DIY Subwoofer Risers

[jomari]

you can always try these...


2 of em, a peice of plywood and viola, the best riser on the fly!

[crazyBLUE]

Originally Posted by jomari

you can always try these...


2 of em, a peice of plywood and viola, the best riser on the fly!

May as well hang the sub from the ceilling !!

[JJ]

Originally Posted by jomari

ARCHITECTURE!?!

Thats not right.

delegate man. you should know this by now.

Ah, I'm an A student anyway. I'd rather be tearing speakers open or reading about history than designing another urban town plan. Talk about messy priorities. Architecture is only my 3rd love after History and Speakers.

Originally Posted by liquidice

perhaps if you spent less time changing your avatar every 15 minutes, you'd have time to cut a simple piece of wood and attach legs and carpet to it!!!

@ Avatar remark. And YES I know about your couches. Wouldn't have had a debate over it if a certain someone hadn't been drinking that evening.

Originally Posted by liquidice

Anyways, like I said, I think you can build something totally better than what Auralex can sell you, that is unless you want to settle for 'below average'? Pre-loaded question.

Heck, that black velour finish had me almost click the Buy button on the Sweetwater Acoustics website that sells these damnable things. Egh, I'll muse on it tomorrow - I was actually planning on buying an Elite SACD player, now I have to muse on making/getting a riser or two. *&%@#$

[liquidice]

make the riser a priority...trust us....TRUST US!!!

[crazyBLUE]

Originally Posted by liquidice

make the riser a priority...trust us....TRUST US!!!

I Second that !!

[liquidice]

Originally Posted by Big Daddy

Yes, everytime I change anything that affects the subs, I have to go back and redo the equalization with the Velodyne.

so what I'm getting at, is how drastic was the difference in your readings from before you built the risers, to after you built them. Did you compare?

[Big Daddy]

Originally Posted by liquidice

so what I'm getting at, is how drastic was the difference in your readings from before you built the risers, to after you built them. Did you compare?

The curve was completely different. When I looked at after all the changes, the curve was off the chart and looked completely weired. Different frequencies were emphasized. I had to lower the level of all the subwoofers and de-emphasize those exaggerated frequencies. After some time, I decided to reset everything to default (flat) and start all over again. It took me a while, but it was worthed. The bass sound in my HT room is as good as I could make it. Thank god we have no close neighbors.

[erict]

Originally Posted by Big Daddy

Sometimes the legs or spikes with down-firing subs that come from the manufacturer are too short. If you can replace them with something a few inches longer, it may help.

I should actually rephrase that. I will keep the spikes on the sub but when I build the riser I will not use four legs to elevate it. I will make a box frame (1x4) instead then place a carpeted board on top, then place the sub on it with the included spike feet. How does that sound?

[Fors*]

I have another question, I'm trying to figure out if I should attach 10" legs to my decoupler (thus making it a riser) using my subs small 2" legs (thus I would only have 2" of space directly under the sub) or if I should just attach 10" legs to the sub with a decoupler underneath, thus allowing for 10" of space directly under the sub? In this scenario, I just don't know if more space directly under the sub provides overall better bass or not.....

So, I am just looking for opinions as to what you guys would do if you were forced to pick one in this situation.......thanks guys!

[aramis109]

Originally Posted by forsberg21

I have another question, I'm trying to figure out if I should attach 10" legs to my decoupler (thus making it a riser) using my subs small 2" legs (thus I would only have 2" of space directly under the sub) or if I should just attach 10" legs to the sub with a decoupler underneath, thus allowing for 10" of space directly under the sub? In this scenario, I just don't know if more space directly under the sub provides overall better bass or not.....

So, I am just looking for opinions as to what you guys would do if you were forced to pick one in this situation.......thanks guys!

