Construction Diary - Stockholm/Sweden

open back should be closer to the wall - say 400mm

Thank you Glenn! I will go with the open back then. :mrgreen: Going to fight the router right now :wink: Sincerely, Useg Diaz-Granados

Routing today went ALOT better (lol) :lol: although I only got one piece done. I've made a sketch of the sound cloud Glenn. Dimensions are 1450 mm x 1490 mm. Q) Do you think there is room for improvement Glenn? By the way, I have not added the led lights to the sketch, they will be placed in the middle of the cloud. Sincerely, Useg Diaz-Granados

consider a good angle on the cloud - say 22.5 - 30 degrees low in front

Thank you Glenn! I have some concerns about the length of the cloud. Q1) Currently, the cloud covers me over the mixing position but not my computer. Do you believe I need a longer cloud in order to achieve my main objective (accurate translation of mixes) Glenn? I made a more detailed sketch in order to illustrate my point. Q2) At a 22.5 degree angled sound cloud there is only 1560 mm of space from the front of the sound cloud to the floor :shock: :shock: :shock: :shock: :shock: :shock:!!!!!! I know I am short Glenn , but I think that makes the room a little to "claustrophobic" for anyone who will enter it. If angled at 12.5 degrees the distance in between the sound clouds front to the floor increases to 1807.1 mm. I made the cloud larger compared to the sketches shown below; 1800 mm long + 1450 mm wide. Can you angle the cloud less or would that defeat the purpose Glenn? Q3) I know we covered some of this already BUT (lol) can you make an open sound cloud like the bass traps with no back; if it is required to have a sealed/caulked back; what is the minimum thickness of the MDF used :?: :?: :?: :?: :?: :?: Q4) Is it OK to route the side frame (i am not referring to the sealed/caulked MDF) like I am doing my broad band absorbers? By the way, I did not angle the sound cloud on the sketches shown below :wink: . Sincerely, Useg Diaz-Granados

Perhaps a sawtooth cloud. If a series of smaller panels is now out of the question, perhaps create a sawtooth back on the cloud. This would reduce the impact on overall height.

exactly - a series of smaller clouds slightly overlapped to get down in front and up in back so you have the head room but also the waveguide action and absorption.

Thank you BriHAR & Glenn. :D Your recommendation raises a few questions in my mind. I have to keep the total weight of the cloud(s) under 20 KG; that is the current threshold of the ceiling. I reduced the weight of the broad band absorbers wooden frame substantially by "routing out" two 20mm channels. I could apply the same method to the clouds wood frame if it is applicable. Q1) Can either one of you be kind and post a link of this sort of saw cloud in order to facilitate the design process (sketchup etc.)? I will go though the forums search function; but sometimes that process yeilds limited results. Q2) Glenn, can you be so kind and explain how the cloud should be assembled? Should the cloud be sealed or opened? If closed should it be caulked? Are the clouds like the bass traps where different construction methods might be applied, if this is the case, can you give me an indication of what the variables might be? Q3) How many of this "saw clouds" do you guys believe are needed for me to meet my main objection with this project (accurate mixes that translate well)? If possible I wish to keep the number of sound clouds low because of the ceiling weight issues. http://www.johnlsayers.com/phpBB2/viewtopic.php?f=3&t=2916&hilit=make+cloud An update; I am getting close to the completion of the routing of the broad band absorbers, made some miss calculations and have to buy more wood. I have to cut/router two (2) final pieces before varnishing and assembly begins. Sincerely, Useg Diaz-Granados

check in JohnH's design thread where I posted a detailed cloud design file which has the clouds with routed panels and cloth absorber faces. in your model you would turn it side ways and repeat (2 or 3) units to achieve the desired angles and absorption. in your case due to weight, use a single layer of plywood and perhaps metal corner bead on the absorber edges.

Glenn, I've looked at that sketch, that is A LOT (lol) of clouds, I am trying to limit them to two maybe three clouds tops. I know that you do an excellent job and are constantly having a dialog with a large amount of people; but in this case I don't think or feel that I got answers to the questions I asked. Q1) Is it possible to have an "open cloud", after all the clouds on the johnH sketch are open since (as I understand it with my limited knowledge in this field) the plywood/MDF is routed. Q2) I have seen some of your other saw cloud designs that you posted in this forum Glenn my assumption is that the clouds might be constructed in different ways like the bass traps. Is this a logical assertion Glenn :?: :?: :?: :?: :?: :?: It would not hurt if you are kind enough and post some links of your sketches, I would be more then thankful to avoid the numerous hours spent on searching; I rather spend that time constructing in order to move forward with the project. Q3) What is the minimum thickness of MDF (this is ONLY if it is a mandatory requirement for me achieving my main objective with this project). :mrgreen: :mrgreen: :mrgreen: :mrgreen: :mrgreen: :mrgreen: Simple, concise answeres directly connected and related to the questions I ask would be highly appreciated :wink: Sincerely, Useg Diaz-Granados

My second suggestion was for a larger cloud, to create a sawtooth at the back of the frame so the plywood or mdf backing would be in smaller angled sections. I have to admit I've never seen it done, but it should work similarly to a number of panels hung in sawtooth fashion. The large cloud would hang flat the sawtoothed backing would create the wanted angled reflection much the same as if the entire panel were angled / or a set of smaller angled panels were used.

