Green Glue - Page 2

Ted et all,

I fear that it was my comments, in a previous post, could lead someone to the conclusion that the GG is more than the RSIC / Hat channel.



To be clear the original DE design was to use the RSIC clips and channel on one full wall (adjoining the rest of the basement) and half of the ceiling. Half of the ceiling is built below the above floor joists for added interest and to clean up the lines. The other half of the room is at its full 9' height and needed the clips and channel. The rest of the room was built as near to "room with in a room" as I could get.

So, the Green Glue being much more expensive is based on the fact that I can even more effectively treat my ENTIRE room (all four walls, Ceiling, Riser, Stage) with GG rather than using the clips and channel on 1 wall and 1/2 ceiling. There is a tremendous price difference between he two plans. However there is also a tremendous difference between the performance I will get out of this room with Green Glue treatment through out.

If one was to compare apples to apples the Green Glue is far less expensive. I also have the added benefit of being able to hang my NEC XG852 from wooden joists/blocking rather than doing so from the clips and channel. Dennis assured me that I would be fine (and I believe him) but I like the idea of lag screws into wood!!!!!

Hopefully I clarified what might have lead to some misunderstandings and misconceptions about the pricing.

Thanks for the clarification! By the way, I like that projector! Another CRT guy, way to go!

In my experience, GG and RSIC/Hat channel cost about the same. I'm doing both in my HT because I only have one chance to build it, and I doubt it's ever as quiet as I want and I don't want to think "if only..." for the next 20 years.

I've got about 50% of my second layer of drywall up, and 100% of both layers on the ceiling. I've gained some experience applying the green glue and would like to mention a couple things:

1) I found Ted extremely customer oriented. I had an issue of my own making and he dealt with it above and beyond what I would have expected him to. Highly recommended.

2) The product can be messy to install. It's sticky, gloppy, and gets everywhere. In short, it's glue. A large, green bucket of glue.

3) For this reason I would recommend to any new installers that they:
a) make sure there is nothing in the room they don't mind washing.
b) have lots of rags on hand (the shop rags you get at an auto store are great).
c) have lots of patience.

4) Based on my experience I strongly recommend the following specific techniques:
a) For ceiling application, apply the GG to the drywall panels on the ground and then lift them into place. Troweling this stuff on the ceiling is NOT fun and leads to very messy hair. Need I say more.
b) Applying the material to the panels is easiest with a large heavy brush. The one I'm using is about 8 inches wide and very coarse - it's more like a heavy plaster brush than a paint brush. Trying to trowel it on directly or with a spatula like drywall compound has led to lots of glops all over the floor and arms/legs in my experience. Maybe others have more skill than I do, but applying it with the brush and then going over it with the notched trowel has been far (far!) easier in my experience.

I have found it takes me about 10-15 minutes to apply the GG to each 8' x 54" section of wall space, and then another few minutes to shim the drywall in place and screw it in.

I can't speak to performance yet, as mine has not cured and I don't even have a door on my HT yet, but given the data at the website, and Dennis' recommendations, I'm happy thus far with the money spent, though it was a fairly large chunk of change. However you only get a chance to do the room once, you can always buy a more expensive projector later on....

I thought your were going 'punk' with the green hair. Or maybe getting ready for Halloween.

Great thread, starting to get a better understanding of GG.

I'm still in the planning stage, I'm mostly done w/ studding out the walls, but with electrical work, my work and schedule coming up, drywall may be more than a month away. Prior to the mention of GG, my plan was to use RSIC clips on all walls & ceiling, hat channel & 2 layers of drywall.

But this thread has me wondering - is GG & RSIC an overkill? Dennis told Justin in this thread to use Green Glue - are you saying forget RSIC? If that's the case, great, cost & space savings are always appreciated. If that is what you are saying, Dennis, it's saying a lot, as you are a supplier (to many of us here) of RSIC clips - this will be eating a bit into your pocket.

However, I'm with PAP - this is a one time build so having a sense of the relative benefits of one or the other as opposed to both would be useful.

Just what I needed, more things to keep me up at night to decide.

I hope this is not taken in any negative way but... I would like this cleared up, is Dennis affiliated with Audio Alloy in any way? His endorsement of GG is quite impressive and I know Dennis sells/sold the RSCI clips as well.


Craig

Hi Craig,

While Dennis isn't part of Audio Alloy, he was an early adopter and resource for us. I guess he's been around the product longer than most here.

Ted,

A suggestion... have you thought of offering a small sample (maybe a quart for $20?) of the GG to allow any one of us to duplicate the DE demo and to get a feel for working with GG? I would certainly be interested in obtaining a quart of the material before ordering 15-20 gallons of something I have no experience with.

I have no affiliation with Audio Alloy...just the good fortune of working with it early on in its development. I am not, by the way, a distributor for the product. I believe it is sold only directly from Audio Alloy.

I also do not own any stock in the company which I sense will be my own misfortune.

--- I'd like to add the following to this:
I'd don't get paid, nor would I accept a fee for a product "endorsement". I'm not in the endorsement business. For a product to fall into our "approved" list (which means we'll use, or specify, the product in our own work..or my own home):
1. The product must perform exactly as stated, or better than stated;
2. Any claims must be backed by appropriate testing where applicable;
3. The company must provide exemplary customer service;
4. The product had better work the first time everytime;
5. The product (or service) must be of very high quality and of consistent quality.
6. The company's marketing does not mislead, overstate, misinform or "imply";

Examples are SVSubwoofers, Lutron (ISO 9000 and 6Sigma), Stewart Filmscreen, Audio Alloy, PAC-International, among others.

Let me put it into my perspective as a flight instructor ... if I'd let you fly my family, you'll get the signoff/endorsement in your logbook. If not, we still have work to do.

