John Sayers' Design Forum

John Sayers' Recording Studio Design Forum

A World of Experience
Click Here for Information on John's Services
It is currently Thu Aug 06, 2020 4:35 pm

All times are UTC + 10 hours




Post new topic Reply to topic  [ 1542 posts ]  Go to page Previous  1 ... 89, 90, 91, 92, 93, 94, 95 ... 103  Next
Author Message
 Post subject:
PostPosted: Tue Sep 11, 2007 12:56 am 
Offline
Moderator
User avatar

Joined: Mon Jan 03, 2005 4:08 pm
Posts: 4280
Location: Sacramento, Northern California, USA
I'd like to make sure the goal of the silencers is clear: to maximize transmission loss (TL). I don't care very much about a little noise from the air movement through the registers.

I'm surprised that just having a large empty box lined with the JM duct liner is sufficient to do that. I thought I'd need to have fairly thick absorbtion material inside the box. I had been wondering if 6" (more like 5¼") of mineral wool across the top of the box would be sufficient -- and now it seems I'll going in the opposite direction -- less absorbtion, more open space... :?

Granted, the duct liner acts as an absorber -- I'm just surprised that the absorbtion properties of the liner is better than thick mineral wool.

Rod, you mentioned lab reports -- where might I find those? I'd like to study this more.

I'm surprised this hasn't come up on this forum before... :?

--Keith :mrgreen:

_________________
"Converting a garage into living space requires a city permit . . . homeowners insurance won't cover a structure that's been changed without a building permit . . ." --Sacramento Bee, May 27, 2006


Report this post
Top
 Profile  
 
 Post subject:
PostPosted: Tue Sep 11, 2007 12:48 pm 
Offline
Senior Member

Joined: Wed Oct 08, 2003 1:48 am
Posts: 1464
Location: Central Village CT
sharward wrote:
I'd like to make sure the goal of the silencers is clear: to maximize transmission loss (TL). I don't care very much about a little noise from the air movement through the registers.

I'm surprised that just having a large empty box lined with the JM duct liner is sufficient to do that. I thought I'd need to have fairly thick absorbtion material inside the box. I had been wondering if 6" (more like 5¼") of mineral wool across the top of the box would be sufficient -- and now it seems I'll going in the opposite direction -- less absorbtion, more open space... :?

Granted, the duct liner acts as an absorber -- I'm just surprised that the absorbtion properties of the liner is better than thick mineral wool.

Rod, you mentioned lab reports -- where might I find those? I'd like to study this more.

I'm surprised this hasn't come up on this forum before... :?



Keith,

you're talking apples and oranges here..........


if outside noise getting into the room via the duct is an issue - then first you build a box based on the MAM system - and INSIDE of the stud cavity you use regular fluffy insulation (unless rockwool is just so much cheaper) because rockwool doesn't really add much if anything to the isolation equation.

But - once you are done that - you have to deal with sounds traveling through the duct itself - and THAT is what the baffle system inside the box is dealing with - that and that alone.........

The treatments you add inside your room don't do a whole lot for isolation from the outside world - they only help to attenuate that which exists within the room itself - the same goes for the box.

Just go to the namufacturer's sites - they all list the test results for each of their materials........

For example- linacoustic:

http://www.jm.com/insulation/performanc ... tic_rc.pdf

Rod

_________________
Ignore the man behind the curtain........


Report this post
Top
 Profile  
 
 Post subject:
PostPosted: Sat Sep 22, 2007 7:11 am 
Offline
Moderator
User avatar

Joined: Mon Jan 03, 2005 4:08 pm
Posts: 4280
Location: Sacramento, Northern California, USA
Thanks for the clarification, Rod. I think I'm getting this.

I do understand (and have understood for some time now, thankfully :-)) the fundamentals of Mass-Air-Mass, where the amount of mass in the leaves, their resonance frequencies, dampening that resonance (perhaps with the help of constrained layer dampening, such as Green Glue), and the depth of the air gap, all come into play.

What I didn't (and may not still? ;-)) understand was how silencers are supposed to work.

What I'm now hearing from you is that using a duct liner product, such as Johns Manville Permacote® Linacoustic® R-300 Rigid Fiber Glass Plenum Liner Board, or a competing product I discovered, Knauf Rigid Plenum Liner, is advised, and (this is key) the more lined surface area the air is exposed to, the better the silencer will perform.

