[SonomaComa]

What do the Ports inside of Subwoofer look like? Is it just a hole put right into the side of the box, or is there a tube that runs deeper into the box connected to the hole?
What would it be like if you drilled your own hole or holes into a sealed box? Then you could just drill little 3/4" to 2" holes to achieve the desire3d results. That way you could get just that little edge for deeper tones and keep the tight sounds out of a sealed box and let the Driver "breath" a little bit.
Has anybody here ever done that? Or is that just the dumbest idea ever?
http://www.svsound.com/subwoofers

 

[shadyJ]

Do NOT drill holes in your box or attempt to add ports. The port size has to be carefully balanced with the driver parameters, cabinet volume, amplifier settings, port width, and port length. IF you know the parameters of your driver, and IF they are suitable for a ported enclosure, than you can make a vented cabinet for it with various tuning points. It sounds like you will need to do a lot of reading about subwoofer enclosure design before you reach that point.

 

[Red99]

You can not convert a sealed to a ported. You would be best to sell the sealed and buy a ported, or add more sealed subs.

You can plug the port on some ported subs to make it behave like a sealed. But even that isn't really recommended by some manufacturers.

I wouldn't mix (sealed with ported subs) either, even though some people has done it with great success ,its not recommended.

You might be able to buy a DIY ported kit and put your driver in it. Be best to go to the DIY section for that. And they can maybe tell you if your driver is a candidate for that. DIY ported boxes are not very expensive.

 

[Bill Fitzmaurice]

You can not convert a sealed to a ported.

Actually, you can, if you're trained in loudspeaker design and have software modeled the driver and box to see what the outcome would be. Catch-22 in this case would be that if you're trained in loudspeaker design and have software modeled the driver and box you wouldn't be asking the question in the first place.

 

[Red99]

If that is the case then why aren't there any ported box's as small as sealed subs?

 

[highfigh]

If that is the case then why aren't there any ported box's as small as sealed subs?

Because the volume of the port must be included, the driver is different and because you can't argue with physics.

Ever blow across the mouth of a bottle? That's how a port works. The length & diameter determine the pitch (frequency) and the speed of the wind across the mouth, along with the port's dimensions determine the volume level.

The sealed box acts like a spring, to control the movement of the cone. Remove the driver from the box and play the same music- you'll see the cone move far more than it usually does and it may be damaged by the excessive excursion.

 

[Red99]

Yeah I know the difference between a sealed and ported and how they work. I don't think you understood my statement.

 

[Red99]

Because the volume of the port must be included, the driver is different and because you can't argue with physics.

Well if I cant argue with Physics, then can I argue with you? Thats true on some drivers. But there is also some that can run ported/vented or sealed. Example, look at SVS ported subs that comes with port plugs. Or this review from Databass for the 21SW152-4 driver that Ricci tested in both ported and sealed.

This system is a single 21SW152-4 in the 4.5 cubic foot 23x23x20” sealed test enclosure. Again the big B&C driver reinforces it’s strengths as mechanical ruggedness, sensitivity, clean upper bass response, low distortion and high thermal power handling. This driver is intended to be used in high power bandwidth limited, vented, horn and band pass devices and is more at home there but a good driver is a good driver and it can work well in a small sealed enclosure as well with some signal shaping to shelve down the top end some. In a direct radiating system such as this it could easily be used up as high as 400Hz if needed. The SD of the 21” cone helps provide decent low bass output despite the modest xmax rating though it won’t compete with the top extra long stroke drivers in that department. Once the bass is up into the more typical music range the output peaks available with even a modest amplifier are generous to say the least.

Or the people in the DIY for the UXL group buy. Some are building ported, and some are building sealed with the same driver.

But even in these cases, I would "Never" try to convert a sealed to ported. Or use the driver without consulting with the manufacturer.