Hi Maddog,

I don't know that we'll be sending out "practice quarts" anytime soon, but you never know

It's just troweled on.

After reading all these posts I am wondering if I should include GG in my build. Below is a the current construction detail.

Front and left wall: Concrete block, furred w/2x4 w/ R19 batted, 1/2" GB (existing w/o GB)
Right and back wall: 2x4 w/ 3" Wet Cellulose, RSIC-1, 1/2" GB
Ceiling: 12" Joist filled with dry Cellulose, RSIC-1, 5/8" GB
Seats are 123.4" and 48" deep. (rows of 4's recliners, maybe 3 @ 93")
Rear seats are on a 10" raised platform.
Seats are 3" off the left wall and center to the screen.
Stage is 4" filled with sand.
The gap between the seats and right wall is 23" or so.

Any suggestions would much appreciated....
I included a basic drawing of my HT.
Tkawika

Why wet cellulose on the side walls?

Three reasons:
1st: Its free...
2nd: I was under the impression its a decent sound dampning material.
3rd: Its free again. Installation and material.

Wet Cellulose is blown in wet and then drys to a firm dry cellulose. If you understood that, I apologize in advance.

Yeah, I understand what it is. No apologies needed. Don't get me wrong, free is always good! I've never used this type of product for HT purposes so I can't say for sure. Just my impressions.

However, I think it acts more like styrofoam from an absorbtion standpoint (could be wrong here) due to its lack of transmissiveness (word?). Also, since it dries solid and has no flex to it like the dry stuff or normal batts, it also makes another path for physical transimission of sound from one layer of drywall (inside the room) to the other layer (outside of the room). It will still help damp the cavity resonances so if isolation is not a major concern, it should work OK.

How well or poorly would this product work with only 1 layer of drywall? (ie. Stud -> Green Glue -> 5/8" Drywall)

How does this product compare to the "other guy", QuietGlue?

Andy K.

In looking at that theater, I'm not so concerned about cavity resonance as I am panel resonance.

Andy, there would be some benefit to treating the stud edges only, but any real difference will only come from the majority of the surfaces being a constrained layer with Green.

As far as other types of materials performance, take a look at the data here:
http://audioalloy.com/green_vs_other...ng_systems.htm

Oh, as an aside - I notice the use of cellulose above. How does cellulose compare with something like Roxul Safe n Sound?

Andy K.

cellulose and mineral fiber have both been demonstrated to be superlative sound absorbers, and superior to the fluffy stuff at mid/high frequencies.

at lower frequencies, it's a crap-shoot, so to speak. wall behavior there is dominated by the interplay of mass and resonance for the most part, and it's not realistic to say either one has a definitive advantage relative to the fluffy stuff. some studies have concluded that plain fiberglass batts are preferable to more exotic materials on the low end.

either is a fine choice, as is the same $$$ worth of plain fiberglass.

putting studs and an air cavity in front of a concrete wall can yield considerable resonance problems that reduce performance at lower frequencies. the following are sensible methods to coping with that

1. utilize as deep as humanly possible resilient connections (like flexible steed studs, wood studs with clips, etc.) and insulation.

1a. damp the panels to mitigate that component of the resonant behavior

2. if using wood studs, damp the panels to mitigate the resonance problem AND, again, utilize absorbing material. a variety of panel damping products are available as well as pre-damped engineered panels.

good luck everybody!

Er, I guess I'm confused. Is sheetrock considered "porous"? I thought the idea was to use Green Glue between two pieces of sheetrock, to create a mastic CLD layer.

Also, I would like to "chime in" for support of you selling 1 quart "samples" as well.

Thanks.

Drywall is porous, yes, allowing the Green to dry. (Glue has to dry). The result is a constrained layer system with the Green bonding the two layers together.

Are there any install insrtuctions? How thick to put it on. Special drywall screwing instructions. (That didn't come out right!) Days required to cure/dry, Etc.

Ted, (BTW Great name)

First I want to say this forum rocks.

Would it be better to fore go the RSIC clips and dble up the GB? As you can see in the paint drawing this would help with the isle next to the seats. I read a previous post that Dennis recomended dble GB w/ GG over the RSIC clips or should I do both and have theater for 6 instead of 8?

Ted K

Ted,

RSIC clips are a great product. If you're saying that by using them you have to reduce your seating, I would consider an alternative.

Directions are fairly straightforward. It's a glue that gets troweled on with our supplied trowel. Sandwich the drywall before Green dries. Done.

drywall, greenboard, OSB, plywood, MDF, particleboard... all of these are sufficiently porous to allow the material to dry. dry time varies with the matrial (fast in drywall, slower in MDF, for example), ambient temp, and ambient relative humidity. you can use one porous layer (drywall, wood, etc.) and one non-porous (painted drywall, metal, concrete, etc.) as well.

concrete is probably sufficiently porous to allow it to dry eventually

So, it's a thin enough layer so as to not have to be considered in room demension calcs? If you take my meaning?

I guess what I mean by "reduce seating" is that in a 2 row 4 seat configuration if I use RSIC clips and dble GB then instead of having 23" isle, it would be around 20" or 28" if I only use dble GB and GG. Is 20" enough, ok walked into that one, but is it?

Ted

Or one gallon tubs, if for no other reason than to accomodate those of us that buy two 5-gallon buckets and find out that we came up about a gallon short.

Is the PRIMARY purpose of the damping to contain the sound from the HT from the rest of the house or is it to keep vibrations from causing sound problems within the theater?

Building 12x9x20 ht... one wall solid concrete others 2x4 studs..just realizing that my planned single 5/8 inch sheetrock may be a problem.

The primary purpose is sound isolation, not in room acoustic response of the room.

....a 201J jockey