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

[Imprecise]

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

In those speakers with removable foam plugs, the plugs are designed to provide different alignments.They are not random chunks of foam shoved in the port. What you were doing on the Snell's was preventing the air from sloshing back and forth in the port, creating a whooshing sound. The result of this without a corresponding adjustment in overall alignment would probably be a premature rolloff of the deep bass which would prevent the room geometry related booming by eliminating the frequencies responsible for the booming. This would also significantly modify the frequency response in the deep bass.

 

[mhardy6647]

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.

I suspect it's usually a deliberate choice of driver & enclosure to result in Qtc >1.

 

[Imprecise]

I suspect it's usually a deliberate choice of driver & enclosure to result in Qtc >1.

Qtc > 1 gives higher efficiency which means a smaller box size can be used. If carried too far, transient response gets muddy and frequency response quite poor. The classic 'ideal' is good old radical 2 over 2 = 0.707.

 

[0Hz]

Wow nice can of worms I opened huh....

I agree with a lot of the points here, there are many angles for me to investigate. I think part of the problem is I likely want/need speakers with better mid-range drivers / design to help with some of the "low but not that low" frequencies that I like to hear.
I suspected some of it is room placement that I need to try and experiment with, and I suspect that also some of it may be finding the right crossover setting. I did turn the crossover down. I think it maybe helped a little, but not quite in the way I would have expected. I still have thumpy kicks, but then I feel like I maybe lose a little of those slightly higher frequencies I actually want to hear.

It's very unnerving knowing you can sit in a live performance with perfectly balanced bass that you can feel in the air just as much as you hear it, but you can't even come close to that at home (gotta invest serious $$ for that). Granted I'm not looking for something that reverberates the carbonation out of my soda. Just something balanced, where the kicks don't feel overbearing.

I suspect room placement, and ultimately, some EQ via a DSP of some sort will get me what I am looking for, on my budget. I actually have what I need to route my analog audio through my PC and run DSP on it, so I can always experiment with that, and also with existing digital audio files.

Right now where I am at is, the crossover is set somewhere a smidge off the 80hz line (poor labeling, its 80, 100, 160 in 3 chunks....) and the volume more or less where I had it before. Maybe a touch increased. The thuds are somewhat subdued now, but to really hear some of the reinforced frequencies I was looking for I more or less have to play musical chairs around the room, or stand close to/over the subwoofer.

I haven't tested it with any of my YM2612 based vinyl yet, which really can have some thumping bass and drums, but PC audio is alright, although still a little "thin" as its always been.

I'm trying to avoid abusing the tone control on my SX-636 to crank the bass up (which helps with the speakers themselves) although I wonder again if maybe doing that, and then keeping the volume of the sub much lower might actually work out.

I'll try it sometime when people aren't around to get annoyed I guess.

I appreciate all your responses. But that math looking chart stuff is over my head

 

[0Hz]

Also to be fair, I think a large part of my problem is I listen to a lot of different audio styles from a lot of different sources, sometimes even when "lossless" of varying quality level in terms of mastering, etc.

I mean I've got a track going right now that I ripped myself years ago from a Playstation game and I can clearly hear the kind of tones I'm looking for in general. But then I could put on something from Alan Parsons and .... well, I'm sure it sounds better when you turn it up but at low levels that oomph just isn't there the same way it might be with something else. Sometimes that's intentional, but its lacking in a way that makes you psychologically go "damn this should really sound better than it does right now".

Maybe I'm just weird

 

[mhardy6647]

I appreciate all your responses. But that math looking chart stuff is over my head

What, this?

easy; frequency response on the bottom axis, output level (think of SPL, in dB) on the left axis.

Qtc is one of the parameters describing loudspeaker performance (total loudspeaker system "Q", or "quality factor", from the Thiele-Small model, which is kind of built around resonance behavior)

Qtc = 0.707 = "optimal" damping -- flattest, most extended bass response.

Qtc < 0.707 = "overdamped" (rolled off bass)

Qtc > 0.707 = "underdamped" less extended bass response with more or less of a peak at higher "midbass" frequencies: thumpa-thumpa-thumpa.

Don't be afraid of this stuff.

PS it's damping, not dampening. Water or other liquid is required for dampening, and loudspeakers generally don't like water.

 

[0Hz]

I kinda get it. I just never know how to read those things unless it gets explained to me..

