Filled riser or vented - AVS Forum | Home Theater Discussions And Reviews
Forum Jump: 
 6Likes
  • 2 Post By BIGmouthinDC
  • 1 Post By BIGmouthinDC
  • 2 Post By markmon1
  • 1 Post By markmon1
 
Thread Tools
post #1 of 14 Old 06-16-2019, 04:04 AM - Thread Starter
Member
 
elitemikes's Avatar
 
Join Date: Jul 2011
Location: Haymarket, VA
Posts: 148
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked: 22
Filled riser or vented

I'm nearing drywall completion of my room. Hoping to have the room ready for primer by the end of this week. I've read various threads about venting the riser and others about building it solid. I'm leaning more towards solid as I don't' want to mess with trying to "tune" the thing. If i go solid, do I have to fill the cavities 100% with sand? Can I rely on some sand with insulation?
elitemikes is offline  
Sponsored Links
Advertisement
 
post #2 of 14 Old 06-16-2019, 04:34 AM
HOME THEATER CONTRACTOR
 
BIGmouthinDC's Avatar
 
Join Date: Jan 2003
Location: Northern VA
Posts: 31,642
Mentioned: 414 Post(s)
Tagged: 5 Thread(s)
Quoted: 5553 Post(s)
Liked: 5145
What is the size of this riser and are you planning any sources of vibration in or on the riser? Very few risers require sand. Stages usually benefit from sand. Multiple layers of decking with Roofing felt or Green Glue will help keep the riser quiet.
elitemikes and JRock3x8 like this.

Last edited by BIGmouthinDC; 06-16-2019 at 05:06 AM.
BIGmouthinDC is offline  
post #3 of 14 Old 06-16-2019, 05:33 AM - Thread Starter
Member
 
elitemikes's Avatar
 
Join Date: Jul 2011
Location: Haymarket, VA
Posts: 148
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked: 22
I do plan on keeping the rear sub on it. The riser will be roughly 8' x 13' x 8.25". I'm planning on having taller seats in the back so the rise should be fine for me. An 8.25 " rise matches the rest of the steps in the home so i figure I'll keep it consistent. If I absolutely need a few more inches of rise I can get it by stacking some plywood then creating a gentle slope.

I was planning on doing 2x8s 12" oc with 1 inch of plywood (double half inch).
elitemikes is offline  
Sponsored Links
Advertisement
 
post #4 of 14 Old 06-16-2019, 05:48 AM
HOME THEATER CONTRACTOR
 
BIGmouthinDC's Avatar
 
Join Date: Jan 2003
Location: Northern VA
Posts: 31,642
Mentioned: 414 Post(s)
Tagged: 5 Thread(s)
Quoted: 5553 Post(s)
Liked: 5145
You may want to create a small area under the base of the subwoofer that you fill with sand, fill the remainder of of the riser with the cheapest fiberglass insulation you can find. If you are building on concrete, lay down some roofing felt first and you can skip using PT lumber. If you are doing two layers you might just as well use 3/4. The labor is the same and the up charge for plywood is minimal. That is unless you have an inspector with a tape measure who thinks the step up is too high.
elitemikes likes this.
BIGmouthinDC is offline  
post #5 of 14 Old 06-16-2019, 05:57 AM
AVS Forum Special Member
 
markmon1's Avatar
 
Join Date: Dec 2006
Posts: 5,525
Mentioned: 102 Post(s)
Tagged: 0 Thread(s)
Quoted: 4661 Post(s)
Liked: 2955
People waste these great opportunities to turn the riser into a great sub box and instead fill them with sand

Video: JVC RS4500 135" screen in pure black room no light, htpc nvidia 1080ti.
Audio: Anthem mrx720 running 7.1.4, McIntosh MC-303, MC-152, B&W 802d3 LR, B&W HTM1D3 center, B&W 805d3 surround, B&W 702S2 rear, B&W 706s2 x 4 shelf mounted for atmos, 2 sub arrays both infinite baffle: 4x15 fi audio running on behringer ep4000 + 4x12 fi audio running on 2nd ep4000.
markmon1 is offline  
post #6 of 14 Old 06-16-2019, 06:02 AM
HOME THEATER CONTRACTOR
 
