DIY Subwoofer Risers

[Big Daddy]

Originally Posted by lolwaut

ok great...

the crushed velvet fabric i have isnt thick... it is actually so thin that you can stretch it and see through it in some places. so, not ideal for dampening which is what i was concerned about to begin with. although, i think some thin foam underneath it (per your suggestion) will make it more than adequate.

now another question, i went and bought some wood about an hour ago. the birch plywood was way too expensive.... 50 bucks for a sheet. i might as well just buy a pre-assembled riser at that price. the MDF board was more reasonable, but still 25 bucks a sheet and i didnt really want to spend that much. instead, i bought some 3/4 pine ply wood for 11 bucks. is there any reason that pine isnt as good as the birch or MDF you suggested?

The pine should work without a problem. Home Depot and Lowes have a section where they sell smaller pieces of MDF and birch panels (48" length) for less than $10. It is in the table top section. That is where I bought mine. They also sell short table legs with installation hardware. Look at Post #2 for all the detail and pictures.

[lolwaut]

Originally Posted by Big Daddy

The pine should work without a problem. Home Depot and Lowes have a section where they sell smaller pieces of MDF and birch panels (48" length) for less than $10. It is in the table top section. That is where I bought mine. They also sell short table legs with installation hardware. Look at Post #2 for all the detail and pictures.

doh! i wish i would have known that... not only would i have got better quality wood for less money, but i wouldnt have all this extra damn wood. oh well... im just glad to hear that the pine will work.

thank you all for your help! ill post pictures post-construction.

[HAMP]

I think I may try this. Do you think it would help if I put little rubber tabs on the bottom or just leave it like it is on top of the carpet?(for my sub-12', not the picture's below) I don't know how I would do that one for the sub below, since no legs are there.

Hey BD,
I don't know if you remember us talking about me adding a sealed sub to the two ported subs. I actually had the thing built, but never did try it out like I planned.

When I added the Denon to the bedroom and removed the HTiB, I didn't have a sub. The HTiB sub was getting it's power from the reciever and I ended up using this(picture below) sub in the bedroom.




The amp plate is for a Klipsch sub-12, but I am using a Kicker 10" woofer
I didn't pay that price for the woofer, I only paid $65 for it.

[aramis109]

Originally Posted by HAMP

I think I may try this. Do you think it would help if I put little rubber tabs on the bottom or just leave it like it is on top of the carpet?(for my sub-12', not the picture's below) I don't know how I would do that one for the sub below, since no legs are there.

Hey BD,
I don't know if you remember us talking about me adding a sealed sub to the two ported subs. I actually had the thing built, but never did try it out like I planned.

When I added the Denon to the bedroom and removed the HTiB, I didn't have a sub. The HTiB sub was getting it's power from the reciever and I ended up using this(picture below) sub in the bedroom.



The amp plate is for a Klipsch sub-12, but I am using a Kicker 10" woofer
I didn't pay that price for the woofer, I only paid $65 for it.

Wow, looks really nice! So, how's it sound? I notice it's sealed- run any test tones on it to test how low it'll go? You did really good work on it!

You guys are making me jealous- I don't have the tools for some of these projects but the work coming out of this thread is really nice.

[Big Daddy]

Originally Posted by HAMP

I think I may try this. Do you think it would help if I put little rubber tabs on the bottom or just leave it like it is on top of the carpet?(for my sub-12', not the picture's below) I don't know how I would do that one for the sub below, since no legs are there.

It doesn't hurt to add rubber in the bottom. On carpet, it may not help a lot, but on wood or tiles, it is definitely better. For the other sub, you should add legs or spikes. At Home Depot and Lowes, they sell low cost 2" to 12" table legs with installation hardware. It is very easy to add them to the sub with short screws.

Hey BD,
I don't know if you remember us talking about me adding a sealed sub to the two ported subs. I actually had the thing built, but never did try it out like I planned.

I didn't pay that price for the woofer, I only paid $65 for it.

That subwoofer looks good and professional.

