Can you "dampen" the thump from kicks on a ported sub?

0Hz

Active Member
I've rewritten this 3 or 4 times so as not to look like a complete retard, so here goes...

Probably a dumb question, and I'd have bought a sealed one if I was smart and found one in my price range and asked for brand advice... But let's set that side. Do ports even come into the equation here? lol...

Would stuffing the port have any positive effect if I were looking to dampen the thumpiness of kick drum and those related frequencies? Right now they overpower the frequencies I actually want to hear IMHO. They just come through louder which is not good in a house with sound that carries and especially for late night listening.

The sub in question is a Polk PSW10, front firing and front port. It's not sitting in a corner, but close enough (~4 feet from wall to its left, ~2 feet from wall to its rear, computer / desk to its right).

I can DSP computer audio to somewhat deal with that, but I've also got the radio and vinyl to deal with at the moment.

Would I be better served raising the crossover and lowering the subwoofer volume? I am positing here that even though I am lowering the volume to bring the kick range frequencies into line, the other frequencies on the high end of the crossover will also still come out louder at lower volume (due to woofer size) than if I were relying on my speakers to produce those frequencies as well.

I don't like the idea (due to its size) but I thought about possibly just keeping it under my desk to keep it out of any corners. But then again its surrounded on 3 sides. no matter where it goes in the room its going to have close distance reflection points....

Ultimately I plan on just buying a miniDSP and dealing with things that way. But for now just looking for a short term solution. A dedicated audio room isn't an option, I can't really fit tall / floor standers in this area but I had the floor space for the sub.
 
I’ve never tried sealing a ported sub , have you retried room placement? Some spots are boomier , are you using it for home theater?
 
Not really for home theater. But I do watch media on my PC. Youtube, Amazon, etc. That stuff isn't so bad so far. It's really the kick drums in music and stuff that needs to get under control for now.

The only other place I can move it too is the other side of the desk, but in terms of things immediately close to it on all 3 sides, it would be even more cramped.. like being under the desk. So I'm kinda feeling "meh" about moving it at this point.

These are really my options in terms of realistic open space.

Sorry for the mess....lol

IMG_0075[1].JPG IMG_0076[1].JPG IMG_0077[1].JPG
 
It's a boomy cheap sub, period. Best thing you can do is replace it.
This. It's not necessarily due to the fact that it's ported - there are plenty of good subwoofers and speakers that are ported and not boomy.

In the past there were a few speakers that came with a piece of foam to plug one or both ports, but they were designed that way from the start. Since you've already got the sub, it couldn't hurt to try.
 
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IME many times a subwoofer sounds overly boomy because the crossover frequency is to high and/or it's turned up to loud. If you can tell there is a subwoofer it's not dialed in properly. When it is, the only time you'll know there is a sub is when you turn it off.

While that Polk SW is no JL or Velodyne it can sound pretty decent when set up properly.

Anyone who thinks a ported sub can't sound as good as a sealed one please check out the Wilson Thor's Hammer. For one with real world pricing check out Hsu Research.
 
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I've rewritten this 3 or 4 times so as not to look like a complete retard, so here goes...

Probably a dumb question, and I'd have bought a sealed one if I was smart and found one in my price range and asked for brand advice... But let's set that side. Do ports even come into the equation here? lol...

Would stuffing the port have any positive effect if I were looking to dampen the thumpiness of kick drum and those related frequencies? Right now they overpower the frequencies I actually want to hear IMHO. They just come through louder which is not good in a house with sound that carries and especially for late night listening.

The sub in question is a Polk PSW10, front firing and front port. It's not sitting in a corner, but close enough (~4 feet from wall to its left, ~2 feet from wall to its rear, computer / desk to its right).

I can DSP computer audio to somewhat deal with that, but I've also got the radio and vinyl to deal with at the moment.

Would I be better served raising the crossover and lowering the subwoofer volume? I am positing here that even though I am lowering the volume to bring the kick range frequencies into line, the other frequencies on the high end of the crossover will also still come out louder at lower volume (due to woofer size) than if I were relying on my speakers to produce those frequencies as well.