See, I guess I'm not understanding the point of everyone sticking legs on everything. The main purpose of the Auralex is to decouple the sub from the floor. After doing that, what purpose is sticking some big legs on it going to do besides (IMHO) look ... homemade, to put it nicely? If all subs (as some folks seem to be implying blindly) can benefit simply from being up higher, then why aren't manufacturers of the high end stuff doing that? I recognize there are some extreme decoupling pieces on the market that DO raise the sub up, but I'm afraid I'm not seeing the science behind the thought. I can easily see and hear the reasons for decoupling- last night I could hear the fan upstairs rumbling on the floor until I put something under it. Voila- no sound. But if I put it on a ladder which reverberated, and then it rumbled on the floor... what's the difference?!

[aramis109]

Let it not be said that I cannot admit when I'm wrong. I don't totally understand the science here. but in talking with BD he directed me to this post. I'm going to quote it below.

My bloody Auralex got delayed in shipping until tomorrow, so I'll not be able to provide feedback on it till tomorrow evening. Too bad too- wife and daughter left and I'm jamming Doomsday. Great LFE flick.

Anyway, here's BD's post:

Originally Posted by Big Daddy

The sound waves interact with the room boundaries (walls, floor, and ceiling) and create standing waves or room modes. The standing waves are different between floor and ceiling, side walls, and end walls, unless any of these dimensions are the same (the worst kind of room is a perfect cube). There are three basic types of modes: axial, tangential, and oblique. Examples of these modes are shown in the following diagrams:

Source: Marktaw.com

Axial Modes are the strongest and the most important, and the easiest to compute. Tangential Modes are about half as loud, and Oblique Modes are about a quarter as loud. They tend to be the least important, but if an oblique room mode occurs near another mode, that frequency may still be a problem.

If you look at the diagrams, you will notice that there are basically two types of axial modes: horizontal and vertical. Almost every person who owns a subwoofer discovers that room placement plays an important role. In reality, by moving the subwoofer around, you are dealing with the horizontal axial mode. Unfortunately, subwoofers do not understand horizontal or vertical. These classifications are in our heads. As far as subwoofers are concerned, waves are waves. We need to deal with vertical axial modes exactly the same way we dealt with horizontal axial mode, but how can we do that as Sir Isaac Newton and gravity work against us. There are two options: put the subwoofer on a riser or hang it from the ceiling and get shot by the wife in the process.

For additional information, read a A Guide to Subwoofers (Part II) : Standing Waves & Room Modes.

[liquidice]

and this is the beautiful thing about my riser, which I'll always call my "GRAMPA", but have put my own twist into. The riser is raised with 6" legs, and not just covered with carpet, but rubberized carpet. So there is your first example of decoupler vs riser. Then I took one of my precious Auralux bass traps, and butchered the living crap out of it to glue it to the bottom of the riser, and setting it just so the bass trap slightly pushes into the ground underneath. With this combination, I believe to have found the perfect subwoofer enhancement for my application. Of course this may not be ideal for everyone, but it's personalized for my taste, and it's results are impressive.

[Fors*]

I'm going to look into getting the table legs that BD talks about and perhaps rise my decoupler, thus making it a riser. A simple and cheap tweak that I know I can do. I only wish I had the disregard for some coin to forfeit for a bass trap like ice from Auralux. Man, that stuff is pricey....damn!

[jomari]

Originally Posted by liquidice

and this is the beautiful thing about my riser, which I'll always call my "GRAMPA", but have put my own twist into. The riser is raised with 6" legs, and not just covered with carpet, but rubberized carpet. So there is your first example of decoupler vs riser.

show off! hehehe. seriously, great job on the riser you created.

aramis, ive had a little discussion with JJ actually yesterday about this, and what the main difference from a riser and a decoupler is. heres the bulk of what ive mentioned...

The Grammas from auralex were intended as decouplers and not as risers, with its primary goal is to isolate the amp/subwoofer from the ground further reducing the coupling with the floor and the room.

isolation comes in two forms : decoupling or coupling, you either want the device (which can be a speaker, an amp, a turntable) to either couple (interact) with the room or not.

Decoupling prevents it, or minimizes it at least.

Coupling increases its participation in the room, which is done mostly with speakers, and allows you to have more interaction with it. There are a number of reasons why most people prefer to decouple the speakers, including 'false' gain increases, as well as coloration.

