SQ sealed vs SQ ported?

[Team_DC-Derrick]

please explain how then? unless its a bandpass i havent seen it done

[skittlesRgood]

by tuning stupid low and losing output. so itll be quieter and almost pointless. its just a general rule of thumb. if hes asking a question like this do you really think he will know how to build the perfect ported box? i gave an answer that i feel best matches his audio level.

lets see your boxes if you know so much.

[Dan208]

I know that you get more output from a ported box, I was just curious because I've never seen box recommendations like this. They have sealed SQ-.5, ported SQ-.65 and SPL ported 1.25.

Like I said, I was wondering about it because this is the first time I've ever seen box specs listed this way.

[Corey]

just like army guy posted. sealed box has a flat response curve. a ported box will peak around the boxes tuning. ive built many of both and you can hear a difference.

Once a ported box is put inside a car it could peak at something entirely different, its not going to be exactly what you tune the box to.

[keepinitloud]

Once a ported box is put inside a car it could peak at something entirely different, its not going to be exactly what you tune the box to.

you must be refering to the resonent frequency of the vehicle and that does play a part in the final outcome of the install but I have had sealed boxes and ran ported ones and you can definetly tell the difference between them

[skittlesRgood]

Once a ported box is put inside a car it could peak at something entirely different, its not going to be exactly what you tune the box to.

i didnt say "exactly" i said "around". but thats not even the point of what i was saying. im really tired of everyone nit picking anything they want just to show people that they know something even when its not on the subject of the thread.

[Dan208]

Something else that I found in the manual.

Sealed:

Power Handling-Good at all frequencies

Linearity-Excellent

Dynamic Performance-Excellent

Efficiency-Good

Subsonic Output-Excellent

Midbass Output-Excellent

Enclosure Size-Small

Ported:

Power Handling-Good above tuning frequency

Linearity-Good

Dynamic Performance-Good

Efficiency-Very Good

Subsonic Output-Good

Midbass Output-Very Good

Enclosure Size-Medium

So my question is, are these subs better suited for sealed boxes? Notes: I'm not interested in numbers. I wouldn't mind getting metered just for shits and giggles, but my main goal is for a loud, good sounding daily driver. Also, since my vehicle is the "family truckster", I can't afford to take up the entire back, which is why I was only asking about the SQ sealed and SQ ported box sizes.

[Team_DC-Derrick]

sealed will sound better for all around frequency's like 20hz to 120 hz where as a ported box tends to drop off 10hz ish above the tuning of the box, for straight SQ, sealed will be better... in my opinion

[Ben Building]

A speaker has damping parameters (numbers) like the Qes (Electrical damping), Qms (Mechanical damping), and Qts (Total damping). Once you put the woofer inside a acoustic suspension (sealed) box, the Qts will change to a larger number called the Qtc (enclosed damping). These damping parameters are just a way of saying how the cone motion is controlled. In a bigger sealed box, there is more air inside to support the cone motion. A huge volume of air has much less resistance to being compressed with a certain size piston (your sub), so the Qtc total damping will not rise as much inside a large sealed box. In a small sealed box, the qtc will rise much more.

Typically, guys shoot for a Qtc of about .707 for SQ. This allows the woofer to have a maximally flat response and as much low-bass extension as the sub will allow in a sealed box. A Qtc of .707 is called "critically damped" because, after that, making the box larger will have diminishing returns. The output will be much less for hardly any additonal low-end extension. A critically damped sealed box can be almost a big as a ported box, but it won't be nearly as loud. Depending on the sub, however, it will be deeper and more controlled.

In my own personal experience, building for a Qtc of around .9 sounds great once inside the vehicle. Some guys even go a little higher on the enclosed damping with 1 - 1.3. That provides for additional (more peaky) output and greater power handling than a .7 Qtc.

In a sealed box, the Qtc formula is:

Qtc = Qts * [ ( Vas / Vb ) + 1 ]1/2

[kx519]

Every sealed box I've built has had a tighter, cleaner sound than a ported box.

Just seal it up really good or it will sound like poo.

Air leaks are way more noticeable in a sealed enclosure.