Tiny Basement Mixing Room Woes

Plans and things, layout, style, where do I put my near-fields etc.

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epstudio
Posts: 45
Joined: Wed Dec 08, 2010 5:43 pm
Location: Grande Prairie AB, Canada

Re: Tiny Basement Mixing Room Woes

Post by epstudio »

So onto some construction questions... I went back to my hanger design and changed the orientation to increase total surface area... they are still at 40 degrees just turned the opposite way.

Anyone see an issue with the hangar orientation?
Hanger Orientation.jpg
Regarding the treatment for the front of the Hanger Cavity, my initial plan was to fill the front face completely with Roxul (covered in fabric) but reading through other peoples builds and seeing different techniques I'm curious if there is any acoustical advantage to leaving some space at the top or bottom?

As for the solid core Door... My initial plan was to install an acoustic panel of 3" thick Roxul in a frame covering all exposed solid wood... to try and mimic the treatment of the Hanger Cavity and remove that hard reflection. But now I'm thinking I should actually double that up and go 6" of Roxul to ensure no waveforms are bounced back into the room...

Should I completely cover the front of the Hanger Cavity with Roxul or leave a gap at the top and/or bottom?

Should I mirror the treatment on the door to be identical to the complementary angle on the right side of the Hangar Cavity? Should I use 6" of Roxul? Or would 3" be sufficient absorption on this solid surface to minimize and absorb most of the reflected sound
Hanger Cavity Face Plan.jpg
Thanks for any comments or advice! Everyone's time and input is greatly appreciated!!

Lee
epstudio
Posts: 45
Joined: Wed Dec 08, 2010 5:43 pm
Location: Grande Prairie AB, Canada

Re: Tiny Basement Mixing Room Woes

Post by epstudio »

Now that I'm almost in Hanger construction mode, I'm wondering if it would be beneficial to remove the superchunks from under my speaker soffits and put Bass Hangers there instead? It's not a huge space, but I will definitely have some left over Homasote with no where for it to go... Unless maybe I put it on the roof above the cloud instead of just cloth up there?

Should I replace these superchunks with Bass Hangers? Would the difference be enough to justify the hassle it will be to do?
Soffit S Chunk 1.JPG
Current Superchunks in existing soffits (note this pic is really old and not from my new build, however the soffits haven't changed)
Soffit S Chunk 2.JPG
Thanks Gang! :wink:

Lee
epstudio
Posts: 45
Joined: Wed Dec 08, 2010 5:43 pm
Location: Grande Prairie AB, Canada

Re: Tiny Basement Mixing Room Woes

Post by epstudio »

Hey Studio Land!! Here's my latest REW files with the Walls and Hanger Cavity fully stuffed and Ceiling 60% stuffed (can't finish the ceiling stuffing until I build the supply air hvac silencer...) Have a look! It made a significant improvement (as to be expected) compared to the empty room measurements.

Walls and Ceiling Stuffed:
https://drive.google.com/file/d/18VIHTO ... sp=sharing

Empty Room:
https://drive.google.com/file/d/1wr8FQ0 ... sp=sharing

8)

Happy Weekend!

Lee
Gregwor
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Re: Tiny Basement Mixing Room Woes

Post by Gregwor »

That desk looks unreal!

I think the superchunks under your speakers will be fine. As for the hangers, I would probably consider facing them with some pyramid shaped units like John's designed for this ceiling. which would help your time domain behave as intended.

Greg
It appears that you've made the mistake most people do. You started building without consulting this forum.
epstudio
Posts: 45
Joined: Wed Dec 08, 2010 5:43 pm
Location: Grande Prairie AB, Canada

Re: Tiny Basement Mixing Room Woes

Post by epstudio »

Greg! My man! thanks for the compliment on the desk it is absolutely unreal :yahoo: :D
I would probably consider facing them with some pyramid shaped units like John's designed for this ceiling.
I'm not sure which design you are referring too but I like what I'm hearing :lol: :twisted: :wink: ... did you have a link to his design or can you please elaborate Greg?

Thanks!!!

Lee
epstudio
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Joined: Wed Dec 08, 2010 5:43 pm
Location: Grande Prairie AB, Canada

Re: Tiny Basement Mixing Room Woes

Post by epstudio »

Is this the pyramid concept you were referring too Greg?

http://www.johnlsayers.com/phpBB2/viewt ... mid#p11298

pyramid wall.jpg
or is it actually the literal Pyramid diffuser/absorber shown here ?

http://johnlsayers.com/Recmanual/Titles/Acoustics1.htm
Diffuser.gif
Or is it a combination of both?? where you would put Pyramid diffusers/absorbers on a pyramid back wall design??

If it is the latter, I am certainly intrigued and must obsess about this now!! As more LF absorption is exactly what I'm after obviously, but now I have so many more questions ...

