Would you seal a ported sub for a small room?

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jarablue

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My svs pb 2000 pro sub is in a small room. I plugged it with the port plugs and changed it to sealed mode on my app. It sounds good but wondering if you guys keep your ported subs open in small rooms? Right now I enjoy it's performance and it is wicked good with what it needs to do.

Just wondering. Thanks!
 
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My svs pb 2000 pro sub is in a small room. I plugged it with the port plugs and changed it to sealed mode on my app. It sounds good but wondering if you guys keep your ported subs open in small rooms? Right now I enjoy it's performance and it is wicked good with what it needs to do.

Just wondering. Thanks!
A driver designed for a ported cabinet can lose more than a little low frequency response- some stop being a subwoofer. At that point, it's not worth using.

OTOH, you can seal it and if it works well enough for you, go with it.
 
My svs pb 2000 pro sub is in a small room. I plugged it with the port plugs and changed it to sealed mode on my app. It sounds good but wondering if you guys keep your ported subs open in small rooms? Right now I enjoy it's performance and it is wicked good with what it needs to do.

Just wondering. Thanks!

If you seal the port then the sub is misaligned. The box size for the same driver in a ported box or sealed box is different. The sealed box needs to be a lot smaller. Also most drivers have T/S parameter optimal for sealed or ported but not both. So leave the port open.
 
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If you seal the port then the sub is misaligned. The box size for the same driver in a ported box or sealed box is different. The sealed box needs to be a lot smaller. Also most drivers have T/S parameter optimal for sealed or ported but not both. So leave the port open.

The svs app for my sub can run it in sealed mode or ported mode. I put it in ported mode...heck with it!
 
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Don't believe everything a manufacturer tells you. That is nonsense, and totally impossible.

Well I trust svs to make a feature and stand by it. Or else they would get in trouble for it.

Anyways, back to ported mode it goes.
 
The svs app for my sub can run it in sealed mode or ported mode. I put it in ported mode...heck with it!
You still need to manually plug the ports for the two sealed modes, tho. Of course it doesn't make it both an ideal ported sub as well as "sealed" sub but could be useful options....
 
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You still need to manually plug the ports for the two sealed modes, tho. Of course it doesn't make it both an ideal ported sub as well as "sealed" sub but could be useful options....
Yeah SVS included the port plugs with the sub when I bought it. Works totally fine. Sealed and Ported mode is on the app.
 
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Don't believe everything a manufacturer tells you. That is nonsense, and totally impossible.

Well, I have designed a lot of speakers in my time. I can tell you the math is against SVS on this. The volume in the enclosure of a ported and sealed alignment are always markedly different. If you understand how speakers work, then you would understand that has to be so. So either the ported box alignment is wrong, the sealed is wrong or both are wrong. That is just the physical laws of the universe by which we are all bound.
 
I tried sealed in my room with a pb 1000 pro. Let's just say I have not done that again.
I found the sub lacking when I did.
 
Well, I have designed a lot of speakers in my time. I can tell you the math is against SVS on this. The volume in the enclosure of a ported and sealed alignment are always markedly different. If you understand how speakers work, then you would understand that has to be so. So either the ported box alignment is wrong, the sealed is wrong or both are wrong. That is just the physical laws of the universe by which we are all bound.
So you designed particularly speakers or subs or ? This use case isn't perhaps ideal, but neither are your speaker builds.
 
Well I trust svs to make a feature and stand by it. Or else they would get in trouble for it.

Anyways, back to ported mode it goes.

Look into enclosure design for low frequencies- the driver dictates the internal volume and if needed, the port tuning, which is based on diameter and length. If a port is used, its volume must be added to the enclosure's internal volume. Depending on the wants & needs of the system and the driver's T/S parameters like cone mass, QTs, VAS, etc, the internal volume determines the Q of the system. Close the port and that changes. Make a box smaller and the Q increases, make the box larger and the Q decreases. .707 is ideal WRT response without ringing- high Q creates a peak that can be obtrusive and if it's too high and its F3 clashes with the main speakers, it can be a 'one note wonder' all alone in the wilderness or it can cause constructive/destructive interference in the area where it overlaps with the main speaker's woofer response.

Unless SVS deals withall of this in a direct and distinct way, just shoving a piece of foam into the port isn't going to be the best way to deal with this. It can, however, slow the air movement without completely screwing up the Q but closing the port chops a good amount of response off of the low end.
 
Can I blast farts into the sub when it's in sealed mode to get more oomph out of it? I know ported gives more oomph but my farts after a taco bell night is something to behold.

Maybe?

All seriousness, thanks for the help. I'll keep it in ported mode from now on. Jambumpa Jabamky out.
 
In the sense that most simply aren't going to build your designs. You have specific goals and seem to satisfy yourself with your builds, just may not be ideal for most

That is one of the huge points of DIY, you can design gear free of marketing considerations. They never sold any other pairs of the Maida Vale BBC monitors either. That was not the point of them.
 
I’m in a small room too and ended up sealing my PB-2000 Pro—tightened the bass and blended better overall. If it sounds good to you, I say trust your ears and enjoy!

 
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I’m in a small room too and ended up sealing my PB-2000 Pro—tightened the bass and blended better overall. If it sounds good to you, I say trust your ears and enjoy!

Usually a bad idea. You lose the low bass and the driver is misaligned as it is in too large a box.
 

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