Oh - so I was watching youtubes last night and I think it was some REL videos about subwoofer integration and placement, etc. They mentioned something I had never seen or heard of before, they put the sub in a corner (not all the way) but then aligned the driver on a diagonol line through the room to the opposite corner. I think I might try that for shits n giggles sometime. I just have to clear out this one corner...

Any of you guys ever try this arrangement? is it a REL only thing their subs are designed for?

 

[jazzmans]

Also to be fair, I think a large part of my problem is I listen to a lot of different audio styles from a lot of different sources, sometimes even when "lossless" of varying quality level in terms of mastering, etc.

I mean I've got a track going right now that I ripped myself years ago from a Playstation game and I can clearly hear the kind of tones I'm looking for in general. But then I could put on something from Alan Parsons and .... well, I'm sure it sounds better when you turn it up but at low levels that oomph just isn't there the same way it might be with something else. Sometimes that's intentional, but its lacking in a way that makes you psychologically go "damn this should really sound better than it does right now".

Maybe I'm just weird

most of the Alan Parsons Project albums were very 'thin', especially Pyramid, Eve,
Stereotomy. So, you will find, the higher up the chain you go with gear, the MORE these differences in the recordings come out, not the less. It can be frustrating.

Compare the MoFi cd of 'Tales of Mystery and Imagination" to the 1987 remaster/rerecording, and it's obvious.... I waited So long for that to be released on CD, and they had to butcher it. I was so upset after that wait. Thank DoG for the MoFi release!

 

[Grenadeslio]

Have tried this before, after much experimentation the best thing I found are these, if your sub has dual ports you'll need two. The wedge shape works perfect, just put the bottom of the cup into the port and push it in to wedge it tight.

 

[0Hz]

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.

most of the Alan Parsons Project albums were very 'thin', especially Pyramid, Eve,
Stereotomy. So, you will find, the higher up the chain you go with gear, the MORE these differences in the recordings come out, not the less. It can be frustrating.

Compare the MoFi cd of 'Tales of Mystery and Imagination" to the 1987 remaster/rerecording, and it's obvious.... I waited So long for that to be released on CD, and they had to butcher it. I was so upset after that wait. Thank DoG for the MoFi release!

haha I am the complete opposite. I grew up hearing the 1987 release my dad got on CD. I actually picked up a bunch of AP vinyl on ebay when I first got my turntable and got the original Tales' Album and was like "wait....wtf where is Orson Welles" and my dad is like "oh I listened to this all the time in college I actually prefer this version".... Meanwhile I hunted for months on ebay for a vinyl pressing of the 1987 album I was convinced didn't exist and then found one for sale in Germany.

 

[mhardy6647]

I kinda get it. I just never know how to read those things unless it gets explained to me..

Oh - so I was watching youtubes last night and I think it was some REL videos about subwoofer integration and placement, etc. They mentioned something I had never seen or heard of before, they put the sub in a corner (not all the way) but then aligned the driver on a diagonol line through the room to the opposite corner. I think I might try that for shits n giggles sometime. I just have to clear out this one corner...

Any of you guys ever try this arrangement? is it a REL only thing their subs are designed for?

That's a time honored way to "make" a bass corner horn. Col. Paul W. Klipsch, e.g., was a big fan of using the corners of a room to expand a horn (and thus increase its usable bass response).

https://www.psaudio.com/article/horns-part-3-2/

One can do it with a "non horn loaded" loudspeaker, too (e.g., Klipsch's own "Cornwall", which used horns for MR and HF, but had a conventional direct-radiator woofer (in a ported enclosure) for bass.

 

[0Hz]

Just wanted to report back and say that I have found a workable compromise in lowering the crossover , but keeping the volume relatively around the halfway point on my dial. Pop music seems pretty acceptable, some of my favorite rock/hard rock stuff does feel kind of "thin" and my chiptunes and EDM sound decent, though a little lacking in some frequencies, and I've seen some weird artifacts in a couple of favorite songs where the problem is coming more from the speakers. I haven't tested hiphop yet, but I suspect most of it will sound alright.

But I guess that is life as a nitpick.. Might get around to that corner loading placement eventually, but I think in the end, with the kind of money I have to spend and the listening space I have, the next investment will just be a miniDSP, so I can try and do some corrective gains and reductions around certain frequencies on both the sub and the main speakers.

Thanks for advice all. It's definitely not as boomy as before at least. Integration feels a lot more natural than it did before.