BIGmouthinDC's Avatar
 
Join Date: Jan 2003
Location: Northern VA
Posts: 31,642
Mentioned: 414 Post(s)
Tagged: 5 Thread(s)
Quoted: 5553 Post(s)
Liked: 5145
Quote:
Originally Posted by markmon1 View Post
instead fill them with sand
I've been in 50+ home theaters only one had the riser partially filled with sand.
BIGmouthinDC is offline  
post #7 of 14 Old 06-16-2019, 06:08 AM
AVS Forum Special Member
 
markmon1's Avatar
 
Join Date: Dec 2006
Posts: 5,525
Mentioned: 102 Post(s)
Tagged: 0 Thread(s)
Quoted: 4661 Post(s)
Liked: 2955
Quote:
Originally Posted by BIGmouthinDC View Post
I've been in 50+ home theaters only one had the riser partially filled with sand.
Just as much of a waste to leave them empty and put a boxed subwoofer on top of them. Most risers are big enough to even be considered infinite baffle.

Here's how you should use a riser



This one took 2 Fi 18" IB3s.



You get the ultimate in tactile feeling from the subs and don't have any issues with bass NULLs as the bass originates from your position.
Attached Thumbnails
Click image for larger version

Name:	ib12s.jpg
Views:	102
Size:	1.27 MB
ID:	2580694   Click image for larger version

Name:	ibsubsinplaltformholes.jpg
Views:	101
Size:	210.0 KB
ID:	2580696   Click image for larger version

Name:	ibsubsinplaltformfinished.jpg
Views:	101
Size:	115.8 KB
ID:	2580698  
elitemikes and BIGmouthinDC like this.

Video: JVC RS4500 135" screen in pure black room no light, htpc nvidia 1080ti.
Audio: Anthem mrx720 running 7.1.4, McIntosh MC-303, MC-152, B&W 802d3 LR, B&W HTM1D3 center, B&W 805d3 surround, B&W 702S2 rear, B&W 706s2 x 4 shelf mounted for atmos, 2 sub arrays both infinite baffle: 4x15 fi audio running on behringer ep4000 + 4x12 fi audio running on 2nd ep4000.
markmon1 is offline  
post #8 of 14 Old 06-16-2019, 06:11 AM - Thread Starter
Member
 
elitemikes's Avatar
 
Join Date: Jul 2011
Location: Haymarket, VA
Posts: 148
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked: 22
Quote:
Originally Posted by markmon1 View Post
People waste these great opportunities to turn the riser into a great sub box and instead fill them with sand
I just want the smoothest bass possible, no delayed tactile response. I don't need/want the floor vibrating. I know there is a long thread about venting and it seems to be more trouble than it's worth trying to get it just right.
elitemikes is offline  
post #9 of 14 Old 06-16-2019, 06:13 AM - Thread Starter
Member
 
elitemikes's Avatar
 
Join Date: Jul 2011
Location: Haymarket, VA
Posts: 148
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked: 22
Quote:
Originally Posted by markmon1 View Post
Just as much of a waste to leave them empty and put a boxed subwoofer on top of them. Most risers are big enough to even be considered infinite baffle.

Here's how you should use a riser



This one took 2 Fi 18" IB3s.



You get the ultimate in tactile feeling from the subs and don't have any issues with bass NULLs as the bass originates from your position.

Do you have any pre-carpet construction photos. What you did is way outside of my budget down the home stretch
elitemikes is offline  
post #10 of 14 Old 06-16-2019, 06:17 AM
AVS Forum Special Member
 
markmon1's Avatar
 
Join Date: Dec 2006
Posts: 5,525
Mentioned: 102 Post(s)
Tagged: 0 Thread(s)
Quoted: 4661 Post(s)
Liked: 2955
Quote:
Originally Posted by elitemikes View Post
Do you have any pre-carpet construction photos. What you did is way outside of my budget down the home stretch
The install that has 2x18's in it, the total cost was:
$274 x 2 for the speakers
$329 for the amp.
That's $877 total.

