Construction Diary - Stockholm/Sweden

Thank you Guys! :D

Glenn I noticed that you in your last saw example used a saw made out of MDF. I've been searching for a few hours now and hope to get your assistance in finding a calculator for calculating how to router the MDF panels (gaps of the slot, slat, how thick the router piece needs to be and what frequencies would be affected etc.). I Like this pic: http://www.johnlsayers.com/phpBB2/viewtopic.php?f=1&t=11542&p=101838&hilit=slot#p101838 and hope that it could be used in my rooms saw design. Are there any drawbacks in using MDF versus wood slots? What do you recommend? Sincerely, Useg Diaz-Granados

Check out the Helmholz calculator from John Sayer's Recording Manual http://johnlsayers.com/Recmanual/index.htm Whether you go for wooden slats or routed panels, I think is more a question of aesthetics. You might want to consider though that once you routed the panel, it can't be altered anymore, whereas individual wooden slats can be repositioned if necessary.

Brian thank you for your recommendation, but; I've downloaded the Hemholz calculator a long time ago. My question to Glenn pertains primarily to the router size (used in order to create the gaps) since I presume that the method used for creating the slots differs from the one used when using wood. If anyone can shine some light into this matter I would be thankful :) Sincerely, Useg Diaz-Granados

the router bit size will be whatever you have determined is the size of the slot opening... so if the opening is 5mm, use a 5mm straight bit, 10mm, etc. on larger openings where you might not have the large size bit, simply route it in multiple passes.

Thank you Glenn! Makes sense. And thank you Brian for explaining the plus and minuses of wood verses MDF slots. An update; Purchased the Halogens for the cloud. Waiting for the supplies that I ordered for the electrical work (wire etc.), the dimmers and the star led lights. As soon as the supplies are in I will do the boxes to insure sound isolation for the dimmers, electric boxes etc. Then, (I hope!!!!!!) after the wires are drawn, that we will FINALLY put up the drywall :yahoo: :yahoo: :yahoo: :yahoo: :yahoo: :yahoo: Then I will get a sound analysis of the room (due to the dimensions of the room there are some NASTY nodes to deal with) and use those measures after consulting with you guys to "calibrate" the slots. After that it is time for the flush mounts, saws, cloud, broad band absorbers and light installation. Now I am going back into sketch mode to put some "flesh" on the "bones" on the skeleton of the room. Got inspired by John's last completed room design in Bombay India. Hope ya all aight!!!!!! Sincerely, Useg Diaz-Granados

Made a wood frame for the room (I am talking about a sketch lol :twisted: ). Glenn anything you think needs to be improved. Got a question concerning the MDF placement; can I leave any open gaps that are not visible in the back of the flush mounts or does that defeat the purpose of flush mounting the monitors? I know that the saws have to be caulked properly so that the slots work correctly; if I drill the wood construction to the saws do I caulk in order to avoid damaging the functionality of the slots?????? Sincerely, Useg Diaz-Granados

attaching things to the front of the slats-saws? the air cavity needs to be sealed. the front has openings :D the leading edge of the saws should be absorptive. i'd merge the outside edge of the soffit into the first slats so it's a smooth transition and if you can afford a bit of space in-between the soffits to widen the soffit faces. make sure you measuring includes decoupling the speakers from the surrounding frame and stand.

Thank you Glenn :D , but I was also curious about the connection points of the flush mount wood frame (the frame I added) when they are attached and screwed on to the saws (like in the back pic). Since the saws have to be sealed like you pointed out, is it enough to caulk in order for the saws to be air tight (might sound like a silly question but I want to make sure)? I only got 2070mm to work with as far as the spacing of the flush mount is concerned. Since I presume (please correct me if I am wrong) that the saws require 400mm to work correctly (200mm each) that leaves me with 1670mm to work with, take away an additional 180mm (45mm on each side once the monitors are on the monitor stands) leaves me with 1490mm counting from the far end of the monitors (not centered) in between each monitor. I have to make the sealed 20 mm MDF box that are going to house the monitors (with an open back for cooling the amp in the back) which leaves 25mm (each side of each monitor) for the MDF flush mount plate that will go all the way up to the ceiling. I think I understand what you mean by merging the slot to the edge of the soffit corners, that should not be that difficult to do. :mrgreen: Is there anything I have not looked at? A better way of approaching the spacing issue(s)? I have another question Glenn? What is the easiest way of decoupling the monitors?????? Is it enough with rubber pads, I've looked at a lot of links but can't quite wrap my head around it. :oops: Sincerely, Useg Diaz-Granados