One of which is this: Looking at that Silva Studios design thread and other comments by John he says he always covers his roxul with a thin layer of plastic before fabric...
That's why I line all my rooms in plastic.
plastic_wrap.jpg
plastic ceiling.jpg
is this advised? Will it help to keep a little bit of HF "life" in my tiny room with soooo much bass absorption?

Please Help me Greg!!

:mrgreen: :mrgreen: :mrgreen:
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epstudio
Posts: 45
Joined: Wed Dec 08, 2010 5:43 pm
Location: Grande Prairie AB, Canada

Re: Tiny Basement Mixing Room Woes

Post by epstudio »

Found this post, are you thinking something more like this pyramid absorber/diffuser? I think I could incorporate something like this at least for part of the back wall

http://www.johnlsayers.com/phpBB2/viewt ... er#p129686
Diffusers_Pyramid.jpg
I wonder if I could make them out of my left over Homasote? Any thoughts on what the benefits would be using Homasote instead of hard wood for the actual pyramid surfaces?

[/color]
Gregwor
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Re: Tiny Basement Mixing Room Woes

Post by Gregwor »

You're right. The "pyramid absorber/diffuser" from John's page is exactly what I was describing. I've never built one before so I'm not sure how you'd go about building it short of cutting thin plywood and then face it with a veneer. The low frequencies will blow right through them and be tamed by the hangers in behind.

As for your plastic film covering your insulation, I'm on the fence about it personally. John recommends it but I'm concerned about it causing high frequency reflections. I should mention that I think film like that should be used to treat a room as long as it's not at first reflection points or at ear height. However, John is beyond pro and his rooms are amazing so you should just follow your gut and do what you think is best. Personally, I've worked in rooms where there is exposed insulation for many years and I'm okay sleeping at night. I might regret it when I get lung cancer or something in the future... only time will tell.

Greg
It appears that you've made the mistake most people do. You started building without consulting this forum.
anodivirta
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Joined: Fri Jan 04, 2019 6:41 pm
Location: Finland

Re: Tiny Basement Mixing Room Woes

Post by anodivirta »

I dont want to take this too far offtopic but;
Gregwor wrote: As for your plastic film covering your insulation
Greg
What about in Countries where we have to use vapor barrier?
placing insulation between layers of plastic is not usually recommended.
should the "real" vapor barrier be removed or does this platic film have gaps in some places so it breaths and this isnt really an issue?
epstudio
Posts: 45
Joined: Wed Dec 08, 2010 5:43 pm
Location: Grande Prairie AB, Canada

Re: Tiny Basement Mixing Room Woes

Post by epstudio »

Hi anodivirta, not off topic at all thanks for chiming in!! My first thought would be, as long as this isn't an exterior wall you should be fine, you wouldn't want to have | exterior wall | vapour barrier | insulation | vapour barrier | but as long as there is a sufficient air gap and /or other building materials and not an exterior wall, my research suggests there should be no issues with trapped moisture...

But yes as you suggest if this was an exterior wall, I would ensure there was only one vapour barrier. Anyone else have more seasoned or practical advice? I believe there has been similar discussions in the construction forum... Not sure what a forum search would produce?
Last edited by epstudio on Sat Jun 06, 2020 4:45 am, edited 1 time in total.
epstudio
Posts: 45
Joined: Wed Dec 08, 2010 5:43 pm
Location: Grande Prairie AB, Canada

Re: Tiny Basement Mixing Room Woes

Post by epstudio »

You're right. The "pyramid absorber/diffuser" from John's page is exactly what I was describing. I've never built one before so I'm not sure how you'd go about building it short of cutting thin plywood and then face it with a veneer. The low frequencies will blow right through them and be tamed by the hangers in behind.
Sweet! Thanks so much Greg! I’ve been doing a ton of research on the pyramid diffuser / absorber and it seems the thickness and density (mass) of the pyramid faces lowers the absorber’s frequency but I guess in this case I shouldn’t be too concerned about that?? Given the fact that the hanger cavity itself will be doing all the trapping as you surmise... I’m going to draw up a design and post it here for discussion! :idea:
Personally, I've worked in rooms where there is exposed insulation for many years and I'm okay sleeping at night.


Yes, I’m going to wait before worrying about restoring any high frequencies until all the bottom end is controlled and in line - I agree I’ve never been concerned about exposed mineral wool either, just the room being too dead! I’ll let room measurements speak to that I guess.

On another note... I’ve got my first hanger built and installed!! Woohoo! I’m stoked on my hanger design it is working perfectly!! Check it out! :yahoo: Now only 9 more to build!! :horse: :wink: :lol: :P :cry: :roll:

First pic is the spacing and sizing from sketchup to make the whole thing fit and nail the 40 degree angles...

