Raising my sub

[Yeha-Noha]

Originally Posted by progers13

Thanks - I went to Home Depot this morning actually and found them in the flooring section.

I just visited your gallery. Yep, those are the ones. That might even work better than mine. I'm getting tempted to buy a pack of those and cut them to fit the exact size of my sub. I don't want the textured side to be bigger than the sub and thus be showing. I suppose you'll cut yours too after you finish experimenting. Does it matter which side is up, textured or smooth? If you try double thickness, please I'd like to know if that made a difference too.

[progers13]

Originally Posted by rwojtalewicz

Great! Those are interlocking to fit under a washer or dryer, right? If I remember correctly, I saw them at Home Depot too. I would cut them to size and double them up to give 1.5 inch thickness. Those should work terrific too since their purpose is to reduce vibrations from washers, dryers, etc. Good choice.

We had something similar to this at my previous place of employment. They're designed to provide cushioning for the feet. We had about 100' around the machinery, and it really helped to minimize fatigue from being on our feet all day. It's got a rubbery surface, but it's foam inside. I actually cut the one I bought in half and used each section for my 2 subs. I may double it up at some point, but all in all it seems to be making a positive difference as it is now. I've tried using rugs, carpet, towels, but this has better results. Good suggestion!

[progers13]

Originally Posted by rwojtalewicz

I just visited your gallery. Yep, those are the ones. That might even work better than mine. I'm getting tempted to buy a pack of those and cut them to fit the exact size of my sub. I don't want the textured side to be bigger than the sub and thus be showing. I suppose you'll cut yours too after you finish experimenting. Does it matter which side is up, textured or smooth? If you try double thickness, please I'd like to know if that made a difference too.

I haven't tried flipping it to the non-textured side. I'll have to do that and let you know.

[picture_shooter]

Originally Posted by solarrdadd

here are a couple of things i don't understand. folks are stuffing their speakers and subs and raising them up on stands and such off of the floor, ok. why aren't these things being done or recommended by the makers of these products if they work so well? mind you, i'm not saying they don't work well either. i'm saying why don't the engineers who designed these things have it done at their level for the products if all of these things so dramatically increase the quality of the sound and effectiveness of their products? aren't they missing out on money that they could be charging for these "improvements" ? mind you i've not stuffed or raised any speaker or sub so i'm putting it out there for those who have or are thinking of doing it.

have at it people!

Everything is about ear level.

So if most speakers / subs are raised @ ear level it does sound better.

I know for one, on my MFW15 and if you were to stand up and be back about 10' it sounds ok. Then when I bow-down to the ground / laydown 10' away from the sub, the bass level is so much more.

I have a buddy that has a POS 8" sony sub, that he now just rises it on a stool to make it ear level and he loves the way the sub sounds (musical of course).

It does make a difference and not sure why they just don't make subs that look like a tower . I am sure it would be friggen huge and of couse much more expensive to develope / manufacture. This is why DIY is something big now

[Yeha-Noha]

Originally Posted by picture_shooter

Everything is about ear level.

So if most speakers / subs are raised @ ear level it does sound better.

I know for one, on my MFW15 and if you were to stand up and be back about 10' it sounds ok. Then when I bow-down to the ground / laydown 10' away from the sub, the bass level is so much more.

I have a buddy that has a POS 8" sony sub, that he now just rises it on a stool to make it ear level and he loves the way the sub sounds (musical of course).

It does make a difference and not sure why they just don't make subs that look like a tower . I am sure it would be friggen huge and of couse much more expensive to develope / manufacture. This is why DIY is something big now

It's true that for tower speakers with tweeters and midrange drivers, you do want those at ear level to sound better. Bookshelf speakers need to be on stands to bring them to ear level as well. Of course we all know this.

To use subwoofers most effectively, most of us set the crossover frequency for tower speakers somewhere around 40 Hz to 80 Hz maybe a little higher if needed. However, it isn't necessary to place subwoofers on stands to be at ear level because bass is non directional at 80 Hz and below.