Still would like to have the "how to easiest decouple" the monitors question answered. I know that you pros might think that the question is elementary and that the answer is easily reached by using the search function; regardless of that I want to ensure I DO NOT make a mistake based on a false presumption. I get the sense that (might be a little bit unfair way of looking at the political reality in this forum )some of the pros in here are all to happy to comment something AFTER something already has been build or constructed and they can point out how you screwed up :roll: . I have a few questions that are connected to the pics that got posted (I presume some of you are going to comment on the way the roof has been assembled; IT WILL stay that way; the steel strip that runs along the ceiling is there to insure that the weight of the cloud can be supported, and YES it makes contact with the ceiling above which is not the optimal way of achieving good sound isolation). Q1) One of the picks shows a wooden box that I made out of MDF that is going to contain my dimmers. Once the resilient channels are placed on the studs they add an additional 15mm. The drywall is going to be 30 mm in total. My objective here is to place the box flush with the drywall which would be sticking out 45 mm from the end of the stud. How much can the drywall move once its weight is on the resilient channel?????? Q2) I plan to end the drywall where the resilient channels end and then use caulk on the drywall and the stud. Is that OK?????? Sincerely, Useg Diaz-Granados

Good carpentry and caulk will do the sealing you need on the saws. On the speaker, if you decouple the speaker from the box using agglomerated foam, sorbathane, sylomer, or soft neoprene or a closed cell foam, you can make it just snug enough not to move but not tight enough to directly couple. Leave a slight gap around the speaker face and the soffit plate and seal around the edge with caulk or rubber.

Like always, Thank you Glenn :wink: . As far as the electric box I made for the mix rooms dimmers, will the drywall move considerably when the weight of the drywall hits the resilient channels?????? When you seal the monitors with caulk, what can be done not damage the monitor and how do the stud corners look in terms of caulking once the drywall is up (the pics) :?: Sincerely, Useg Diaz-Granados

Here is some pics on today's progress; the dimmer box in place and the cables that are going to the star pattern led lights. Have not caulked the holes in the box yet. :wink: Now I have to complete the boxes that are going to contain the star led lights. Questions; Q1) Still would like some answers regarding my last post when somebody (Glenn I hope) has a chance. Q2) Would applying a damping compound (density 1040 per square meter; it seems to function like green glue; according to the information i received the compund made out of polyurethane converts the sound waves to heat) possibly be beneficial with regards to reducing the flaking paths of my ceiling? An update on the sloooooow :cry: progress we are making; the electrician will not be able to make it until wednesday. Hope to make some further progress then!!!!!! Sincerely, Useg Diaz-Granados

the resilient channel will shift when weight is applied (RC-2 very little, RC-1 probably 1/4") so if you're working within 5mm tolerances for the drywall all will be good... on the monitor - latex caulk shouldn't impact the speaker as it will peel away pretty easily.

