groceries... that type of thing yanno...
I am Thinking Sealed is how I really want to go.......
YES I would Love a copy of your box building software when you find it...
cause i can build the box, just not sure what my dimensions should be...
i have access to a box for a 10 right now that is sealed, but i don't think it is big enough & dont want a bad sounding sub in my trunk
so n e ways let me know on that software...
Thanks
MikeC!
91 sunbird Convertible
3.1 with an automatic
http://www.cardomain.com/ride/3038464
They say nothing about sealed being better, just easier to make, and less steep of db dropoff at the edges. Properly tuned ported boxes are more efficient and will get louder.
Ported systems are all around good performers, and most commercial home speakers use some type of ported enclosure. Automotive subwoofer manufacturers also like the ported enclosure, and most design drivers for this type of installation. The tuned port in these systems increases efficiency by nearly 3 dB in an optimum enclosure, and the roll-off frequency can be much lower, often by as much as 1/3 - 1 octave below a sealed enclosure. Think of the extra 3 dB as equal to the output you would get using twice the amplifier power on the driver. Add several ported drivers together and you can achieve impressive SPL's indeed! Because of the ports damping characteristics on the driver above Fb, distortion levels are also lowered because driver excursion is less.
So, with nothing more than a properly designed optimum vented enclosure, you have very efficient bass reproduction with several advantages over an optimum sealed enclosure.
So, why in the world would anyone waste the time designing and building a sealed enclosure? Like anything, there are compromises in all designs, and ported systems are no exception. A very clear advantage for a sealed enclosure is simplicity - you can get good performance with nearly any driver with an EBP of less than 90 in a simple sealed box. Enclosure volume is not critical with these designs, and a volume change of +/- 10 - 20% will not adversely affect the sound. Ported boxes must be fairly precise in volume and tuning. Consider also the fact that sealed boxes have very gentle roll-off characteristics after F3 at -12 dB/octave. Because ported system cut-off is a steep -24 dB/octave, often lower bass can be realized with a sealed design even if the ported F3 is lower. (Note: attenuation slopes after cutoffs are almost never exactly these values, and may be steeper or more gentle depending on alignments).
wow, i think you spent more time typing than reading.
let me sum this up for you.
Sealed designs have several advantages for the car. One is enclosure size, as optimum ported systems generally must be larger. Building an optimum ported enclosure for the home is easy, as you usually have more than enough space for that big box. If you try and design an "optimum" ported box for your car, chances are you will find out quickly that the size of the enclosure will be unacceptable. Most people value cargo space, and unless you are willing to sacrifice all or most of it, large drivers in ported enclosures are not an option. To achieve ported enclosures in vehicles, most designs call for a much smaller box than optimum. This has the end result of much worse transient response, a higher F3, and the potential to unload at low frequencies normally seen with demanding music. Ported systems behave much like a sealed enclosure if you make the box smaller, and you will find that a large peak will appear and grow in the response curve around Fb the smaller and smaller the enclosure becomes. This makes the system boomy, with that one note unmusical quality seen in so many systems today. A compromise ported enclosure may be more efficient than sealed, but you lose a lot in the way of quality.
With all the new "small box" drivers available today for sealed enclosures, very good performance can be achieved with minimal space used in the vehicle. A true optimum enclosure is a reality with a Qtc of 0.707, with superior transient response and a low F3. Cabin gain is also something to consider, and with the gentle roll-off characteristics of the sealed enclosure, cabin gain multiplication at the lowest frequencies becomes greater with these designs. This can be good or bad, depending on your viewpoint. Small sealed enclosures need more juice to achieve comparable SPL's to ported, so make sure you have enough amplifier for the task if you choose this route. I have yet to see true "small box" ported drivers comparable to those available for sealed enclosures, but they might be out there. A driver specially designed for high performance small ported enclosures for the automotive environment seems like a good idea. But if you have the room for a larger box, ported enclosures can certainly provide some very real performance advantages over sealed enclosures.
Designing and building speaker systems is fun and rewarding. Few hobbies offer the chance to combine both art and science into a project with the end result something that can be enjoyed daily for years. The age old question of which enclosure is best will continue to be asked by builders and designers, and like anything else the answer is "It Depends."
what its basicly telling you is that a good ported enclosure that wont ''unload'' on low frequencies is going to take up about half of your car, house speakers use this efficient desighn because there is enough room. you can use a sealed enclosure with its own less demanding specs and get prety close to the same sound with alot more diffrent brands and a better frequency responce with about half of the space.
The only thing this keeps on saying is ported boxes are big, blah blah blah. 2 cubes is easy to get out of cars for a single 12, tons of guys run 4 or 5 cubes easily for 2 12's.
Your post mentions the small sealed enclosures, but you need even more power to come close to the output of a ported box. It's not pretty close. 500 watts out of a sealed enclosure vs 500 watts out of a ported enclosure are like night and day.
Again too, the info you sent was written in 1997, and technology for speakers has come a long way since then.
To add to this. I don't believe that a good "SQ" box should exclude lower frequencies. Good luck finding a driver that will have an F3 below 40Hz in a sealed box.
The only positive I've ever seen from a sealed design (other than compactness at less loss of quality, IMO) is less delay, but thats really only a theoretical problem as I've never heard a half-well-designed system with a bad enough delay as to degrade sound accuracy.
well i didn't mean to start a big debate as to which is better sealed or ported(vented)
i just wanted to know what my dimensions for a sealed box for 1 of my 10 inch mtx sub would be.......
sooooooooo with that siad
I did some googling, for software cause i can be impatient...at times
I was able to calculate the size of a box (I think)
see what this sounds like
11.6139 inches in length = across the front of box from left to right
18.8145 inches in width = across the front from top to bottom
7.16907 inches in depth = across sides from front to back
at least thats what i gather from the box picture it showed me when i had it calculate it all..............
now those decimel points need to be made into fractions i guess so i can cut the amount of wood i need to the desired sizes i need to build a box...
kinda looks like it'll be 11.7 inches by 18.2 inches by 7.2 inches...
sound right?
I found & used a software called AJ Sealed designer
thats from inputting the parameters MTX provided me on the woofer...
what ya'll think?
MikeC!
91 sunbird Convertible
3.1 with an automatic
http://www.cardomain.com/ride/3038464
