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Since the "other" thread was closed to I suppose getting off topic (yea...) I'll start up a new thread here that is a bit more specific.

In relation to sound quality.. what I've found is a really good, very effeciant ported box actually yields *much* better SQ than a simple sealed box. Why? Because the woofer might only have to move 2-3mm to provide ample bass, even on the highway.

Thats less work for more sound.. which allows for much more amplifier headroom, easier on the electrical system (...), and much easier on the woofer. At the same time, it saves you $ by keeping you from "needing" more woofer and more power. Saves $ from keeping you from killing your alt (...) and keeps you from needing to upgrade everything. And of course, when you wanna get loud, there you are :)

What do you SQ guys think? From my experience a *well* built ported box can really boost SQ, whether it be from horrible to decent, or from alright to excellent... I have yet to make a ported box geared towards "SQ" (they always get loud too) that didn't sound better than the woofer did sealed... but on that same note, I'm not really an SQ head and if you can cite specific examples to the contrary, please do :) . I can see perhaps a woofer like a brahma, which sounds good throughout its range, being a good sealed box candidate?

Could there possibly be any benifits to running a very ineffeciant setup? I really dont see any beyond saying you have more woofer and more amp.

Generally quiet people tend to say they are SQ, when sometimes the SPL guys only have to turn it down to sound good :)

Depends on the subwoofer used of course, but I agree with you in many accounts. It's all in what your goals are. Most car audio subwoofers are either a long gap/long coil design or a short gap/long coil design, which typically results in a parabolic BL curve over the excursion range, higher excursions equal higher distortion with those designs in most cases. The majority of car audio subs are leaning toward ported and small sealed box designs, in both their motor design and their suspension design, because people like the flexibility. If you want low distortion, low excursion, and clean output, ported can outdo sealed IMO, and ported is capable of much less distortion than sealed at high volumes in most cases, that is of course assuming that you choose to tune the box low enough to retain musicality without risking overexcursion and at the same time limit the sub's excursion over the entire excursion range. Sealed wins if your goals are to have better transient response, group delay, and acoustic phase, but in a car a difference in transient response is much more difficult to notice than having high distortion at high volumes, and only a few subs can have very high output in a sealed box and sound great at the same time. Sealed also has a more natural frequency response due to the rolloff of it combined with the cabin gain of a vehicle, ported you'll need an EQ to flatten the hump out. Some people see this as a benefit since you can EQ out the hump in frequency response when using ported boxes and strain the sub even less. The reason ported gets it's bad reputation is because a good ported box is more difficult to design and get great results with, plus the fact that many of the uneducated base their opinions on an el cheapo prefab at Best Buy. "Oh, ported boxes suck for SQ, they are so boomy!" is a typical response you hear, but they usually base that upon an extremely small box tuned in the 40s. If ported were so bad you wouldn't see $20,000 home audio systems using them. With subs like the Adire Brahma you can have good SQL in a sealed box, but there are few subs that have as wide a BL curve as a Brahma. Mainly XBL^2 drivers and underhung units are the ones that will deliver good SQL in a sealed box. Plus the fact that the suspension of subs like the Brahma leans itself more to sealed boxes than ported.

Jonathan wrote:The reason ported gets it's bad reputation is because a good ported box is more difficult to design and get great results with, plus the fact that many of the uneducated base their opinions on an el cheapo prefab at Best Buy. "Oh, ported boxes suck for SQ, they are so boomy!" is a typical response you hear, but they usually base that upon an extremely small box tuned in the 40s.

Lol... thats what people refer to when they tell me "well i HAD a ported box and I didnt like it as much as sealed!!!".

Prefab ported boxes are a sham...

The problem with the RIGHT ported box is that they can be 2-3x as large as a prefab sealed/ported. That means you cant fit as much cone area... which doesn't sound good to the typicap noob when they are deciding on what to get. But the truth is... if you know what your doing, any number of sealed woofers couldnt compare to a ported box's performance.

If ported were so bad you wouldn't see $20,000 home audio systems using them. With subs like the Adire Brahma you can have good SQL in a sealed box, but there are few subs that have as wide a BL curve as a Brahma. Mainly XBL^2 drivers and underhung units are the ones that will deliver good SQL in a sealed box. Plus the fact that the suspension of subs like the Brahma leans itself more to sealed boxes than ported.

Things like the brahma and w7 are the only subs that I can say I liked the way they sounded sealed.

The ascendant atlas also sounded pretty good sealed... and even better in a small low tuned box.

Its a great debate - ported vs sealed... and you really have to go application by application to find out whats best.

If you are forced to run a small sized box, to the point of you cant even properly port a single 8" driver... in that case sealed is a better alternative to running puny port area to try to get a low tune in a small box - which is the case with even alot of "experienced" box builders.

