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Post by goonstopher on Mar 2, 2015 8:31:44 GMT -7
I was able to pick up 4 AE IB15HT woofers but didn't think through my project fully after seeing the deal and getting impulsive.
I am sure this will never be ideal but maybe it can be made to work.
I have a large-ish walk in closet that is an old converted entance way I believe.
It is under a stairwell partially and I estimate internal volume to be around 180-200 after taking out the volume of the things in the closet.
The small size isn't my main concern... I am worried about the thin walls.
The front/room facing side is only 1 layer of drywall through the whole middle (top and bottom are 2 layers - one inside closet one in room.)
Also the stairs that cut through hald the closet are only covered by 1 layer or drywall through most and part doesn't even have that (that part can be closed off though, is inside a crawl space...but i like the added area since I am cutting this close/small).
The rear and 1 side wall are a little thicker but not much... The right wall is thick and has a window which can be opened.
I was hoping I could get by with cutting the drywall on the front/room side and putting mdf over that entire wall/space that had only 1 layer.
I would then like to have 2 15's on each side of the close door into this mdf.
Would a double layer of mdf here be enough to block the backwave from washing out the front?
How much to I need to build up the back and stairwell side?
If this can possibly work I will need more help with the modeling... When I try my models say that regardless of size or wattage, these speakers can only be used to 29hz... Even with 150w at 25hz it says they are past xmec
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Post by ThomasW on Mar 2, 2015 11:56:51 GMT -7
I'm sure the description of the room makes sense to you but it's a bit confusing to me. That's why we ask people to post pics or floor plan drawings.
Nothing wrong with your modeling, what you're getting is typical for those drivers. Remember those sims are anechoic models so they don't factor in placement or room gain. This means you'll certainly have output below 29Hz, IB subs just need less power as the frequencies being played go lower. You'll also need EQ because those AE drivers have a VERY Stiff suspension
Any place you can stiffen up the wall will be helpful to the cause. Under no circumstances will the back wave 'wash out' the front wave. Things just don't work that way in the real world.
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Post by goonstopher on Mar 2, 2015 13:13:30 GMT -7
I'm sure the description of the room makes sense to you but it's a bit confusing to me. That's why we ask people to post pics or floor plan drawings. Nothing wrong with your modeling, what you're getting is typical for those drivers. Remember those sims are anechoic models so they don't factor in placement or room gain. This means you'll certainly have output below 29Hz, IB subs just need less power as the frequencies being played go lower. You'll also need EQ because those AE drivers have a VERY Stiff suspension Any place you can stiffen up the wall will be helpful to the cause. Under no circumstances will the back wave 'wash out' the front wave. Things just don't work that way in the real world.
The only facts about the room that really matter (I dont have pictures with me) are related to wall thickness Do I need more than a double mdf baffle for the front "wall" (ie can that whole "wall" the baffle is on be done in MDF?) On the side walls - Should I add a second layer of drywall or cement board? Also - The size will be small for the VAS but I plan to add some sealed subs and use something like minidsp to allign them. Hoping for 3 sealed 18's in 24" cu behind the mlp... Then will have killer bass with no boxes in the room. |
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Post by ThomasW on Mar 2, 2015 14:42:31 GMT -7
Do I need more than a double mdf baffle for the front "wall" (ie can that whole "wall" the baffle is on be done in MDF?) Depends on why you're doubling the mdf. Are the drivers going to be mounted in a manifold or on the wall?. If they're going on the wall 2 layers of mdf is inadequate, the wall will vibrate excessively. If the drivers are going to go in a manifold and the double mdf is to cut down sound moving into the rest of the house the mdf will be somewhat beneficial. Again what's the goal? Low bass walks through anything less than 4" concrete or 6"- 8" solid wood. |
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Post by goonstopher on Mar 2, 2015 21:04:30 GMT -7
The mdf would be to keep the back wave out - it would be the wall.
For the other walls I was just hoping to insulate some - If I take out a fair part of it I dont need to block it all...
It sounds like my project MIIIIGHT work...
The "box" size will be just under 4xVas... I guess it's still worth doing...
I can open the window... If its not too late... Maybe have an EQ setting for window open and windows closed...
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Post by goonstopher on Mar 3, 2015 7:23:14 GMT -7
Its very yard to tell if i will be ok with my "box" size.
I believe I have 3x vas (conservatively) though it may be more. The area is just shaped odly.
The good part (I hope) is that there will be clothes hung up at the rear to act as "stuffing"...
Another thing, my ib15's are used so the suspension doesn't see stiff (I come from the high excursion, high power world of the jtr captivator...sooo... I am use to STIFF woofers)
Should I use 2 array setup (2x2) on alternate sides of the door (basically 20" appart) so that the rear wave is aimed back at them?
Will the SQ be poor because of the high Q?