 

[Harvestor]

https://www.google.com/shopping/pro...qRoDUzE86Efrco1jpcg6yiVgLtgomuRoCmkMQAvD_BwE#

Gently spread 2 inch wide uniform amount of this on inside of cone to dampen unwanted thumping....use surgical gloves and index finger

 

[Imprecise]

https://www.google.com/shopping/pro...qRoDUzE86Efrco1jpcg6yiVgLtgomuRoCmkMQAvD_BwE#

Gently spread 2 inch wide uniform amount of this on inside of cone to dampen unwanted thumping....use surgical gloves and index finger

That would only help with hair bands.

 

[bowtie427ss]

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

I think the foam needs to go in the corners of the room. It's a small, acoustically hard room. There are as many issues with the room as the sub.

 

[jobrewer1983]

I think the foam needs to go in the corners of the room. It's a small, acoustically hard room. There are as many issues with the room as the sub.

Agreed 100%, as stated above placement is key with this style of sub... Can only work with the info given

 

[Gazdatronik]

Wow nice can of worms I opened huh....

I agree with a lot of the points here, there are many angles for me to investigate. I think part of the problem is I likely want/need speakers with better mid-range drivers / design to help with some of the "low but not that low" frequencies that I like to hear.
I suspected some of it is room placement that I need to try and experiment with, and I suspect that also some of it may be finding the right crossover setting. I did turn the crossover down. I think it maybe helped a little, but not quite in the way I would have expected. I still have thumpy kicks, but then I feel like I maybe lose a little of those slightly higher frequencies I actually want to hear.

It's very unnerving knowing you can sit in a live performance with perfectly balanced bass that you can feel in the air just as much as you hear it, but you can't even come close to that at home (gotta invest serious $$ for that). Granted I'm not looking for something that reverberates the carbonation out of my soda. Just something balanced, where the kicks don't feel overbearing.

I suspect room placement, and ultimately, some EQ via a DSP of some sort will get me what I am looking for, on my budget. I actually have what I need to route my analog audio through my PC and run DSP on it, so I can always experiment with that, and also with existing digital audio files.

Right now where I am at is, the crossover is set somewhere a smidge off the 80hz line (poor labeling, its 80, 100, 160 in 3 chunks....) and the volume more or less where I had it before. Maybe a touch increased. The thuds are somewhat subdued now, but to really hear some of the reinforced frequencies I was looking for I more or less have to play musical chairs around the room, or stand close to/over the subwoofer.

I haven't tested it with any of my YM2612 based vinyl yet, which really can have some thumping bass and drums, but PC audio is alright, although still a little "thin" as its always been.

I'm trying to avoid abusing the tone control on my SX-636 to crank the bass up (which helps with the speakers themselves) although I wonder again if maybe doing that, and then keeping the volume of the sub much lower might actually work out.

I'll try it sometime when people aren't around to get annoyed I guess.

I appreciate all your responses. But that math looking chart stuff is over my head

What are your mains? If you said before, i missed it

 

[frommerstop]

I know it’s a little thing, but since folks always jump on anyone here using the spelling “base” rather than “bass”, I thought I should point out the correct term here is damp, NOT dampen.

You wish to damp the bass... to dampen the bass would no doubt cause damage, or at least leave ugly rings!

 

[0Hz]

I know it’s a little thing, but since folks always jump on anyone here using the spelling “base” rather than “bass”, I thought I should point out the correct term here is damp, NOT dampen.

You wish to damp the bass... to dampen the bass would no doubt cause damage, or at least leave ugly rings!

The primary definition for both words involves moisture of some degree, so let's just settle for we're both right and both wrong.

What I should have said was that I wish to damp / dampen the output.

 

[0Hz]

Agreed 100%, as stated above placement is key with this style of sub... Can only work with the info given

I have thought about this. I don't know about foam, but some carpet/padding of some sort on the corners was a thought I had.. "that's dumb" I told myself....lol

What are your mains? If you said before, i missed it

I am using an unfortunately, slightly damaged set of Pioneer S-500X speakers. The speaker I have designated for the left channel suffered shipping damage to the particle board backing so it is no longer sealed back there. I am considering taping it up until I have the balls to attempt a repair/replace job. I don't think they are causing any issues with the issue in this thread, although they do have issues of their own that I am confident I can work out with some EQ.