Raising Subs off floor 4" or so. - AVS Forum
Forum Jump: 
 
Thread Tools
post #1 of 8 Old 01-26-2012, 08:25 AM - Thread Starter
Advanced Member
 
ADDUpstate's Avatar
 
Join Date: Mar 2011
Location: Perinton NY
Posts: 649
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Hi all,

I have 2 sealed, front firing 15" subs.

In redesigning some of my dedicated HT, I have realized that I would like to raise the subs up by 4" or so. I realized this while sitting on the couch which is my first row, listening to music. (one of the redesigns is a new screen, so without a screen right now, I have become reaquainted with my music collection.)

My primary movie viewing position is in the "second" row, which is a row of theater seats, and then there is a "third" row of theater seats on a riser. The first row couch gets little use during movies, but will now become my first choice for music listening.

So I realized that the couch in front of my "primary" seating position is blocking/absorbing some of the punch from the subs. Granted, I am 4' or so further away in the "primary" position, but I also feel that the sub punch is being absorbed by the couch in front.

So I have set out to raise my subs up by ~4" to get them a little more above the couch and into the line of sight of the back two rows.

My idea was to source a couple pieces of scrap concrete or granite slabs, pavers, flagstone etc. to put under the subs. But that would require a slab(s) of at least 18" x 20" x 4" thick. Pretty hard to find in my initial search.

Then I got to thinking I could just get 8 smaller blocks and place them under the 4 feet of each sub. That would be easier to source. I was then planning either way to put a larger, heavy piece of something on top of the sub to add more weight and firmly plant the cabinet on whatever I put underneath it.

Are there any drawbacks to going the 8 smaller blocks route? That would leave an airspace under the subs, but as they already sit on the four feet only, and they are front firing, sealed, I don't see any initial problems.

Or would it be better to remove the feet and try to find a larger slab to put under each sub? Placing them flush and flat on a larger slab?

All of this is going to be over carpet and pad over concrete floor.


Or are all choices mentioned equal?

I don't really feel like going through the time of building, gluing and screwing and filling with sand riser boxes.

Thanks.
ADDUpstate is online now  
Sponsored Links
Advertisement
 
post #2 of 8 Old 01-26-2012, 08:39 AM
Member
 
DiscoDuck's Avatar
 
Join Date: Mar 2009
Posts: 104
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Generally speaking sub bass is omni-directional so I'm not sure rasping them will do much. You might feel a little more impact if you move them closer to the corners. If have propped them up 4 inches with block of wood and like the change, go with it.
DiscoDuck is offline  
post #3 of 8 Old 01-26-2012, 08:44 AM - Thread Starter
Advanced Member
 
ADDUpstate's Avatar
 
Join Date: Mar 2011
Location: Perinton NY
Posts: 649
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Thanks. I can't move them closer to the corner due to OC triangle bass traps in the corners. I'm using AntiMode, and really like the sound, just trying to get it a little more in the line of sight.

Didn't know if there were any glaring problems with my thinking. For the couple bucks in pavers, I'm going to just try it and see. I guess the other solution is to get rid of the couch, or swap it out for a couple of theater seats that I could offset from direct line of the subs.
ADDUpstate is online now  
post #4 of 8 Old 01-26-2012, 08:47 AM
AVS Special Member
 
flickhtguru's Avatar
 
Join Date: Mar 2008
Location: Lebanon, PA
Posts: 2,458
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 105
If both your subs are in the front I'm guessing you didn't do the sub crawl. You might wanna try that to get the most even bass response across your whole room.

Also if you really want to raise them 4" I suggest making your own sub isolation/riser platform. Get a piece of 3/4" MDF paint it black or wrap it in black fabric of some sort and get 3-4" thick pieces of high density packing foam and make bricks out of them and glue them to the bottom of the MDF. I did this but only used 2" thick foam and it works great.

Shawn
flickhtguru is offline  
post #5 of 8 Old 01-26-2012, 11:15 AM
AVS Special Member
 
citizen arcane's Avatar
 
Join Date: May 2005
Location: At the gates of delirium
Posts: 2,281
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 34 Post(s)
Liked: 922
http://forum.blu-ray.com/subwoofers/...er-risers.html

Be sure to browse through the other 94 pages as there are a lot builds represented.

¿lɐɯɹou ǝq ʎɥʍ

citizen arcane is offline  
post #6 of 8 Old 01-26-2012, 07:25 PM
Senior Member
 
capricorn kid's Avatar
 
Join Date: Aug 2010
Location: Jonesboro, Georgia
Posts: 465
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Liked: 24
The only way to be sure is to place something under the subs about the same height you want to raise them. Listen to how they sound at your main seating position and if they sound good to you then buy or build something more permanent. The only way to be certain is to try it out.

Klipsch Synergy 3 speakers (LCR & surrounds)
dual Klipsch RW 12d
dual BIC PL-200
120" DIY 16:9 screen
Panasonic PT AX 200U projector
Panasonic BMP-BD35 blu-ray
Velodyne SMS-1
capricorn kid is offline  
post #7 of 8 Old 01-26-2012, 08:23 PM
AVS Special Member
 
tesseract67's Avatar
 
Join Date: Nov 2009
Location: Lincoln, NE
Posts: 2,507
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 15
The only way to know for sure is to do like this guy did... measure the difference. No meaningful difference was measured.

A good thread. http://www.avsforum.com/avs-vb/showthread.php?t=1349434

Where a riser really makes a difference, is in a three sub Geddes configuration, with one sub raised up over the center line of the room.

"Women and cats will do as they please, and men and dogs should relax and get used to the idea." -Robert A. Heinlein

Volunteer Moderator for the Chase Home Theater forum

tesseract67 is offline  
post #8 of 8 Old 01-27-2012, 07:41 AM - Thread Starter
Advanced Member
 
ADDUpstate's Avatar
 
Join Date: Mar 2011
Location: Perinton NY
Posts: 649
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Thanks for the input.

I'm going to get up and running on REW, at least basic tests, this weekend.
ADDUpstate is online now  
Reply Subwoofers, Bass, and Transducers

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off