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Post by ThomasW on Mar 4, 2015 7:59:49 GMT -7
I believe I have 3x vas (conservatively) though it may be more. The AE drivers are not designed to operate in a box that small. It's possible you may run into thermal limiting and that's not a good thing for IB drivers Clothing isn't an effective damping material Sorry I can't visualize what this would look like. Don't really know, it's certainly far from optimal |
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Post by goonstopher on Mar 4, 2015 14:03:15 GMT -7
I believe I have 3x vas (conservatively) though it may be more. The AE drivers are not designed to operate in a box that small. It's possible you may run into thermal limiting and that's not a good thing for IB drivers Clothing isn't an effective damping material Sorry I can't visualize what this would look like. Don't really know, it's certainly far from optimal Should I even continue with the idea considering all of this? I bought the woofers and would lose money selling them. My goal was to hide all subwoofer - I would have 2 "systems" of woofers. 1 would be this "IB" about 3 meters away and the other would be turning a alcove into a large array of sealer 18's (3 or 4) about 1 meter away. It sounds like maybe my plan is dead... |
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Post by ThomasW on Mar 4, 2015 15:56:29 GMT -7
They could be used to simply augment (flatten) the overall in-room response. That way they wouldn't be driven as hard as if they were trying to equal the output from the 18"s or augment the lowest frequencies.
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Post by goonstopher on Mar 7, 2015 15:27:49 GMT -7
They could be used to simply augment (flatten) the overall in-room response. That way they wouldn't be driven as hard as if they were trying to equal the output from the 18"s or augment the lowest frequencies. Did some more calculations on my ODD shaped closet... Looks like I have about 280cu/ft before subtracting for anything in it. Looks like 4x Vas should be possible BUT it doesn't seem like this is worth the effort because of the driver limitations and the steps I would have to do. I ran it in winisd and it looks like the IB15's are bad for using in an IB?  200w per driver hits 18mm excursion at 25hz and over 33mm at 15hz which would destroy the drivers. 100w per driver hits 18mm excursion at 20hz and 24mm at 15hz and certainly could destroy the drivers (almost 27mm at 10hz) How are the being used in IB if they aren't capable of playing below 25hz? Is it worth all of this (Below)?I know bass WILL get through my walls... They are thin and I can't build them SUPER think to actually stop it. Is there any hope of at least bringing the leaking down?? I would need to make some attempt to keep sound in ad the back of the close is open to a communal hallway. I can be loud but need to keep it from being painful. This means I need to treat: 1. Stairs - Run through and account for the long side of a triangle approx 33" deep; 96" wide, 105" tall (not a full traingle but just givin scope_ There is basically nothing under the wood under the stairs. most of it has a layer of drywall but thats it. 2. Rear wall and small side wall - Rear wall is least important and hardest to do because I am NOT taking down the closet set so there will be some gaps 3. Ceiling - This will be a pain... 4. Floor - Another pain 5. Inside/woofer side wall (into room) Stairs Plan/idea- Cut down the dry wall and put up corner dampening/isolation clips
- mount 1x4's onto the clips/stairs as "beams"
- take 2 layers of drywall and put green glue between.
- hand this onto the isolates "beams"
Rear/side walls PlanBiggest issues are avoiding the "triple leaf" effect and working around a closet setup (full back access... just tough to slide and cut smaller pieces to fit in there.) - Use a layer of thick felt as the first/isolation layer (over green glue for cost and any gaps or future removal) - there is an article about this working as a "poor mans" isolation trick and it also should mitigate the triple leaf effect.
- add/hang 2 layers of dry wall, possibly with green glue between
Ceiling... "Plan" (kind of stumped...) Its a small area so may use the same ideas as the rear/side walls. Floor Plan/ideaBuilding up the floor a bit wouldn't be a bad idea to ensure the door has something to seal against. - Try to seal any obvious gaps/leaks in the old hardwood floor (old school plank) with accoustic caulk or whatever
- Add a layer onto the floor - Little torn on what this first layer would be. Most logical seems to be felt and single layer MDF
- Buy a carpet remnant big enough and carpet the faux-floor also using carpet padding and doing it just like it was the real floor
Front wall idea - this is the baffle wall- strengthen the closet door frame adding cross beams (like 2x4's) to make sure it is coupled to load bearing beams (it is sort of floating on the sides now and only 1x8 plank connecting on top)
- re-build this whole wall - Cut down dry wall, isolation clips on the new cross beams and hang double dry wal
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Post by ThomasW on Mar 8, 2015 9:42:37 GMT -7
I ran it in winisd and it looks like the IB15's are bad for using in an IB? How are the being used in IB if they aren't capable of playing below 25hz? As I previously posted WinISD sims are anechoic. This means they don't factor in room gain. The drivers play significantly lower than 25Hz. If you look at any of the dozens of AE-IB build threads documented on the forum you'll final measurements of how low they play. Your other subs are going to play louder than the IB so the concern is keeping the combined output from all the subs contained. We aren't a HT design forum, I suggest you checkout AV Science they have a huge forum regarding how to design HT's |
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