Can somone please explain...

[95stroked1500 10+ year member]

it depends on sub design. and there are a lot of trade off's involved in sub design.

one reason for degraded transience with a large box, is less restorative force from the box itself, acting on the speaker.

take a sub that is built upon being in ported box and has 3 or 4 spiders. in a moderate sized ported, it can still have better snap than many other subs have in a sealed box.

there can be many other factors also. this is just one more angle.

 

[Thnking 10+ year member]

I understand by tuning Low with a ported box subs should maintain more SQ right? then how come Ive heard that for rock music tuning high is best? //content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif
But what is the relationship between ported box size and SQ, am I right in thinking smaller boxes would have tighter responce and larger boxes more output with less QTC?

It's simply because rock music doesn't typically contain frequencies as low as rap does. It's a stereotype, and obviously not the case for all types of music.

As box size is increased QTC decreases. Decreasing QTC means more damping. Also, if the system resonance is kept at the same frequency while box size is increased, efficiency increases.

Properly ported boxes aren't boomy or slow. You need to design size and tuning frequency of the box to align the port response with the subwoofer's response.

 

[dirthog 10+ year member]

How would polyfill effect everything? I am thinking about building another box and adding some to the sub.

 

[Toxic Tuan 10+ year member]

The most important factor has yet to be mentioned. Transient Response in terms of Group Delay. Look at the box's group delay. The lower the better. Try to keep group delay under 24 ms...18ms is even better...and it'll be a great box regardless of the music it plays. This will give you the most accurate reponse and the transition from one note to another will be fast and precise.

tuan

 

[Immacomputer 10+ year member]

People usually assume ported boxes are "slow" because they will usually put the driver in an enclosure with too high of a group delay. Usually the enclosures are oversized, which causes a higher group delay and can add to the "boomy" sound people often refer to.