CR Treatment and Tuning---The home stretch!!

[Soundman2020]

I just wanted to check that I couldn't use the 1" duct liner instead of 703. Hate to waste it ...Can you think of anywhere else to use it if not?

Afraid not. Not for this case. Higher density would be better, in this specific case, which is why I suggested OC705, if you can get it. But 703 is also OK.

We can use the duct liner in the soffits, though. Both the "soffits" above the slotted polys, but more importantly the speaker soffits. You are going to need quite a bit of insulation to fill those. We could even do an experiment, and see how it works for the hangers under the speakers: it's worth a try. Make one set of hangers normally, and one set with duct liner, then swap them out to see if there's a substantial difference.

For the "soffits" above the polys, I would cut the duct liner to the same shape as the floor of the soffit, and stack it up in layers. But first, what type of duct liner is it? Brand / code.... I'd like to see if it is suitable...

- Stuart -

[Stadank0]

Its the Johns Manville Linacoustic RC 1" R value 4.2.

How's about inside the soffit walls? Layered to depth of course...

You'll be happy to know that the insulation removal punishment is underway and possibly having the desired effect...

[Soundman2020]

Johns Manville Linacoustic RC 1"

That's fine, but not so good in the lows (to be expected: it's only 1" thick). So I'd recommend the following "fill" for the soffits above the poly's:

Starting from the front, and going back towards the wall:

Fabric finish --- cheap black light blocking fabric --- 3 mil plastic --- 2" OC703 standing up vertically, on edge --- horizontal layers of duct liner stacked up --- insulation in rear stud bays --- sheathing.

That should give you decent performance in the lows, and keep the highs nice.

You'll be happy to know that the insulation removal punishment is underway and possibly having the desired effect..

I figured you were about due for another "workout" like that! Glad you appreciate the effort...

The good news is that there's not much more insulation to do now... the bits above the doors, the soffits, and the cloud.


- Stuart -

[Stadank0]

Fun with floors...

[Soundman2020]

Fun with floors...

Looks pretty nice, actually!

Hint: Once the floor is done, get an old piece of carpet, flip it over (fluffy side down, rough side up), and cover your complete floor with that. That's to protect it from dropped tools, dropped materials, you falling off the ladder ...

Of course, you'll need to take that out for each REW test...

And speaking of REW tests, that flooring will probably change things slightly. No big deal, of course, but it will be interesting to see what it does.


- Stuart -

[Stadank0]

I figured it would, but that was inevitable..Got some throw rugs to put down when needed...

[Stadank0]

All done with that!!

20180219_174655.jpg

[Soundman2020]

Nice work! Nice choice in texture, too. Looks very elegant.


- Stuart -

[Stadank0]

[Stadank0]

It looks like you intend mdf on the ribs? I bought pine not noticing at first but might be able to return it.


Ohh, never mind. I an see in the model that it is...I can return the pine fortunately..

[Soundman2020]

Pine is fine, as long as it is good quality, fully dried, and won't warp in the future. I prefer MDF for this type of shaper rib, since it will keep it's shape over time without warping, twisting, bowing, etc. Good quality pine, or ply, or even OSB, would be OK too.

You'll need to work carefully at the thin point close to the outer end, as that's only about 1/2" wide, IIRC. Might need to beef that up with extra wood on both sides, to help keep it intact.

I'd suggest making one as a template first, then checking that it fits, all the way up and down the entire height, modifying as necessary, then using that to cut out all the others. Clamp them all together for the final sanding, to ensure that the all have the same shape, as much as possible.


- Stuart -

[Stadank0]

Definitely going to make a template... Pine might hold together better than MDF at 1/2 inch..hmmmmm.

The pine I have is fully kiln-dried so no worries there.. I'll think about it a bit. I have choices. That's good.

If I had to guess I'll probably have it done by Tuesday next week.

[Soundman2020]

If I had to guess I'll probably have it done by Tuesday next week.

Cool!

I'd suggest that you start at the middle and work outwards with the slats. So put up the first three slats on each side closest to the middle of the rear wall, REW test, then the next three on each side, REW test, etc. It might turn out that we don't need the last couple on the far ends, near the doors. I think we will need them, but just to save you the effort do it in steps.

Also, I don't know of you noticed, but I changed the pattern of the slats on the rear center section (the ones you had put up temporarily). Just reshuffling a bit, and taking out the thinner ones closest to ear height. So don't forget to change those too. You can make those permanent, if you want.


- Stuart -

[Stadank0]

It might turn out that we don't need the last couple on the far ends, near the doors. I think we will need them, but just to save you the effort do it in steps.

Hopefully they can go in because I think it will look weird if they're not there...

I'll make sure to check the slats thanks!

[Stadank0]

So now that you've created 18 separate compartments, do they need to be sealed from each other? Also, How exact do the vertical separator locations need to be?

Still spinning my wheels a bit, but hopefully momentum will pick up soon. I changed out the pine for 3/4 plywood on the framing. I'll still use pine on the face boards of course. Thinking things through definitely slows me way down!