I am convinced that 1" - 2" foam pads, or Auralex SubDudes, are an effective way yet for obtaining tight bass response, eliminating boomy bass, and significantly reducing vibrations in my HT room and around the house. These isolate the subwoofer from the floor. So I just use 1" thick neoprene foam rubber pads under my subwoofers. I am very happy with the bass performance from my subs.

Of course there is no exception to the fact that proper subwoofer placement in the room, or using multiple subs in pairs or fours, is the best way to get top notch bass performance. So accordingly I have two subwoofers in my HT room.

Placing my subs on tall stands to bring them up to ear level would look ugly in my room's decor and an eyesore.

I am certainly fascinated that others can do this. What's more fascinating is the testimonials about getting better bass performance. That's intriguing and may well be true or, OTOH, maybe it's just the placebo effect. I don't know. But, I won't be convinced unless there's a scientific study providing data that unmistakably supports those claims. Even if there is such a study, and bass performance is improved by such a practice, I for one won't be putting my subs on stands bringing them up to ear level. My wife won't stand for it.

[Fors*]

Plus with the way subs interact with a room's boundaries, there is no true test that is applicable to everyone's HT where the matter is black and white. It's more of a matter of trial and error, with location being the biggest variable. Once you raise the subwoofer to deal with the axial modes, you are introducing additional variables that will once again, have different results in different rooms. I do think there is improvement in bass response when you do these little tweaks. Some of it may be so marginal or small that it is only the placebo effect, but there are other tweaks that I truly believe do make a signfiicant enough improvement that it can be easily heard by the human ear too.

[Big Daddy]

Originally Posted by rwojtalewicz

To use subwoofers most effectively, most of us set the crossover frequency for tower speakers somewhere around 40 Hz to 80 Hz maybe a little higher if needed. However, it isn't necessary to place subwoofers on stands to be at ear level because bass is non directional at 80 Hz and below.

Of course there is no exception to the fact that proper subwoofer placement in the room, or using multiple subs in pairs or fours, is the best way to get top notch bass performance. So accordingly I have two subwoofers in my HT room.

Placing my subs on tall stands to bring them up to ear level would look ugly in my room's decor and an eyesore.

I am certainly fascinated that others can do this. What's more fascinating is the testimonials about getting better bass performance. That's intriguing and may well be true or, OTOH, maybe it's just the placebo effect. I don't know. But, I won't be convinced unless there's a scientific study providing data that unmistakably supports those claims. Even if there is such a study, and bass performance is improved by such a practice, I for one won't be putting my subs on stands bringing them up to ear level. My wife won't stand for it.

Nobody is talking about bringing subwoofers to ear level. If anyone makes that claim, that person is mistaken.

If you believe in the hypothesis that positioning in the room has an important effect on the performance of a subwoofer, you are indirectly admitting that the horizontal axial mode is an important factor. What makes you think a subwoofer understands horizontal or vertical? Bass waves have long wavelengths and interact with room boundaries (walls, celing and floor) and create standing waves and room modes. They don't care about ear level or location. We, on the other hand, want to get the maximum output from our subwoofers. As a result, we move the subwoofer around to deal with these nasty room modes. Another solution as you admit is to get 2 or 4 subwoofers.

All the above tweaks only deal with horizontal axial modes. To deal with vertical axial mode (floor and ceiling), we need to move the subwoofer vertically. Unfortunately, gravity works against us. We are left with two options: raise it from the floor or hang from the ceiling. This has been scientifically proven at the National Research Council of Canada and at Harmon International.

You can believe what you want to believe and say that it is placebo. I tested the riser effect with an SPL meter in my HT room with 4 subwoofers. After raising them, I got a 10dB increase in the level of bass output. To the best of my knowledge, the Radio Shack SPL meter does not have placebo.

[crazyBLUE]

You always end your posts just right Big Daddy !

[Yeha-Noha]

Originally Posted by Big Daddy

Nobody is talking about bringing subwoofers to ear level. If anyone makes that claim, that person is mistaken.

