AudioGrotto Build Diary

Well, basically its the fabric. I had not spec'ed fire rated fabric as a cost savings factor and also since this is really zoned a "home office" and not a commercial space. BUT, the reality is if I am using it in any commercial way, the liability is still mine regardless of zoning. Insurance is mine. If there were to be a fire and someone got hurt (let's hope not) I could get sued for having non-compliant fabrics in the space. Not worth it. By taking care of this now, my inspector won't shut me down during the final and make me take it all down and re-do it. That's the savings right there. BTW, my next door neighbor is also my inspector so I will not slip anything by him like this. Plus, I wouldn't want to. Code is there for a reason, a really good reason. Better to do it right the first time. Right, so here's the reality check for all us DIY'ers out there..... Burlap - No freekin' way. Goes up like a torch. Try it. Muslin - again, better used as a torch for exploring caves then above your head in upholstering the ceiling clouds. Velvet - gotta be fire retardant, treated in some way. Acoustic Foam - light it and see. :ahh: :asth: (I wasn't using any of this but thought it was worth mentioning) I'm going for Guilford of Maine stuff and some treated velveteen. There's a reason why all the studios are made out of Guilford. Yes, its acoustically transparent but its also Class A fire rated. The best rating. All of this is more expensive, but nothing compared to the expense of a lawsuit where someone got hurt in a fire. -ashley

Thanks. You are right, this is something each of us must always keep in the high part of our mind. After all, it's for our own good and the good of those in our care ;)

Hey Ashley, Before you go the Guilford route, check out the Acoustic Fabric section of Burch Fabrics in Michigan. The exact same stuff as Guilford and MUCH cheaper. Looks like their website is currently under reconstruction but their phone# is [removed] best, Joe

Just in case: http://www.burchfabrics.com/ that has a link that points to: http://showcasefabrics.com/

Thanks, Joe. I seem to remember talking to you about these folks a long time ago. They were in my browser favz. I've d'inked them an email to get some info. I'll report back. -ashley

Well, we are moving ahead. I have plans back from Wes which have the details of where the soffit wall goes and how to do the rear wall. Sweet. :jammin: But first, I am working on getting the ceiling panels further along, and also out of the way as they are taking up all the floor space. We were having all sorts of head scratching session trying to figure out how to hang these darn things safely. Have you priced hooks and stuff at Lowe's lately? Fuggetaboutit... :finger: However, Wes had something in that regard. Back in the rear dark corner of Lowe's, there lies a section of the store devoted to drop ceilings.... :mrgreen: Back there you can buy hooks that will go through two layers of 5/8" drywall in packs of 20 for around $2.50. Now that's more like it! 120 hooks and two spools of 1/8" hanging wire later, we are hanging the empty frames up to see how they'll look and get everything set before putting in the lighting, upholstering and stuffing them. Since we used metal framing, we had to pre-drill the holes to get the hooks through the 18 gauge metal. Problem...... the coarse threads of the hooks didn't feel quite secure enough just hanging in the metal. So we decided to add plastic anchors so as to snug those hooks and also fill the hole fully. This worked quite well. Just to be clear, the hooks are in the metal studs but also within the plastic anchors. This works well. I have piccies but just haven't got them out of the camera. Next post..... til then.... -ashley

I have the pics of the ceiling hanging process..... We set the panels on the floor and placed them, carefully lining them up with string lines and such. Then using a plumb bob we transferred marks up to the ceiling and strung lines using pushpins. Find a stud within the line and then mark out from there. Redundancy is the key to making sure these don't come crashing down years later. Re-plumb bob down to where the anchors go on the panels and put in the sister set of hooks. Wire and hang.... -ashley

More ceiling panel pics.... We have not hung the ones in the main control room since they need to hang relative to the soffit wall and that is now under construction. Soffit Wall next..... -ashley