[liquidice]

yeah, I'd be curious too about how the Kicker sub hits. I don't know the limitations or benefits of a sealed box first hand. Do you have a way to run test tones?

[HAMP]

Originally Posted by aramis109

Wow, looks really nice! So, how's it sound? I notice it's sealed- run any test tones on it to test how low it'll go? You did really good work on it!

Thank you! It sounds really good and the best way I can describe it, even though it's in my bedroom and not much space you truly cannot tell where it’s located when the bass hits. The bass hits, the sound in the room sounds like the surrounds are actually creating the bass.

Unlike my other subs, if you close your eyes and listen you feel it and the room is filled with bass, but you can tell where they are. This new one is not like that and I'm not sure if it's because it's a sealed box compared to two ported subs. I do have another amp plate that I am going to build another, but that will be for my house to have four subs(2 sealed, 2 ported) in my theater room.

Originally Posted by Big Daddy

It doesn't hurt to add rubber in the bottom. On carpet, it may not help a lot, but on wood or tiles, it is definitely better. For the other sub, you should add legs or spikes. At Home Depot and Lowes, they sell low cost 2" to 12" table legs with installation hardware. It is very easy to add them to the sub with short screws.

I will be looking into adding the rubber bottom's for the two ported subs and also some legs or spikes for the sealed. I will keep the carpet under them it stops the subs from dancing away.

Originally Posted by liquidice

yeah, I'd be curious too about how the Kicker sub hits. I don't know the limitations or benefits of a sealed box first hand. Do you have a way to run test tones?

No I don't have away for the test tones, my PS3(for internet access for test tone pages) is not in the bedroom.

I can only go by what is provided in the spec's for this sub(as low as 25Hz).

[liquidice]

I see ED is having a B stock and open box sale right now, and there are various subs, cabinets, and plate amps listed for sale. Might have to do some frankenstein work myself. Prices aren't listed, but I'm sure they are pushing this stuff out at a good price.

[erict]

Originally Posted by liquidice

I see ED is having a B stock and open box sale right now, and there are various subs, cabinets, and plate amps listed for sale. Might have to do some frankenstein work myself. Prices aren't listed, but I'm sure they are pushing this stuff out at a good price.

Where do you see this????

[aramis109]

Originally Posted by HAMP

Thank you! It sounds really good and the best way I can describe it, even though it's in my bedroom and not much space you truly cannot tell where it’s located when the bass hits. The bass hits, the sound in the room sounds like the surrounds are actually creating the bass.

Unlike my other subs, if you close your eyes and listen you feel it and the room is filled with bass, but you can tell where they are. This new one is not like that and I'm not sure if it's because it's a sealed box compared to two ported subs. I do have another amp plate that I am going to build another, but that will be for my house to have four subs(2 sealed, 2 ported) in my theater room.



I will be looking into adding the rubber bottom's for the two ported subs and also some legs or spikes for the sealed. I will keep the carpet under them it stops the subs from dancing away.


No I don't have away for the test tones, my PS3(for internet access for test tone pages) is not in the bedroom.

I can only go by what is provided in the spec's for this sub(as low as 25Hz).

Cool- assuming the spec is correct 25hz is really nice for a sub that size. So, how'd you do the carpeting on it so nicely? Did you buy a pre-made box or make your own?

eD B-stock sale: http://forum.edesignaudio.com/showth...and-71361.html

[liquidice]

Originally Posted by erict

Where do you see this????

why, right here my good man. You just have to signup for the ED forum, and then PM Alex for prices, and special requests not listed. Kind of sounds like their doing a little spring cleaning. Might even take 'best offer' requests! Worth a shot.

[HAMP]

I went to Home Depot to get the little wooden blocks and I wanted to get some type of rubber bottoms to help, but then I came across these


I kinda want to make them a tad bit taller, I'm not sure if I will leave them as they are or glue a wooden block under them to make them a inch higher.

