Can a vented sub be stuffed ?

Hi,

I would like to know whether it is possible to damp a vented sub?
I have a 12" sub driver with low xmax. Sealed alignment does not have the extension (simulated by sealed.xls available on the net). Vented requires a huge box (simulated by ported.xls available on the net). Can I stuff the cabinet to have something between the two and yet get away with a small enclosure.

Thanks in advance,
Goldy
 
Yes you can stuff the cabinet to get a smaller box. You'll lose efficiency and it'll be hard to tune it right because you can't use normal software to tune a stuffed vented box. You have to do it with a multimeter and a bit of trial and error.

In the end you get a vented box with efficiency lower than a sealed box, but frequency response is flat down low. It depends on what do you want, if loudness is not required, it will be perfect.
 
Yes you can stuff the cabinet to get a smaller box
I'm sure you ment bigger ;)

@Goldy: If you stuff a vented box, take care not to block the air-flow from the speaker to the vents. Also the vent itself shouldn't be stuffed. This way you'll get up to about 15%-20% more volume (also called virtual volume).
Stuffing the ports will make it sound and act more like an closed box (not necessarily a bad thing)

By making a bassreflex bigger (with stuffing) after it's tuned/made, you'll also tune it lower. That's (the 2 reasons) why you'll get more low end extension. However as a trade-off the gain by the port becomes less. Also the groupdelay will rise and if you have problems with portnoise, the problem gets slightly bigger.

However it isn't as much as a different as some post/people would make you believe.
Just make a cabinet according to what you like and afterward do some fine-tuning with stuffing. Personally I would just use my ears and focus on a good sound rather than anything else.

Stuffing also helps against standing waves inside the cab and can remove some of the "boxiness" from the sound.

If you haven't designed the cab yet, you can make the effective volume about 10% smaller and re-gain it with stuffing. Tho I rather would only apply it afterward in a BR.

A lot of the soundchanges you're hearing after the stuffing can't be simulated with the software you're using (or going to use)anyway. Don't take it to heavily.

Mvg Johan
 
Interesting theory, could you elaborate?

Quite some people (including the writer from the article/link above) would disagree, at least partially.
Considering the theory behind why stuffing works, even one fiber would have effect (very little but effect none other the less).

So why should it be completely filled?

Mvg Johan
 
Well, that is a respected source. It looks to me that he fully stuffed the vented box, but just used different levels of density. This goes against all the wisdom I have read on vented boxes. The air must be free to move around so that the Helmholtz resonator can function as intended. Typically, fully stuffed vented enclosures tend to act more like a halfway between sealed and vented, rather than a vented of larger volume. I'm sure Ql would be quite drastically different between a stuffed and unstuffed vented box.