Do I have that right?

If so, the surface area inside the silencer will be around 6" x 10½" x 32". I need to be sure this is a sufficient volume of surface area that will work for my needs. If it is not, I can afford the space to have the silencer drop down into the room, thus increasing that 6" height to 12" or perhaps taller if needed. I'd rather not, as I think the room will look better with a flat ceiling, plus the drywall and finishing will be easier to complete if it's flat... But I'm willing to do it if it is necessary.

I'm currently waiting on a callback from [url=http://www.a-m-s[/url]Acoustical Material Services[/url] (their Sacramento area location is now 3.3 miles from my house :twisted:). They don't stock those products but they think they can order some for me.

--Keith :mrgreen:

_________________
"Converting a garage into living space requires a city permit . . . homeowners insurance won't cover a structure that's been changed without a building permit . . ." --Sacramento Bee, May 27, 2006


Report this post
Top
 Profile  
 
 Post subject:
PostPosted: Sat Sep 22, 2007 11:12 am 
Offline
Moderator
User avatar

Joined: Mon Jan 03, 2005 4:08 pm
Posts: 4280
Location: Sacramento, Northern California, USA
Phooey... I haven't heard back from AMS or the other place I called... :evil:

_________________
"Converting a garage into living space requires a city permit . . . homeowners insurance won't cover a structure that's been changed without a building permit . . ." --Sacramento Bee, May 27, 2006


Report this post
Top
 Profile  
 
 Post subject:
PostPosted: Sat Sep 22, 2007 11:59 am 
Offline
Senior Member

Joined: Wed Oct 08, 2003 1:48 am
Posts: 1464
Location: Central Village CT
Keith,

basically you want the free area (volume) inside the box to be double that of the supply to the box itelf........

Rod

_________________
Ignore the man behind the curtain........


Report this post
Top
 Profile  
 
 Post subject:
PostPosted: Tue Oct 02, 2007 1:42 am 
Offline
Moderator
User avatar

Joined: Mon Jan 03, 2005 4:08 pm
Posts: 4280
Location: Sacramento, Northern California, USA
I finally heard back from one place, saying they can't get their hands on Johns Manville Permacote® Linacoustic® R-300 Rigid Fiber Glass Plenum Liner Board. The other place hasn't called me back yet and I'm not confident.

Ends up that I just discovered while surfing around the Johns Manville Web site that Permacote® Linacoustic® is discontinued, being replaced by Linacoustic RC™. Excerpt: "If you have a job with Permacote Linacoustic specified, don’t worry. Linacoustic RC is the perfect replacement. It’s virtually interchangeable with Permacote Linacoustic and, in some instances, actually superior."

So it looks as though I'll be restarting my search for a local(ish) supplier of Linacoustic RC™ - Fiber Glass Duct Liner With Reinforced Coating System -- indeed, the exact "example" product that Rod told me to look at in the first place! :roll:

--Keith :mrgreen:

_________________
"Converting a garage into living space requires a city permit . . . homeowners insurance won't cover a structure that's been changed without a building permit . . ." --Sacramento Bee, May 27, 2006


Report this post
Top
 Profile  
 
 Post subject:
PostPosted: Sat Nov 24, 2007 10:56 pm 
Offline

Joined: Mon Aug 21, 2006 3:43 am
Posts: 185
Location: south london uk
hello mate hope all is well.

have you got any further with your silencers and fresh air system?


Report this post
Top
 Profile  
 
 Post subject:
PostPosted: Sun Nov 25, 2007 7:10 am 
Offline
Moderator
User avatar

Joined: Mon Jan 03, 2005 4:08 pm
Posts: 4280
Location: Sacramento, Northern California, USA
Hey everyone,

I've been so busy with work and distracted by other family-related things lately. Plus I've taken up tennis again and that's taking up some of my weekend morning time lately. Good exercise and lots of fun with the folks I've met playing here.

I haven't touched anything in my room for about two months. I realize I'm heading right into the holiday season, but I'm going to really try to turn it back on in December and January.

I can't believe I'm not done yet. I started this thread in January of 2005!

