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Black Cat Theater (Now going BIG!)

30K views 173 replies 48 participants last post by  BIGmouthinDC 
#1 ·
After months of lurking on this forum, I'm ready to start construction of the...



which is going to be constructed along with the rest of the basement:



The inside of the theater will be 20.5' x 15.6' x 8.5', but that doesn't include the bump-out in the back for the projector or the bump-out in the front for the center speaker and subs, which will be behind an acoustically-transparent 2.35:1 screen:



The theater is dimensioned assuming Lazboy Matinee seats and Klipsch THX Ultra2 speakers and I assume I'll get an SMX AT screen - I'll build everything else in the room...


I think I'm ready to pull the permit but, before I do, I was hoping to get a nod from you to go ahead. For the permit, I'll only use the entire basement layout picture above, which doesn't say much about the theater area other than where the walls are...and therein lies my first question - will I have enough sound proofing/isolation?


Specifically, note that the three poles (blue circles) and the concrete walls constrain my space. I'm very willing to let the interior walls be extra thick as it lets me stagger-stud one and double-wall the other, while hiding the PJ and rear speakers inside it. The walls against the concrete will be 2x4 framing with 2 layers of drywall with Green-Glue between. Also, note that the 2' wall near the front-left speaker will have its 2x4 studs laid flat, but it will still be DD+GG.


So, what do you think, do you see any issues with this design?


PS: in case you are wondering, I was down in the basement a few months ago looking things over and trying to come up with a name for the theater when I noticed my cat, who is black, lounging in the middle of the taped-out floor


Thanks,

Morphic
 
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#128 ·

Quote:
Originally Posted by BIGmouthinDC /forum/post/22028590


So we formulated a plan


BIGmouthinDC in his early days of home theater building, calculating how many staples it will take to complete the Arbor Oak Cinema

 
#130 ·

Quote:
Originally Posted by ozziegt /forum/post/0


I assumed you used this article as your starting point? Where do you think it fell short?

Yeap, in fact, I think I referenced that very article near the beginning of this thread. Looking at it again, I think it "falls short" in this paragraph:

Quote:
A typical room will need a 6´´ supply and comparable return. These ducts are a large cross section for sound to freely escape, regardless of the direction of airflow.

Because a single 6" supply and a single 6" return will each have too much FPM to be quiet while accommodating the ACH (air change per hour) needs for a 15'x21' room. See http://www.bravoav.com/articles/ht_hvac.pdf .


ACH = (CFM*60)/volume, thus CFM=(ACH*volume)/60. From the article, 6 ACH is recommended. Thus, CFM = (6*volume)/60 = volume/10. My room's volume is ~300 sq ft., so I need 300 CFM. 340 CFM is actually more than I need (6.8 ACH), but that was the next fan-size up gave me...


Remember, we want FPM to be close to 250, to be quiet. FPM = CFM / area (sq-ft). So, area = CFM/FPM = 340/240 = 1.42 sq ft. Note that two 12" ducts = 1.57 sq ft (room to spare), whereas two 8" ducts is only 0.7 sq ft. (not enough!)


BTW, I didn't know any of this until *after* hearing the air-turbulence (Starship Enterprise). I naively thought that a single 6" would be fine since the fan itself is 6" and, to a lesser extent, because Ted's article suggested that 6" was "typical". Oh well, life is full of learning experiences.
 
#131 ·

Quote:
Originally Posted by Morph1c /forum/post/22030364


ACH = (CFM*60)/volume, thus CFM=(ACH*volume)/60. From the article, 6 ACH is recommended. Thus, CFM = (6*volume)/60 = volume/10. My room's volume is ~300 sq ft., so I need 300 CFM. 340 CFM is actually more than I need (6.8 ACH), but that was the next fan-size up gave me...


Remember, we want FPM to be close to 250, to be quiet. FPM = CFM / area (sq-ft). So, area = CFM/FPM = 340/240 = 1.42 sq ft. Note that two 12" ducts = 1.57 sq ft (room to spare), whereas two 8" ducts is only 0.7 sq ft. (not enough!)