HANGER DIMS.JPG
HANGER 0.JPG
HANGER 1.JPG
HANGER 2.JPG
HANGER 3.JPG
HANGER 4.JPG
HANGER 5.JPG
HANGER 6.JPG
HANGER 7.JPG
HaHaHa I love it when a plan comes together!! Can't believe I'm finally making treatment progress.. So much effort -- It's super exciting now !! :D Thanks again for all the input and help, especially you Gregwor!

Lee
epstudio
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Joined: Wed Dec 08, 2010 5:43 pm
Location: Grande Prairie AB, Canada

Re: Tiny Basement Mixing Room Woes

Post by epstudio »

Alright! Here's some hanger update pics... It is taking way longer than planned but they are making a profound audible difference in the room already and I'm only 4 hangers in!

Here is the jig I made to help bisect the 3" roxul -- It works really well! :idea: :o 8)
HANGER 8.JPG
HANGER 13.JPG
Here is Hanger # 2 and # 3
HANGER 15.JPG
HANGER 9.JPG
HANGER 10.JPG
Hanger # 4 which is probably the largest I'm going to be able to fit at 32" wide
HANGER 12.JPG
HANGER 11.JPG
Using aircraft cable tensioned between two eye hooks has worked out great for the hanging system, the bass hangers themselves are very easy to swing (good fulcrum) so hopefully that will translate into maximum efficiency of absorbtion! Can't wait to finish off the other 6 pieces!! :roll:

Lee
epstudio
Posts: 45
Joined: Wed Dec 08, 2010 5:43 pm
Location: Grande Prairie AB, Canada

Re: Tiny Basement Mixing Room Woes

Post by epstudio »

So I got my pyramid diffuser/reflector/absorber sketched... Not a lot of specific information available regarding how to design or build these things so I'm relying on input from you guys to help me through this!!

Here is the front side of the hanger cavity and the door covered with the maximum number of pyramids I can fit in a simple reversing pattern... Any suggestions on orientation are welcome as I just arranged them to fit the space and in reference to other manufacturer's recommendations.
Pyramid Diffuser front.jpg
Here is a shot looking at the back of the diffuser through the hanger cavity for reference.
Pyramid Diffuser back.jpg
The dimensions of the pyramid were determined by using "golden ratio triangles" for the sides as all of my research pointed towards this being the most effective design theory for this type of geometric diffuser although to be clear by definition this shape really only offers wave reflection as opposed to true specular diffusion... :cry: :|

Here's a shot from the top where you can see the Pyramid shapes a little better...
Pyramid Diffuser Top.jpg
I am wondering what the most effective approach is going to be in terms of "feeding" the low frequencies into the bass hanger cavity... From my research, filling the pyramids with insulation will dampen them and offer not only reflection of the high frequencies randomly back into the room but also add certain amount of wide Q low frequency absorption... I am planning on stuffing each pyramid with roxul like this:
Pyramid Diffuser Roxul.jpg
With my thoughts being that as the low frequency waveform penetrates the Pyramid and hits an initial mass of insulation some energy will be dissipated right away leaving less low frequencies for the hangers to absorb...

Can someone please chime in and validate or dispute this hypothesis??

As always, thanks again for any interest or comments on my build... I know the moderators are swamped so I really appreciate conversation or feedback from anyone on the forum! You guys are really the best!!

:thu:

Lee
Gregwor
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Re: Tiny Basement Mixing Room Woes

Post by Gregwor »

Good work Lee! That's exactly how I pictured it. I think you're designing them well and unless someone else chimes in saying that we're wrong, I think you're on the right track and should continue on!

Exciting!

Greg
It appears that you've made the mistake most people do. You started building without consulting this forum.
epstudio
Posts: 45
Joined: Wed Dec 08, 2010 5:43 pm
Location: Grande Prairie AB, Canada

Re: Tiny Basement Mixing Room Woes

Post by epstudio »

Woohoo!! :yahoo: Thanks for your response Greg!

I am going to finish all of the bass trapping and take measurements before I start adding any Diffusion/Reflection control (i.e soffit wings, and pyramid back wall...) to be certain I have maximized the low frequency treatment and am happy with the result of the room's "fully absorbed" state.

To that end, I really can't believe how effective these bass hangers are in my tiny room! The bottom end is audibly tighter with improved clarity and extended response... and I'm only half done these devices!! It's crazy how much square footage I have actually been able to squeak out of my very compact hanger cavity -- with the largest hanger at 3 feet wide! Once I finish the last 5, I will have utilized FOUR 4x8 sheets of Homasote and at least 120 sq feet of Roxul just on the hangers alone! It's crazy... :!: :D :lol: :shock:

I will keep taking pics and updating the thread with my progress which is painfully slow right now, but progress is being made which is a great thing... Thanks again for your help and encouragement Greg! Your time and input is significant and greatly appreciated as always!

Lee
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