Hopefully I can steal an hour or so during the week to figure out where the heck I can get a small quantity of good quality duct liner.

Sorry I've been so absent here.

--Keith :mrgreen:

_________________
"Converting a garage into living space requires a city permit . . . homeowners insurance won't cover a structure that's been changed without a building permit . . ." --Sacramento Bee, May 27, 2006


Report this post
Top
 Profile  
 
 Post subject:
PostPosted: Mon Nov 26, 2007 5:13 pm 
Offline
Senior Member
User avatar

Joined: Sat Mar 29, 2003 12:26 am
Posts: 2073
Location: Netherlands
Hey Keith,

I had just entered another message in your "Not dead dead..." thread haha!

Good 2 c u alive buddy. Now, quick tennis, give up on those extra timespending jobs and start cracking man. Build that studio!

haha, no serious. We SHOULD have a live out there.


Report this post
Top
 Profile  
 
 Post subject:
PostPosted: Wed Dec 26, 2007 12:56 am 
Offline
Senior Member
User avatar

Joined: Wed Aug 10, 2005 8:02 am
Posts: 657
Location: Big Spring, TX, USA
Merry Christmas (again) Keith!

Perhaps your "layoff" on the studio work might be to your advantage. Remember the V cutting tool and PE "rope" (for sealing drywall joints) that I promised you a while back? Well, I still have them sitting a box to send you if your still interested.

As to your duct board sourcing problem, I used an OC product (oddly enough called "Duct Board" that, at least until a couple of months ago) was readily available at my local supplier. The only stuff he had in stock we 1" thick and foil backed but I believe it's also available in 1 1/2" and 2". If you can find my thread, near the end of it, you can see the little "elbows" I made from the stuff for my send/return vents in the control room.

It comes is 4' x 10' lengths and the last time I priced it, it was about $45/sheet (in W. Texas). When I got my original order, it was about $36/sheet so who knows how much it goes for today.

My plenums were made from just the duct board (i.e., no plywood outer shell) and work just great! Of course, they are 24" x 24" by almost 30' long (one each for send and return air). If fact the only "problems" I ended up with in the HVAC system were:

1) The loudest sound in the big room is when the relay in the themostat clicks on and off and...
2) I neglected to see if my natural gas line in the building was actually connected to something outside the building. When they came to pressure check it before putting on a meter, it turns out you can pretty much just blow into the pipe. The gas company figures that the pipe collapsed somewhere under ground (on my side of the meter) and that more than likely, when the dentist built his office next to the studio (between me and the meter), it was built directly over my gas line (and was probably severed or capped off) in the process! Since it's illegal (in Texas any way) to build a structure over a functional gas line, they took the easy way out and made it non-functional. I <i>could</i> petition the city to have his building torn down but that would not help much with neighborly relations.

The good side of this is that the rooms are so well insulated, a couple of small oil filled electric heaters I got from Walmart warm the place up from 55 degrees or so to a toasty 72 in 30 minutes or so and then they stay at that temp for a long time.

Anyway, again, a Merry Christmas to you and your family. Sorry, no virtual turkeys this year! :-)

len


Report this post
Top
 Profile  
 
 Post subject:
PostPosted: Thu Jan 03, 2008 4:34 pm 
Offline
Senior Member
User avatar

Joined: Sat Mar 26, 2005 8:07 am
Posts: 601
Location: Bay Area, California
happy new year keith! just checking in to see if you had finished yet! i was thinking i would see a completed project and you jammin away and be jealous. so anyway hurry up and get going all right? ok i've had a few beers so don't mind my ramblin. bye now.


Report this post
Top
 Profile  
 
 Post subject:
PostPosted: Fri Jan 04, 2008 12:00 am 
Offline

Joined: Tue Jun 26, 2007 2:08 am
Posts: 220
Location: Newark, DE
Alright Keith, back to the studio- I don't want to finish mine first! You're my inspiration!


Report this post
Top
 Profile  
 
 Post subject:
PostPosted: Sat Jan 05, 2008 2:40 pm 
Offline
Senior Member
User avatar

Joined: Mon Aug 02, 2004 11:23 pm
Posts: 325
Location: Easton, Pennsylvania, USA
I really don't want to go through 90-something pages, but what happened to this guy's build? I've never seen so many pages and crazy-detail as Keith's build. Why has production stopped?