OK, on to the soffit wall..... In trying to get a sweet spot that hits the mix position and the producer chair at back, the soffit wall is angled a bit and the speakers placed a bit higher. That makes for some tricky carpentry. We removed the existing soffit wall (my design) and started framing up the new one. The only issue we have run into thus far is concerning the center channel speaker. This is a giant PITA :horse: :horse: :cen: :cen: I bought a small PMC speaker the DB-1C in a center channel format to allow us to place the flatscreen at a reasonable position on the wall. Problem is I forgot the darn thing has a rear port!!!!! :cop: :cop: No soffit mount for this puppy. Anyone in the market for a PMC DB-1C? Absolutely mint cond..... PM me. Anyhow, I now need to figure how to mount my LB-1 in there as a center channel. Its a tall speaker and there is not enough room to get the box in the wall vertically so it will have to go on its side. By centering up the tweeter though, the whole box becomes off center in the wall. We will remedy this by creating a fabric scrim that covers the whole thing cosmetically. Right. Sorted. Piccies on the soffits.... Bass traps coming next. -ashley

Right. Now to tame some of that bass coming out of the soffits. The AB-1's spec down to 20Hz and they really do slam! I am obsessed with low end, hence the "bassman", plus I'm a bass player. I want the biggest bottom I can get, which is easy if you eat smoked brisket all the time!!!! We smoked a brisket yesterday and finished it off today.... WOW that's good. OK, enough of my big bottom, on to the traps.... These are simple panel traps made with a sealed wood frame, some rockwool and covered in with a single plywood sheet. For dimensions and tuning, refer to your local (or international) acoustic designer..... Anyhow, here's what they look like..... -ashley

More bass traps going in and rockwool over them..... -ashley

:shot: The soffit wall is coming along nicely. The carpentry is tricky since they have a slight angle to them. Fill with normal insulation and cover in two layers of drywall. we relocated the two electrical outlets into the soffit wall to meet code and get juice to the TV in the right spot. Conduit was installed to get wires to the TV and speakers. -ashley

Oh wow! Major advances! You are making me turn green with envy at the progress! :) It's looking good! - Stuart -

great job, I think you need wool those clouds! :D How high are your speaking (L and R) they seem really low?

Hello lillth, The speakers are PMC AB-1's and their tweeters are fairly high in the cabinet. They are aiming right at ear level. See the chair in the pic. The speakers actually point a bit down to ear level. Yea, I've run out of wool from those darn bass traps! :horse: :horse: Got another 10 bags on the way! -ashley

Treatment update: Progress continues in both control rooms getting the soffits finished and the rear wall stuffed plus some corner traps in the second control room. Piccies..... -ashley

We started to lay out pew pieces in the shape of the console to start thinking about its design. -ashley

:cen: On to a new subject: noise complaints from our neighbor during a particularly loud drum session this weekend. This guy was hitting the crap out of the drums! 105 to 110 dBC at the kit!!! At the inside of the large stained glass window, we read around 100 dBC. Outside the window, drums were 80-85 dBC. Their house is 5 feet from that window. I guess we have a problem now..... :cop: Well, :cen: :cen: :cen: :cen: :cen: :cen: :cen: :cen: :cen: :cen: :cen: :cen: :cen: :cen: :cen: :horse: :horse: :horse: Right, our neighbor happens to be a retired judge who specializes in property law and zoning. How's that for luck? Actually, he is a reasonable man and we are going to work this out. The drums are really too loud over there. So, help me figure out a way to knock another 20 dB from the sound coming out of the windows. The pics show it all. We can't really do glass block for two reasons: Historical preservation might not go for it even though these windows are on the side of the building and not part of the facade. A large glass block structure like this needs to be made from the 4" block and we only have barely 3.5" from the brick to the wood frame. So, my current plan is to see how much 1/2" tempered glass is going to cost in order to cover these 9' x 15' windows from the outside. Currently, there is a think (1/4") layer of plexiglass covering the stained glass. We would take that off and replace it with the 1/2" tempered glazing. I know laminate would be a couple dB better but the cost is more than double AFAIK. Thoughts? -ashley

Two things. What can you do on the inside of your window area to mitigate this issue? Simple things like drapes, plugs, etc. Would installing a dense glass panel over your neighbors window be helpful?