Isn't your volume going to be sq ft * ceiling height? So if you had 8' ceilings it would be 15x21x8 = 2520 cubic ft


6 exchanges per hour is 15,120 cubic ft / hr, which is 252 CFM.


edit: Ahh, so you have 10' ceilings, which is why you divided the volume by 10.
 
#132 ·

Quote:
Originally Posted by ozziegt /forum/post/0



Isn't your volume going to be sq ft * ceiling height? So if you had 8' ceilings it would be 15x21x8 = 2520 cubic ft

Sorry, I dropped a '0' there, it was suppose to be 3000 sq ft. It's just an estimate, as I gain some from the bump-out behind the screen...
 
#134 ·
I didn't have time this morning to post the 3rd update chapter. Here it is. This is about the new TOYS


Mark Halflick of AVS hooked Morph up with some goodies.


We had to test them (Obviously)

















For the record I've put together a few SMX screens and now a SeymourAV screen. The Seymour grommet fabric attachment is a lot easier, almost idiot proof. Just be sure you measure the diagonals of the frame and make sure it is square before attaching the fabric. This has also been an issue with SMX screens. If the measurements don't match loosen the corner brackets and make the screen square, tighten the brackets.


Enough play time, we wrapped it all back up and put in the "clean" room.

 
#138 ·

Quote:
Originally Posted by HopefulFred /forum/post/22035804


How did the carpet go?

This pic doesn't do justice - in person, the carpet is much more matchy-matchy with both the "straw" and "ochre" fabrics. The carpet has a very deep/rich tone, which pulls hard on the stained wood (see light tray).




I decided not to do the Bitterman/Sierrra after all, because it didn't feel soft, there was a potential for a pattern clash, and because it was 100% wool. This carpet is silky/plush, has no pattern, is synthetic, and has a life-time stain-removal guarantee. The field-color of this carpet is the same as the Bitterman/Sierrra, it only lacks the red-pattern... So now the big question is, how well my red-fabric chairs will look in this room? - with nothing to tie into, they have to stand on their own...
 
#139 ·

Quote:
Originally Posted by Morph1c /forum/post/22037451


So now the big question is, how well my red-fabric chairs will look in this room? - with nothing to tie into, they have to stand on their own...

I have the EXACT same chairs and I stopped just before GOM b/c I couldn't find a good fabric for the walls. Like you said .. they kind of have to stand on their own. I wish I had gone with a different color on the chairs for that reason... Great looking room so far. You are getting close.
 
#141 ·

Quote:
Originally Posted by pauleyc /forum/post/22049052


I have the EXACT same chairs and I stopped just before GOM b/c I couldn't find a good fabric for the walls. Like you said .. they kind of have to stand on their own. I wish I had gone with a different color on the chairs for that reason... Great looking room so far. You are getting close.

The chairs aren't tying in much yet, but I'm optimistic that the fabric and molding with do the trick. Should look something like this when done:

 
#142 ·

Quote:
Originally Posted by JVoth /forum/post/22049081


I saw the thread asking for calibration advice on this room and I also saw that speakers were installed. I searched through these pages but couldn't find what equipment you decided to go with except for the JVC RS-45 and the Seymour screen. What equipment did you decide to go with?

I got some Triad Silver OnWall surrounds and am repurposing my M&K 850s for the LCR. Sadly, my matching M&K 650s are sitting this one out since I felt that I needed bipoles. Also, it helps that the Triads are half the depth, so they don't stick out as much for people getting to/from the back row.
 
#144 ·

Quote:
Originally Posted by Morph1c /forum/post/0



I got some Triad Silver OnWall surrounds and am repurposing my M&K 850s for the LCR. Sadly, my matching M&K 650s are sitting this one out since I felt that I needed bipoles. Also, it helps that the Triads are half the depth, so they don't stick out as much for people getting to/from the back row.

I love my M&K 750 system. I'll be interested to hear from you how the Triads sound with the M&K's. What about subs, pre amp, amps, and all the other good stuff?
 