I have not said this before, but you are THE MAN Glenn!!!!!! :twisted: :twisted: :twisted: :twisted: :twisted: :twisted: What do you think about the compound Glenn, translated to US dollars is a few hundred bucks and is suppose to add a reduction of 8 to 16 dB (it is a glue that goes between the 2 layers of drywall)? My thought is to only apply it to the ceiling. Q) I plan to end the drywall where the resilient channels end, there is no connecting drywall, just the stud. (Look at my corner pics) My question is; is it OK just to use caulk in the corners? Won't that cancel out the resilient channels function since the studs that the caulk goes on are connected to the wood frame without being decoupled? Sincerely, Useg Diaz-Granados

the Green Glue or Quiet Glue are constrained damping compounds which can enhance the overall transmission loss of the wall and ceiling assemblies and in the right situation are very useful - but it often comes to a budget to make the call versus simply adding another layer of drywall. on the drywall corners - if you couple the drywall to the frame instead of the isolated hat channel/furring strips, you're short circuiting your investment. the caulk isn't really coupling so if it's only a caulk edge then OK, but if you're screwing/nailing/gluing then that is not good. think of it in terms of a pair of tin cans as a child's telephone:

Thank you for the informative and easily digestible example Glenn. :D Your advice has been of tremendous use throughout my decision making process during the different phases of this project. I have a question Glenn that concerns the broad band absorbers that are going to be next to the saw slots. Q) I plan to fasten the broad band absorbers to the wall with drywall anchors which means that I have to locate all the tree studs before placing the drywall in order to insure no "short circuiting" of the resilient channels. I assume that we have to use sound caulk in order to avoid sound leaks. The problem is that the anchors that I've found only are for walls that are up to 27mm thick and the walls are 30 mm thick (double 15 mm drywall). The anchors are 75mm long and have a 13 mm diameter. http://www.jula.se/gipsankare-365020 Is there a particular way of caulking the anchors once they are in place Glenn? What drywall anchoring method do you recommend? Sincerely, Useg Diaz-Granados

look for "drill point anchors" - basically you drill a start hole and screw them into the drywall then screw your hooks etc into those. the other option is a French cleat which is a batten screwed into the studs and it has an angled cut which matches a block on the absorber - you can move them back and forth as well as easily put up or down as needed. plus more rugged.

Thank you so much Glenn for guiding me in the right direction! :D The electrician will be here tomorrow, so I'll post some pics then. I have a question Glenn. Q) Is it OK to screw in the french cleats on the studs before putting up the drywall (cutting hole in drywall with margin for sound caulk and drywall movement once the drywall is on the resilient channels etc.). Sincerely, Useg Diaz-Granados

the cleats sit inside the room :-)

Sorry Glenn, with inside the room, do you mean the cleats go trough the drywall after the drywall has been fastened to the resilient channels or on the tree studs before the drywall has been placed :oops: ? Sincerely, Useg Diaz-Granados

screw in either anchors or into the resilient channel. it sits on the drywall face.

My apologies Glenn :?, I do not understand/comprehend your recommendations from a cognitive perspective. Glenn Q) Is it a correct presumption that when using cleats they are placed on the drywall studs before the drywall goes on as compared to using the other method you earlier recommended, are attached through the drywall onto the resilient channels? I might be over complicating things but I really do not understand what you are typing. :wink: Sincerely, Useg Diaz-Granados

let's assume you have all the drywall completed. you have a blank room. you would attach the French cleats on the drywall surface - either with drywall anchors or by carefully screw into the resilient channel (or hat channel - assuming you use iso clips). the absorbers then have a corresponding cleat on them which hangs on it.

Thank you Glenn! :D Have a few questions related to your clarification. Q1) Is this the sort of anchor I would need? http://www.youtube.com/watch?v=4bJGfACyssY&feature=list_related&playnext=1&list=SP0E2013E83DAE698D Q2) Any particular drywall anchors you recommend Glenn? Q3) Are they any advantages/disadvantages to drilling the cleats into the resilient channels as compared to the drywall? Q3) When applying sound caulk. Do you "cover up" any eventual holes that are made after the cleats have been attached to the drywall anchors or is it advisable to approach this in a particular way? An update on the projects progress; unfortunately the electrician is in the hospital taking care of one of his family members; My family extends its best wishes and kindest regards to him and his loved ones. Sincerely, Useg Diaz-Granados