Well, let's think about it.... The big window is 15' tall and 9' wide. Anything on the inside to get a 20dB drop would be pretty massive. I don't think drapes are going to work. The plugs would have to be HUGE!!! and hard to move in and out. On his window, we are proposing putting on good storm windows to seal it up on his end. I just had a conversation with some friends here in the city and we are now thinking that glass block might be a possibility. I have some calls to make on Monday to find out about this. Glass block would definitely do the trick IMO. What is the STC of 4" glass block??? I can't remember... :roll: -ashley

Right, big hole. It just seems that you are going to confront this from many different angles for it to be effective. So small adjustments with your additional steps can start solving the concern.. Spending some money on the next door neighbors window, looking into tempered or laminated, might be better then a simple storm glass, as your last line of defense before sound enters his home. 4 inch glass block is rated at STC 44, give or take, but I don't know what the TL is and that is going to be important for your overall isolation.

I really like your soffit build Ashley, can you tell me how the wall doesn't create a triple leaf, since it seems as if you built the soffits against gb, and then went over them with gb?? I'm looking to do something similar.

Currently, there is a think (1/4") layer of plexiglass covering the stained glass. We would take that off and replace it with the 1/2" tempered glazing. I know laminate would be a couple dB better but the cost is more than double AFAIK.

1/4" Plexiglass? No wonder you have a problem! Plexiglass is less than half the density of normal glass. 1/2" of tempered glass would be roughly 4 times the mass of the existing plexiglass, so by mass law alone you should get around 12 dB extra isolation, just from replacing that 1/4" plexiglass with 1/2" tempered. If you could go to laminate, then you'd probably get even better, maybe 14 or 15 dB. Theoretically, of course. About the idea of also putting another layer of glass on the neighbor´s window: I'm wondering if that might create a four-leaf system? With only five feet of air space separating your window from his, and considering the sound levels that we are talking about, I'm wondering if that might already be 3-leaf system that you are about to turn into a four leaf system, which would probably be even WORSE isolation at very low frequencies? Maybe I'm barking up the wrong tree here, but to my limited understanding, it does seem like a possibility. Maybe you should ask the acoustic experts here to figure out if this really is a 3-leaf that you are about to make into a 4 leaf. In that case, perhaps a better solution would be to replace his existing window glass with 1/2" tempered (or laminate) glass? Even if it is already 3 leaf, that would still add another bunch of mass, which should gain yo another few dB. One more question: Are you sure that it is only the WINDOW that is the problem? Could it be that there is another issue too? I also agree with Brien that maybe drapes, shutters or a plug would be another way of adding just a little more to the total. After all, if you can't do one big step that adds 20 dB of isolation, maybe you can do 20 small steps that add one dB each! Just thinking out loud here. - Stuart -

Well, this is all good advice as usual, thanks! I don't think we have to worry too much about a fourth leaf effect. There's not too much real low end coming through now and the mass of a storm window is not significant in relation. It would just help with the sealing on his side of the issue. The plan of the moment now is going with 1/2 or perhaps 3/8" plate glass (maybe tempered if required by code) on the outside placed in neoprene gaskets all around. If we need more, we can add another 3/8 pane on the inside for serious STC. I know that makes for a three leaf system in my wall but the added mass will outweigh that effect. The idea of a plug could come into play as well later on. This would have to be the biggest plug ever made!!! We were thinking of hanging it on barn door sliding rail to move it in and out. Won't that be fun? OK, glass contractor and building inspector on the way. Oh the joy of owning a recording studio!!!!! -ashley

The plan of the moment now is going with 1/2 or perhaps 3/8" plate glass (maybe tempered if required by code) on the outside placed in neoprene gaskets all around.

Sounds like a good plan!

The idea of a plug could come into play as well later on. This would have to be the biggest plug ever made!!! We were thinking of hanging it on barn door sliding rail to move it in and out. Won't that be fun?

Time for an image upgrade! New name: "Ashely's Stained Glass Cathedral Barn Studio". :)

Oh the joy of owning a recording studio!!!!!

Yeah, but you do have to admit that it ain't boring! :) - Stuart -