_________________
____________________________________

- Brad

www.theSecretSystemBand.com

"...over the years, 'the-blues' has raised many children..."


Report this post
Top
 Profile  
 
 Post subject: Get Ready!
PostPosted: Tue Jan 15, 2008 12:50 pm 
Offline
Moderator
User avatar

Joined: Mon Jan 03, 2005 4:08 pm
Posts: 4280
Location: Sacramento, Northern California, USA
I just got approved for a whole week off next week, during which I hope to accomplish a lot on the room. I'll be ordering my HRV tonight or tomorrow (yikes, it's expensive!). I'm cutting it dangerously close to my building permit expiration date (again) and need to get the ventilation piece done so that they can sign off on it, which will extend my expiration date again. Not that I want to keep dragging this thing out!

In other news, believe it or not, I may be stacking even more upon my already busy plate. Tomorrow I'll be auditioning to play in a cover band. I'm pretty excited about it but I also know that it would be a time commitment. Fortunately their schedule isn't too hectic (usually one rehearsal every two weeks, plus no more than two gigs per month). A good friend of mine is in the band and the opportunity arose, so I'm going to go for it.

While in theory there will be time away from the build, I'm hoping it will help motivate me because it's been a long time since I've played and it will remind me why the heck I'm building this damned thing!

Look forward to seeing a lot of pictures and not a whole lot of turning back.

Sorry I've been so absent and totally eyes-off around here. Not quite the moderator role model, huh? :oops:

--Keith :mrgreen:

_________________
"Converting a garage into living space requires a city permit . . . homeowners insurance won't cover a structure that's been changed without a building permit . . ." --Sacramento Bee, May 27, 2006


Report this post
Top
 Profile  
 
 Post subject:
PostPosted: Tue Jan 22, 2008 3:41 pm 
Offline
Moderator
User avatar

Joined: Mon Jan 03, 2005 4:08 pm
Posts: 4280
Location: Sacramento, Northern California, USA
Today didn't start well. This morning I called the company from which I ordered my HRV system to check on the status of the delivery. It ends up that it hadn't shipped yet and was not expected to ship anytime soon due to a backorder at Fantech! :evil:

I drove to a local HVAC wholesaler to check on availability there. I learned they don't stock them either and it would take two to four weeks, depending on manufacturer. DAMN. If I had known that buying HRVs required that much lead time, I would have bought one a long time ago and had it waiting for me when I was ready to work on it! :roll:

I called Fantech directly and learned that there's one in their Reno (Nevada) warehouse, but it was already set aside for another order, and that three more were heading to Reno on a truck with an arrival date of Thursday. A little sweet-talking on my part resulted in their giving me the one in Reno and earmarking one of the three for the other order.

I want my hands on this thing very badly, so tomorrow morning I'm heading to Reno to pick it up!

Image

I've been to Reno before -- depending on the time of year, it can be an easy and beautiful drive along Interstate 80 through the Sierras, or it can be a wintery, snowy, difficult and/or dangerous drive.

Guess which way it is this week? :(
    CHAINS ARE REQUIRED ON ALL VEHICLES EXCEPT 4-WHEEL-DRIVE VEHICLES WITH SNOW TIRES ON ALL 4 WHEELS FROM KINGVALE (PLACER CO) TO TRUCKEE (NEVADA CO) . . .

    SNOW IS EXPECTED TO POSE AN INCONVENIENCE TO TRAVELERS. ROADS WILL BE SLICK AND HAZARDOUS...WITH SNOW AND ICE DEVELOPING ON BRIDGES AND OVERPASSES. MOTORISTS SHOULD SLOW DOWN AND USE CAUTION.
I bought snow cables for my tires and new windshield wiper blades. Tomorrow morning I'm heading up the mountain on my HRV quest.

...Provided they don't close I-80! :roll:

_________________
"Converting a garage into living space requires a city permit . . . homeowners insurance won't cover a structure that's been changed without a building permit . . ." --Sacramento Bee, May 27, 2006


Report this post
Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 1542 posts ]  Go to page Previous  1 ... 89, 90, 91, 92, 93, 94, 95 ... 103  Next

All times are UTC + 10 hours


Who is online

Users browsing this forum: No registered users and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group