If you believe in the hypothesis that positioning in the room has an important effect on the performance of a subwoofer, you are indirectly admitting that the horizontal axial mode is an important factor. What makes you think a subwoofer understands horizontal or vertical? Bass waves have long wavelengths and interact with room boundaries (walls, celing and floor) and create standing waves and room modes. They don't care about ear level or location. We, on the other hand, want to get the maximum output from our subwoofers. As a result, we move the subwoofer around to deal with these nasty room modes. Another solution as you admit is to get 2 or 4 subwoofers.

All the above tweaks only deal with horizontal axial modes. To deal with vertical axial mode (floor and ceiling), we need to move the subwoofer vertically. Unfortunately, gravity works against us. We are left with two options: raise it from the floor or hang from the ceiling. This has been scientifically proven at the National Research Council of Canada and at Harmon International.

You can believe what you want to believe and say that it is placebo. I tested the riser effect with an SPL meter in my HT room with 4 subwoofers. After raising them, I got a 10dB increase in the level of bass output. To the best of my knowledge, the Radio Shack SPL meter does not have placebo.

Ah, BD, you didn't read my post. I said, I don't know if it's real or due to placebo effect. You're too trigger happy with your flame thrower. Back off will you please?

Now, that's taken care of, we can get down to business because I want to know, even though I might not be able to raise my subs up that high. It's good to keep up with the science though. So, thank you for pointing me in the direction where I could find the scientific study that I was seeking, right here.

I haven't read it yet because I'm still at work. I will get on it later today.

[Big Daddy]

Originally Posted by rwojtalewicz

Ah, BD, you didn't read my post. I said, I don't know if it's real or due to placebo effect. You're too trigger happy with your flame thrower. Back off will you please?

Originally Posted by rwojtalewicz

I am certainly fascinated that others can do this. What's more fascinating is the testimonials about getting better bass performance. That's intriguing and may well be true or, OTOH, maybe it's just the placebo effect. I don't know. But, I won't be convinced unless there's a scientific study providing data that unmistakably supports those claims. Even if there is such a study, and bass performance is improved by such a practice, I for one won't be putting my subs on stands bringing them up to ear level.

You made this post after I provided scientific proof in my earlier post in this thread. I am not the one who is trigger happy and needs to back off. I responded directly to your post. The scientific theory behind risers was discussed in Posts #2 and #3 of DIY Risers thread and repeated in post #13 of this thread, but you refuse to read them or acknowledge them. You also do that with polyfill, despite the overwhelming evidence for its benefits.

Originally Posted by rwojtalewicz

Now, that's taken care of, we can get down to business because I want to know, even though I might not be able to raise my subs up that high. It's good to keep up with the science though. So, thank you for pointing me in the direction where I could find the scientific study that I was seeking, right here.

I haven't read it yet because I'm still at work. I will get on it later today.

You did not need to search for scientific proof. All you had to do was check A Guide to Subwoofers (Part II): Standing Waves & Room Modes thread. All the sources and scientific studies have been listed there at the end of Post #2 for over a year. The link that you found is Part 3 of a series of articles by Dr. Floyd Toole and has been listed as a reference there. Most of the research by Dr. Toole was done at the National Research Council of Canada before he became a Vice President at Harmon International. If you had read or glanced over that thread, you would have found all the information you were looking for.

[Yeha-Noha]

Originally Posted by Big Daddy

You made this post after I provided scientific proof in my earlier post in this thread. I am not the one who is trigger happy and needs to back off. I responded directly to your post. The scientific theory behind risers was discussed in Posts #2 and #3 of DIY Risers thread and repeated in post #13 of this thread, but you refuse to read them or acknowledge them. You also do that with polyfill, despite the overwhelming evidence for its benefits.

Big Daddy, saying that I refuse to read this or that, especially something that is of interest to me is a bad assumption on your part and totally untrue. I have read many of the posts here. Often I find myself reading only the most recent ones especially if that's all I have time for. I can't justify that of course, but it does happen. Then you made another bold statement stating that I refuse to acknowledge them. How is that possible when you predicated your assumption on my refusing to read them? If you didn't naively contradict yourself, then you aren't making any sense because what you have just stated is that I refuse to acknowledge what I refuse to read or putting it another way, what I didn't read.