You want to listen to the music, and not the room. - the reasoning behind acoustic treatments.

in regards to risers, with risers you are addressing the room mode. two different things.

decoupling speakers removes the interaction of the speakers, while risers ADDRESS room interaction.

passive acoustics versus active acoustic treatments.

so why dont subwoofer companies not provide such risers? why do we have center speakers that have lobing issues? Why dont speaker companies stuff everything with polyfill? why arent power filters included in each AVR and/or pre/pro?

There can be a number of reasons, but aside from marketing, the one that comes up would be because subwoofers were built to be easier to place.

We've removed the subwoofer, the lower frequencies of most speakers and placed them in a big huge box. aside from aesthetics, i dont see any reason for them to add on huge risers on them to improve performance. Ive also considered that each room has different vertical needs to be addressed, thus no common denominator for a risers height.

As mentioned, we just try small things here and there to help out with our room, but dont necessarily believe them to be the most imperative part of a home theater build. if you're room is acoustically tight, and have the proper placement of each component in the room, then theres no need to address them.

[Big Daddy]

Originally Posted by forsberg21

I'm going to look into getting the table legs that BD talks about and perhaps rise my decoupler, thus making it a riser. A simple and cheap tweak that I know I can do. I only wish I had the disregard for some coin to forfeit for a bass trap like ice from Auralex. Man, that stuff is pricey....damn!

The legs and plates are so easy to install. Since the legs are screwed in, you can remove them easily. Both Lowes and Home Depot have them. They have different styles. They go from a couple of inches to a couple of feet. Before, you make your final decision, visit both stores and see which ones you like the most.

If you put carpet around them, it will look the best. Alternatively, you can paint them. I prefer carpeting.

[JJ]

Liquid, I was actually about to test out putting my two bass traps together so they form a prism, and put my Dynamo on that just for testing. Haven't tried it yet, though.

Question for you, Pops. Are these applications necessary for larger subwoofers, such as the SVS cylinders that are already 4'-0" tall and Axioms EP600 sub? Or do these take this vertical spacing into account?

[Fors*]

Originally Posted by Big Daddy

The legs and plates are so easy to install. Since the legs are screwed in, you can remove them easily. Both Lowes and Home Depot have them. They have different styles. They go from a couple of inches to a couple of feet. Before, you make your final decision, visit both stores and see which ones you like the most.

If you put carpet around them, it will look the best. Alternatively, you can paint them. I prefer carpeting.

Yep, this does it.....I'm going to Lowes as soon possible. My only problem is that Lowes is right across the street from my favorite watering hole and when I tell her "I'm going to Lowes" she has caught on and knows it is my code to have a few , but I never come home like this...

[erict]

Originally Posted by forsberg21

Yep, this does it.....I'm going to Lowes as soon possible. My only problem is that Lowes is right across the street from my favorite watering hole and when I tell her "I'm going to Lowes" she has caught on and thinks that means I am on my way to have a few , but I never come home like this...

With playoffs starting you're going to need a few GO WINGS

[jomari]

Originally Posted by JJxiv1215

Liquid, I was actually about to test out putting my two bass traps together so they form a prism, and put my Dynamo on that just for testing. Haven't tried it yet, though.

the way i see it, just lifting the subwoofer up from its current position would affect it at one point or another, because you've changed its vertical position, thus also reducing room interaction. heck put it on a box of eggs would already put your sub in a better spot.

but thats the thing, we have to consider decoupling it to avoid any unwanted noise, like rattling, or reflections et al.

you can build a riser, and not even bother decoupling the speaker. but hey, you might as well consider it while on the project.

[Big Daddy]

Originally Posted by forsberg21

Yep, this does it.....I'm going to Lowes as soon possible. My only problem is that Lowes is right across the street from my favorite watering hole and when I tell her "I'm going to Lowes" she has caught on and knows it is my code to have a few , but I never come home like this...

This is the difference between men and women. This picture shows the recation of a man or a woman when you ask them:

"Let's go have a drink".

Beer.jpg