I forgot to mention, they came in a pack of four for $2.28

[awongshing]

I just made my own riser for my subwoofer. Does anybody use a riser and if so did it make a significant improvement in the performance of your subwoofer?
Thanks,

[crazyBLUE]

Originally Posted by awongshing

I just made my own riser for my subwoofer. Does anybody use a riser and if so did it make a significant improvement in the performance of your subwoofer?
Thanks,

I built A riser for my sub ! Yes it improved the sound some . I do think that filling the sub with poly-fill as well as the riser has helped the most on the sub being boomy & muddy sounding !

[Fors*]

Originally Posted by awongshing

I just made my own riser for my subwoofer. Does anybody use a riser and if so did it make a significant improvement in the performance of your subwoofer?
Thanks,

I made my own sub riser as well thanks to Big Daddy's help. There are pics of mine in my gallery. Yes it will help, it will make the sound louder, even clearer. You also want to dampen the riser as much as possible to help with any port noise, so did you use any carpet and did you attach anything under your riser for further dampening? I noticed improvement in the "tightness" from my sub after building my riser. Also, crazy is right about the use of polyfill as well, it helps to make the sub seem "bigger."

If it helps, I attached a nice post from our own Big Daddy about the benefits of a sub riser, Post #223....

Front-firing and down-firing is something in our heads. Subwoofers and waves do not care. Waves are waves and go in every direction, particularly the long wavelengths of low frequency sound.

The biggest effect when you raise a subwoofer is that it may become a lot louder. You don't have to believe me or CrazyBlue. There is scientific reason behind this.

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.

Low frequency wavelengths are much longer (e.g., 56.5ft at 20Hz, 22.6ft at 50Hz, and 11.3ft at 100Hz) than higher frequency wavelengths (e.g., 3.8ft at 300Hz, 1.1ft at 1,000Hz, and 1 inch at 13,000Hz). This is important, especially below 150hz or so. Above 150hz, the waves are small enough that they are not affected by the room size as much. They bounce around every which way. Standing waves only become a significant problem at lower frequencies (below 100 Hz) because we normally set the crossover frequency around 85Hz. Long wavelength bass frequencies travel back and forth bouncing off the walls.

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. It is best to calculate all room modes to see where any overlap may be.

The three types of AXIAL modes are LENGTH, WIDTH, and HEIGHT. Knowing the speed of sound and the wavelengths of different frequencies, we can easily calculate these three types of axial modes.

When you move a subwoofer around a room, you are basically trying to deal with horizontal axial resonance modes (length and width). Almost everybody discovers this and tries to deal with it. Unfortunately, the vast majority of people are not aware that subwoofers and waves do not understand horizontal or vertical. By raising a subwoofer, you are actually dealing with the vertical (height) resonance mode.

To fully understand this, be patient and read A Guide to Subwoofers (Part II): Standing Waves & Room Modes.

or you can read Big Daddy's sticky if you haven't already..

https://forum.blu-ray.com/showthread.php?t=74527

Finally,where's the pics? We needs pics or it never happened.....
__________________

[Aerodude73]

Def. some type or riser will Help as well as filling it loosely with Polyfill (full, but not over-stuffing - loosely so it fills the entire enclosure). I have a SubDude (see my Sig. below if you're not sure of that item), plus, just recently, I put both the Sub & SubDude on a 20x20x17 (L/W/H) little $23 end table I got from Walmart, making it about 21" off the ground. Totally makes it kick butt being that high. I'll have pics of that soon, but you get the idea.

[erict]

Originally Posted by awongshing

I just made my own riser for my subwoofer. Does anybody use a riser and if so did it make a significant improvement in the performance of your subwoofer?
Thanks,

Pics, we need pics to make sure you really built one

[awongshing]

Originally Posted by erict

Pics, we need pics to make sure you really built one

I will post pics soon. I have to paint it. Right now it's just ugly

[Fors*]

Originally Posted by awongshing

I will post pics soon. I have to paint it. Right now it's just ugly

But effective.......yes?!

[erict]

Originally Posted by awongshing

I will post pics soon. I have to paint it. Right now it's just ugly

Well then just take before and after pics