#145 ·

Quote:
Originally Posted by JVoth /forum/post/0



I love my M&K 750 system. I'll be interested to hear from you how the Triads sound with the M&K's. What about subs, pre amp, amps, and all the other good stuff?


The 850s are the wood-veneered version of the 750s, the drivers are identical. So far I don't notice any discolorizations between the M&K LCRs and the Triad surrounds, but I've yet to sit for a critical listening. I only just now configured my amp to know about each speakers distance and equalized their outputs so the sound the same for my prime listening positions (middle of the front row)


I've got a M&K MX-150. I might get another if there isn't enough bass in the room. We'll see...


I have a Marantz SR9200 receiver. I don't yet have a strong reason to upgrade it. Audussey would be nice, but I'll wait. One small issue is that all my speakers are currently 4-ohm whereas the SR9200 is 6-ohm. That said, I've read that the speakers are more like 6-ohm with an 80-Hz crossover, which I'm doing. I've also read reports from others running the SR9200 with 4-ohms and no issues. I'm going to watch my levels for a little while...
 
#146 ·
So my wife and I watched our first movie last night - a DVD from Netflix. The good news is that we watched the movie and it beat the heck out of watching on a computer screen (what we've been doing for the last few years). The bad news is that the PJ's controls became unresponsive as soon as the movie started (I wanted to zoom the 4:3 image a little). After the movie, we watched a little of the Blu-Ray Demo Disc and, again, I couldn't change the lens CIH. Giving up, I discovered that I couldn't even turn the PJ off - not via the remote or the button on the back on the PJ. I decided to leave it running all night and tackle it in the morning. So, this morning, after reading what other people have done, I unplugged it and let it cool done. Now it's functioning correctly again, which is a relief, but I'm very disappointed it happened and now am apprehensive about using it. I wonder if something on the DVD could've caused it, but I'm too scared to play the movie again, so we'll never know...
 
#148 ·
We are going to need to add a corollary to the old saying never hang your projector and screen before the room is done, Well the projector and screen is hung, but now armed with REW room measurement tools the audio and acoustical treatment side of the room is getting scrutiny and analysis before the fabric finishes and trim molding go up. So the corollary is never start actually measuring your rooms audio performance if you are in a hurry to finish the room.


I last saw Morph1c a couple of weeks ago when we picked up some sheets of Baltic birch, cut them in my shop and he was going to work on building a THT sub.
 
#149 ·
I'd like to see more pictures of how the electrical box cover came together and mounting scheme. I'm assuming that box cover will then be covered with a finished acoustical panel?
 
#150 ·
I think BIG's corollary applies, while I have watched a few things, the biggest delay by far is getting the sound where I want it before buttoning it up (i.e. stapling fabric in place). In case you haven't seen it already, this thread catalogs the testing we've done so far: We Built it, We've measured it, HELP US TWEAK IT - acoustics of the BLACK CAT . One update to that thread, I've now decided to only build one THT sub, at least for now, as I understand that one will completely own a room the size of mine.


Regarding the THT build, I installed panel #2 of the THT sub this morning. It's not an easy panel to get tight into the corner and now I have a hairline crack there. I think I'll just caulk the joint with PL like others have done...


In other news, I was able to pick up enough black FR701 GOM from fellow AVS member Snipe4Real to cover the panel under the screen. I was originally planning to use the Network/Ochre GOM there, but I think black/black might look better under the screen and, more importantly, the open weave pattern will provide a place for the air supply behind the screento vent out, which seems better than better using the screen as a filter
 
#151 ·


To address my bass needs, I decided to build a subwoofer - a 30.5"-wide THT ( Tuba HT ). It's total outside dimensions are 36" x 36" x 30.5" (23 cubic feet)


The bass it puts out is ridiculous. The seats in the theater shake. My wife two floors up said it felt like a monster truck was driving through our house. My brother said his balls vibrated



Here's a pic up it behind the screen - I outlined it in blue:




I've done new measurements with REW, which I'll be posting the the We Built it, We've measured it, HELP US TWEAK IT thread shortly


Stay tuned!
 
#152 ·
What is the status of your wall fabric?
 
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