You made valid points, but I don't think I'd say ported is good for SQ per se.. it will however, as you said, give more output with less power, and actually tuned low, the box will peak right where all that nice deep bass is, which is what most people really want anyway, even if they hate to admit it, or don't realize it.
As for actual SQ, while distortion may be lower with a vented enclosuure, for strictly "SQ" purposes, sealed will give a flat response, with less group delay and no port coloration. This is why ideally, AP enclosures work so well in a car for SQ. They give the flat response of a large sealed enclosure, but they improve mechanical power handling, filter high frequency information, and reduce 2nd and 3rd order harmonics.
Like everything though, there's always a drawback. In this case, an AP box eats power to reach acceptable volumes, which is what your ported enclosure will correct.

Without getting into more esoteric designs like bi-chambered aperiodic enclosures (ABC boxes) I agree ported is the easiest way to use the least amount of power and get good sound with good volume levels. Purely based on SQ though, the ported box does have some drawbacks, but honestly unless you're worried about an RTA curve, or you really know what a flat response sounds like and you're sure it's what you want, ported boxes usually give a person the best results in a car for overall balance between efficiency, SQ, etc. I suggest them to just about anybody who doesn't know exactly what he or she wants from teh start.

I'm fairly certain you can get a flat response with a ported box?

Would probably just take more work and some EQ work.

Why does transient response suffer in a ported box? Can this generalization be made across the board?

"Why does transient response suffer in a ported box? Can this generalization be made across the board?"

The increased mechanical control of the enclosure, due to the port, is what makes the response suffer. The generalization can be made across the board for any ported box, but good designs minimize problems. The tuning and enclosure itself will take an effect on where this occurs at and how negatively it affects it. After the port becomes inactive (too slow to react to changes in woofer movement, aka higher frequencies) then the enclosure will perform nearly the same as a large sealed. Group delay (which corresponds to transient response) can be minimized and be below what is considered to be the threshold of human hearing (many consider that to be 20 milliseconds, others consider it 10ms), but of course that is a debatable issue and the answer is usually left as ported simply having worse transient response.

You can get a flat response ported via EQing, but it's more difficult in a car simply because of the cabin gain. In home audio, ported can have a flatter response than sealed because you don't have a lot of room gain, ported has a lower system fs than sealed when tuned to do so. In a car, sealed, AP and infinite baffle offer the flattest response you can get. Remember that EQing adds phase shifts and complicates the load presented to the amplifier since you are cutting and boosting. The best EQing is none at all, IMO the best systems offer a relatively flat response from the get-go, and only minor tweaks are needed to get it right. AP membranes also help flatten the impedance curve presented to an amplifier, ensuring a consistent load and a predictable frequency response. The purist audiophile isn't going to choose ported, for the same reason that they wouldn't use high order crossovers on speakers. They are focused on good phase alignment and transient response, as well as a flat, predictable frequency response without a lot of tuning and extras to get it. That is where sealed, AP, or infinite baffle excel at. Most people in the car audio hobby want a loud system that sounds good, which is why ported boxes and high order crossovers give good results. That's also why I recommend ported to those types of people, because of the fact that sealed and AP, while they offer the best SQ IMO, don't do as well at high volumes. If you choose a sealed box and have nothing but high volumes in mind, you're likely going to hear a lot of distortion due to the higher excursions. IMO it is much more noticeable than a difference in transient response. Most top end SQ equipment isn't really that loud (especially components) because the drivers are less efficient due to the damping of the drivers, materials chosen, suspension used, etc. Being more of a purist SQ guy and also because of space restrictions, I use sealed, but I've used ported before for certain applications and have gotten good results with both. It's all about matching the horse to the course, you have to know your goals.

Jonathan pretty much summed it up before I got back here.
you can get a fairly flat response from a ported box, but by the time you do that, you're adding phase shift and delay from all of the EQing, and you're not gaining any of the advantages of going ported to begin with, so you may as well go sealed at that point.
I like ported enclosures. I use them a lot. They just aren't the ideal solution for actual accuracy (transparent response) in a car setting. This raelly doesn't matter to 99% of people though, since most folks don't want a flat response anyway. They want to crank the bass, have crisp treble, and acceptable vocal ranges.
ported can offer lower distortion with higher group delay and slower transiet response, but how much most people will notice this is really up for debate.

I would think group delay and such could be addressed by a smaller sized lower tuned ported box. Its difficult to have enough port area in a small box to make it useful... what you end up with is pretty much a transmission line.

Some subs also dont take very well to smaller sized boxes - but an "sq" woofer definitely should.

I can't really see flattening out impedence as mattering all that much, effeciancy at different frequencies will be different anyway.

there is nothing wrong with a prefab box if its built good like a subzone box and made to the specs of the sub. and they save you alot of time. and i love sealed boxes but thats my opinion and taste its alot easier to get great sq out of the sub and they still get plenty loud for most people like an elevation audio pro 12 will get louder than alot of people want and sound very good.

yea, but a prefab box for a specific sub isn't really a "prefab".

That being said... nothing holds a candle to a custom box... and those subzone boxes arent cheap.