I never even once said that using sub risers isn't based on valid science. You falsely assumed that I did and likewise assumed that I won't acknowledge it. I can't place my subs up that high because my wife will object and I have to agree with her that sub risers in my HT room would look objectionably out of place and ugly.

And here I thought our little discussion on polyfill had concluded. I acknowledged that polyfill has the purpose of making a closed box seem larger to the driver than the box's physical size which will lower the Qt and extend the bass response. Polyfill can be used to fine tune a vented box. If polyfill is used to extend the bass response it does so at the expense of efficiency. Citing the polyfill discussion as an example of what you falsely claim that I refuse to read or acknowledge what I have read, backfires on you, sir. Didn't you read my posts?

BD, you of all people should know by now, that I harbor skepticism until I am convinced that some DIY tweak, fix, or improvement is worth it especially in my HT room or in my setup even if there is valid scientific evidence showing that possiblity. I will weigh the pros vs the cons whether to make such an improvement as it pertains to my system. There is going to be a continuum of benefits for people trying these fixes ranging from none to earth shaking. Even some of the posts I read acknowledged that. You do us a good service BD, making this stuff available.

However, because I don't do the things you suggest, doesn't mean that I don't acknowledge them or shrug my shoulders saying there is no scientific basis to do those tweaks. You got to give people some latitude in their choices and respect their choices whether you agree with them or not. But don't go on and on hounding me like you did here making false statements that I won't acknowledge the science. That is totally untrue. You have to respect the fact that I have my reasons for not doing the tweaks that you or anyone else may suggest to the forum. I know I have been skeptical but did openly acknowledge that I was. Yet, you keep on and on relentlessly trying to convince me that I am wrong. It's my choice for not filling my sub with polyfill. Although it might be the wrong one for you but it's the right way for me. I have my reasons for not doing it, but certainly not because refuse to acknowledge the science behind it. I am aware of that. But people have to make up their own mind and accept compromises when there is no other option available. We all have to deal with that. I think we all do. I have a right to make up my own mind for my own reasons pertaining to my system. You can do what you want to yours and so can anyone else. I think we all can agree on that.

Originally Posted by Big Daddy;2416881You did not need to search for scientific proof. All you had to do was check [URL="https://forum.blu-ray.com/showthread.php?t=48286"

A Guide to Subwoofers (Part II): Standing Waves & Room Modes[/URL] thread. All the sources and scientific studies have been listed there at the end of Post #2 for over a year. The link that you found is Part 3 of a series of articles by Dr. Floyd Toole and has been listed as a reference there. Most of the research by Dr. Toole was done at the National Research Council of Canada before he became a Vice President at Harmon International. If you had read or glanced over that thread, you would have found all the information you were looking for.

Yes, Toole's articles look very interesting. Like I said, I will give them a read.

[Big Daddy]

Originally Posted by rwojtalewicz

If you didn't naively contradict yourself, then you aren't making any sense because what you have just stated is that I refuse to acknowledge what I refuse to read or putting it another way, what I didn't read.

I disagree. My statement was an OR statement and is not contradictory. I said that you either do not read OR do not acknowledge my posts. The second part simply means that even if you read them, you do not acknowledge them.

Despite my Post #13, the DIY Risers, and A Guide to Subwoofers (Part II), you made the statement that you have not seen the scientific proof. The two threads have been posted for many months now. Post #13 was there for you to see. You should have consulted them before making such general statements and asked for clarification if there were any ambiguities.

However, because I don't do the things you suggest, doesn't mean that I don't acknowledge them or shrug my shoulders saying there is no scientific basis to do those tweaks. You got to give people some latitude in their choices and respect their choices whether you agree with them or not.