The quality of the sound is through the roof. Infinite baffle is some of the deepest, cleanest bass with no boominess. I bet you couldnt beat it for under $10k in boxed subs. Because these were infinite baffles not sealed boxed enclosures, the construction of the platform does not need any special work done. It's just a typical plywood platform with open air underneath. Probably not even fully air tight. There's no venting, no tuning, no porting. All you need is enough air space inside the platform to qualify as an infinite baffle and the proper infinite baffle drivers. These subs hit 5hz flat.

Oh also because they're firing right into you, you can turn the bass way down from where it might normally be and still feel just as satisfied without shaking the entire house down. Because they're originating in your position you don't need other subs around the room to eliminate NULLs. You are at the source of the sound.
plain fan likes this.

Video: JVC RS4500 135" screen in pure black room no light, htpc nvidia 1080ti.
Audio: Anthem mrx720 running 7.1.4, McIntosh MC-303, MC-152, B&W 802d3 LR, B&W HTM1D3 center, B&W 805d3 surround, B&W 702S2 rear, B&W 706s2 x 4 shelf mounted for atmos, 2 sub arrays both infinite baffle: 4x15 fi audio running on behringer ep4000 + 4x12 fi audio running on 2nd ep4000.
markmon1 is offline  
post #11 of 14 Old 06-16-2019, 08:03 AM
AVS Forum Special Member
 
SteveCallas's Avatar
 
Join Date: Jun 2004
Posts: 8,030
Mentioned: 38 Post(s)
Tagged: 0 Thread(s)
Quoted: 744 Post(s)
Liked: 686
I tend to agree - any future theater I build will utilize the riser as a subwoofer enclosure
SteveCallas is offline  
post #12 of 14 Old 06-16-2019, 08:43 AM
AVS Forum Special Member
 
LastButNotLeast's Avatar
 
Join Date: Feb 2007
Location: 08077
Posts: 9,664
Mentioned: 67 Post(s)
Tagged: 1 Thread(s)
Quoted: 2367 Post(s)
Liked: 1993
That would be a BOSS:
https://www.avsforum.com/forum/19-de...y-theater.html
Michael

Did you really need to quote that entire post in your reply?
Welcome to AVS - Get out while you still can!
Don't guess, measure: https://www.avsforum.com/forum/91-au...l#post22789786
LastButNotLeast is offline  
post #13 of 14 Old 06-16-2019, 09:13 AM
AVS Forum Special Member
 
SteveCallas's Avatar
 
Join Date: Jun 2004
Posts: 8,030
Mentioned: 38 Post(s)
Tagged: 0 Thread(s)
Quoted: 744 Post(s)
Liked: 686
I have 4 BOSS systems in my theater, those are a different animal. I meant using the riser as a traditional subwoofer enclosure as was shown above my post - subwoofers are usually the biggest pieces of gear in the room, and risers tend to be quite large - combine them to kill two birds with one stone. Still put subs in the front of the room, but use the riser subs additionally.

BOSS is AMAZING for tactile, i love them and they single handedly improved my theater experience, but for pressurization and spl you still need traditional subs too.
SteveCallas is offline  
post #14 of 14 Old 07-05-2019, 07:00 AM - Thread Starter
Member
 
elitemikes's Avatar
 
Join Date: Jul 2011
Location: Haymarket, VA
Posts: 148
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked: 22
I finished my riser early this morning, unfortunately i realized i made 2 mistakes. Both can be fixed but they both had me smacking my head. Wife was out of town for the holiday weekend with the kids so I'm trying to move fast.

First issue. My nosing is not an even depth all the way across the riser. Right side has me at 1.25" which is max allowed. Left side has me at just over 1.5" I can fix this 2 ways. Completely remove the nosing since it's not required by code, or fix the depth. Fixing the depth will make it difficult to round the edge after the fact, which probably isn't needed with carpet anyways. This happened because I made an assumption that my riser was square (very dumb) and I didn't catch it until multiple sheets were down.

2nd issue. I forgot to run an outlet behind my sofa. I decided against putting floor outlets on top of the riser because I have plenty of outlets on the wall, but that made me forget about one on the face of the riser. I'm not going to try and center one at this point. I just need to be a few feet off of my light. With any luck I can do this without having to make another hole just to drill. I'm not very confident in that though. I'll probably have to make at least 1 punch out to be able to drill.
elitemikes is offline  
Sponsored Links
Advertisement
 
Reply Dedicated Theater Design & Construction

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