I don't like the idea (due to its size) but I thought about possibly just keeping it under my desk to keep it out of any corners. But then again its surrounded on 3 sides. no matter where it goes in the room its going to have close distance reflection points....

Ultimately I plan on just buying a miniDSP and dealing with things that way. But for now just looking for a short term solution. A dedicated audio room isn't an option, I can't really fit tall / floor standers in this area but I had the floor space for the sub.


OP,

you will want to stuff the port with foam.



Cut out a strip, and roll it up in the diameter of the port, you may not want to completely seal the port. This will slow the airflow, yet still allow it to move. This will greatly lessen the thud or boomy loose base you are hearing. Tinker with it, add or remove foam for tuning.

Hope this helps you, let me know if this works out for you.

Kind Regards,
John
 
Would I be better served raising the crossover and lowering the subwoofer volume?
I'm with Joe - more likely you need to lower the low pass setting so that the sub is not sharing the "thump" region with the mains. They are designed to supplement the mains, not thicken what they are already doing.

I use a pair of Eosone subs (designed by Arnie Nudell using Polk drivers) and have them set at 50 hz and used basic measurements to determine the optimum blend level with the mains.

Takes lots of experimentation and ideally some level of measurements. It doesn't have to get complex though.
 
Not really for home theater. But I do watch media on my PC. Youtube, Amazon, etc. That stuff isn't so bad so far. It's really the kick drums in music and stuff that needs to get under control for now.

The only other place I can move it too is the other side of the desk, but in terms of things immediately close to it on all 3 sides, it would be even more cramped.. like being under the desk. So I'm kinda feeling "meh" about moving it at this point.

These are really my options in terms of realistic open space.

Sorry for the mess....lol

View attachment 1308307 View attachment 1308308 View attachment 1308309
Well if you get a high powered sealed sub like all that clutter needs to be far away enough or it will rattle it all.
Quality ported sub or a high powered sealed one is the way to go. Some brands allow you to plug the ports or run them sealed maybe go for this .
A sub is going to be boomy if it’s lower end no matter what my klh gave me headaches as a primary sub It runs as a secondary sub now playing back up bass behind my tv stand.
Take a look at this sub it subwoofer my wishlist now !!!
https://www.monoprice.com/product?p_id=24457
 
For the record:

Sealed subs are not better than ported. Subs are not fast slow or anything in between. They are either good or bad. Mostly, they're not setup properly.

It's all in how the sub is implemented and that depends completely on how it's set up.

If you can tell a sub is in use it's not set up properly. You should only know a sub is in use when you turn it off. The shrinking of the sound stage and the loss of foundation sounds should be immediately obvious.
 
OP,

you will want to stuff the port with foam.



Cut out a strip, and roll it up in the diameter of the port, you may not want to completely seal the port. This will slow the airflow, yet still allow it to move. This will greatly lessen the thud or boomy loose base you are hearing. Tinker with it, add or remove foam for tuning.

Hope this helps you, let me know if this works out for you.

Kind Regards,
John

Putting anything like that in the port will raise the effective mass of the port and completely destroy the alignment. The resulting sound will totally suck. It is something else going on.
 
Sorry if that came across as a putdown, which I did not at all intend. There are a surprising number of people who claim to be experts on speaker technology that do not understand bass reflex design.

Not at all, I'm no expert, just a hobby for me. As stated in my original post, the foam will slow the air movement. This will dampen the thud sound he is speaking of.

As for "bass reflex design" , placement is key. In this situation it is what it is.

I don't think it would "totally suck" as you say. There are speakers designed with removable foam blocks for this exact reason.

My DM-640s had foam and adjustable ports...

I would also use foam on my snell towers, this would help with booming bass in a small space. The idea is not to stop the air, but to slow it just enough to dampen it.

But maybe for a sub it's different. Im not a fan of subs as is so I say again.. what do I know :)
 
Its the design of the sub not whether its ported or not. A lot of ported subs are boomy due to mfr using a driver with to high of qts. For a decent ported sub the driver should have a qts of .5 or lower.
 
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