In your defense, you are making unfair and false statements. Not once have I forced or encouraged you to do any of the tweaks that I have suggested. Show me the post where I did not give you the latitude (as you put it) to have the freedom of choice. Acknowledging the science behind something and doing it are two different things.

I really do not wish for this conversation to continue. Let's make peace and blame it on misunderstanding

[Yeha-Noha]

Originally Posted by Big Daddy

I disagree. My statement was an OR statement and is not contradictory. I said that you either do not read OR do not acknowledge my posts. The second part simply means that even if you read them, you do not acknowledge them.

Despite my Post #13, the DIY Risers, and A Guide to Subwoofers (Part II), you made the statement that you have not seen the scientific proof. The two threads have been posted for many months now. Post #13 was there for you to see. You should have consulted them before making such general statements and asked for clarification if there were any ambiguities.


In your defense, you are making unfair and false statements. Not once have I forced or encouraged you to do any of the tweaks that I have suggested. Show me the post where I did not give you the latitude (as you put it) to have the freedom of choice. Acknowledging the science behind something and doing it are two different things.

I really do not wish for this conversation to continue. Let's make peace and blame it on misunderstanding

Agreed.

[Big Daddy]

Originally Posted by rwojtalewicz

Agreed.

You are a gentleman.

[jomari]

rwo did have some very interesting points, and as ive considered big daddy as a great source, skepticism can be seen to a certain point. im sure that some of bd's reference material do hold water, and can show the results aside from his own. have i created risers to a good foot or two? nope. but i do know that i dont need it in my current situation. i can address the axial modes myself thank you.

there are tweaks, diy stuff that can further improve certain aspects of both the speaker, and the room its in to a certain degree. truly there are some tho that are palpable (like the 3 coin trick), and those that have created a stir at times (resonance pads, bracers, etc), and sometimes do work as well. i think that risers fall in the latter in my opinion. by theory, it does address the horizontal axial mode of the room, and pretty much makes sense. but this is of course, dependent on a number of variables, room environment as big numero uno.

i think at this point, we can just agree to disagree.

can we talk about bass traps now?

[Yeha-Noha]

Originally Posted by Big Daddy

You are a gentleman.

BD, that makes two gentlemen.

[crazyBLUE]

Originally Posted by rwojtalewicz

Agreed.

Originally Posted by Big Daddy

You are a gentleman.

[alopez65]

my living room is carpeted and my sub is just sitting on the floor. it has just an 8" driver,but i was considering raising it. will i hear a difference with a small sub as this? if so, i am wanting to build a subtrap and like the ones others have built. what do i use for a tube? i assume just one is needed. what fill do i use? do i leave the tube solid and hollow or am i suppose to drill holes, or fill it? can i use polyfill? thanks in advance for any advice.

[jomari]

Originally Posted by alopez65

my living room is carpeted and my sub is just sitting on the floor. it has just an 8" driver,but i was considering raising it. will i hear a difference with a small sub as this? if so, i am wanting to build a subtrap and like the ones others have built. what do i use for a tube? i assume just one is needed. what fill do i use? do i leave the tube solid and hollow or am i suppose to drill holes, or fill it? can i use polyfill? thanks in advance for any advice.

First off,
Building a subwoofer riser may or may not benefit you in the long run. it really depends on the room environment, and how your subwoofer relates to it. Placement is more of a priority instead of just 'raising' your sub. Ideal placement can be found in Big daddys thread about subwoofer placement.

Second, building bass traps can be explained further by acoustic treatments guru, Ethan winer, found here.... building a better bass trap

Lastly, we almost suggest having a SPL meter as much as possible. The best investment to have when calibrating your home theater is found for as little as 50 bucks from radio shack.

[alopez65]

thaks for the reply jomari. i checked that link and i think it pertains to a larger room; mine is only about 12 x12. my sub is out of the corner and away from adjacent walls about 18 inches. i think there is a little "boominess", but my wife says it sounds fine to her. maybe i should try a riser? i have some scrap lumber and carpet around the garage so it wouldn't cost anything to make one. i have the setting on my receiver to 0db for the sub.