Brian, I am having a hard time visualizing it. Would it work? I am thankful for your engagement and hope you understand that at this stage of the project I want to minimize the experimentation process and pursue what has been proven to work. Sincerely, Useg Diaz-Granados

Some of the answers I have asked concerning the cloud have been right in front of my nose. I post the links again in order to facilitate the process for others in this forum. http://www.johnlsayers.com/phpBB2/viewtopic.php?f=3&t=11107&p=79296&hilit=cloud#p79296 http://www.johnlsayers.com/phpBB2/viewtopic.php?f=3&t=13154&p=90449&hilit=cloud#p90449 http://www.johnlsayers.com/phpBB2/viewtopic.php?f=1&t=14736&p=109669&hilit=Glenn+cloud#p109669 http://www.johnlsayers.com/phpBB2/viewtopic.php?f=3&t=14988&p=106972&hilit=several+clouds#p106972 http://www.johnlsayers.com/phpBB2/viewtopic.php?f=1&t=1569&hilit=cloud http://www.johnlsayers.com/phpBB2/viewtopic.php?f=1&t=15423&hilit=cloud&start=60 http://www.johnlsayers.com/phpBB2/viewtopic.php?f=1&t=16098&p=114061&hilit=cloud#p114061 http://www.johnlsayers.com/phpBB2/viewtopic.php?f=1&t=15855&p=113010&hilit=cloud#p113010 http://www.johnlsayers.com/phpBB2/viewtopic.php?f=3&t=14177&p=99258&hilit=hard+cloud#p99258 http://www.johnlsayers.com/phpBB2/viewtopic.php?f=3&t=10427&p=75095&hilit=plywood+thickness+cloud#p75095 On the last post; Eric Desart can't be human, that's what I call dedication to what you engage yourself into understanding and mastering! Even though these posts answer some of the questions I asked I would like to understand the cloud construction process much better. Q) Glenn in one of your posts you mentioned that a hard back sound cloud solve problems around 200 Hz, in an other post John Sayer himself stated (as I understand it) that an open cloud is better at normalizing low frequencies and that angling the cloud would be a sufficient remedy in order to combat flutter echoes (hard top cloud). What is not clear to me is A) Does the hard top cloud have to be sealed like the saws? B) The MDF, plywood thicknesses do you use both and how thick do they have to be? C) Is the hard top generally better then an open cloud because of how it handles mid range frequencies? I need a clearer understanding in order to make an informed decision not made on false presumptions or assumptions Glenn. That is why I, once again ask you to clarify the variables connected to the questions I asked :D Sincerely, Useg Diaz-Granados

the hard back helps break up the modes - angling also provides a more broadband effect than simply making it flat. it acts as a wave guide too so absorption over the back of the cloud helps with trapping. the hard back itself isn't specifically to address something higher up like 200hz - the 100mm porous absorber should handle 200hz reasonably well. it's the 100hz and lower that you need to shift and absorb - a massive panel cloud helps much like you would use hanging broadband absorbers in terms of interfering with the pressure gradients. think of it as making the resonances in the room work harder and therefore you have an energy transformation via absorption...

Thank you Glenn! Q1) Glenn, with the massive cloud, how thick should the plywood/MDF be (thinking about the weight), does it have to be caulked? Q2) I am thinking of making two (2) cloud with a combined total length of 1800 mm. Which cloud should be larger? Should the two clouds be the same length? I want to purchase the wood needed to make the cloud tomorrow, your answer/guidance would make my intention possible. :D :twisted: :twisted: :twisted: :twisted: :twisted: :twisted: Based on the Eric Desart link i feel confident enough to buy the wood for the cloud. I will make two (2) clouds, my first (1st) clout will be angled 30 degrees and will be 1450 mm wide, 720 mm long. It will contain 80mm sound treatment insulation and will be housed in a wood frame that is 95mm thick. This cloud will also contain 3 led lights (with a corresponding dimmer that is already installed and working). The second (2nd) cloud will be angled at 12.5 degrees, will be 1450 mm wide and 1080 mm long and contain the same sound treatment insulation and wood frame as the first (1st) cloud. Both clouds will have a 16mm routed (to keep the weight down) MDF back panel; here I will use the JohnH example hoping that the routing will get down the weight factor to an acceptable level. Here are some pics. Sincerely, Useg Diaz-Granados

looks good!

Thank you Glenn! The sketch could not have been conceived without your assistance. :D Sincerely, Useg Diaz-Granados

Sorry I didn't get back sooner. My concept for a sawtooth Cloud is as in the picture attached. The top side sawtooths are covered with mdf or plywood sheets, and the unit filled with FG as in a normal hardbacked cloud. It provides the modification of the local floor ceiling modes - much the same as using a sawtooth configuration of splayed walls at the side instead of splaying the entire wall - but allows the cloud to hang horizontal while still providing reflection for a RFZ as would an angled cloud..

Looks different BriHar. I am going to go with the two (2) clouds. Have you tested your concept? Hope it works and catches on. :D A quick update; had a fight with the router today......the router won (lost a piece of wood). The wood pieces for the frame of the cloud are cut. Bought the MDF for the clouds. The MDF piece for the little cloud is cut. The big cloud piece was dimensionally to big for the MDF that is available here in Sweden. I cut a piece for the big cloud that was around 230 mm short of how big the cloud should be. I will center the piece that I cut on the wood frame and then place the remaining 115 (x2=230) mm MDF stripes on the side of MDF piece that is already cut and then screw them into the clouds wood frame. Q) Glenn, since there is so little MDF remaining is it even worth placing the remaining 230mm of MDF on the cloud? I could leave the sides without the MDF. Would that be good for bass absorption? Would it cause flutter/mode problems? Sincerely, Useg Diaz-Granados

Useg Diaz-Granados wrote:

A quick update; had a fight with the router today......the router won (lost a piece of wood).

Rather a bit of wood than a bit of anatomy :wink: ... unless of course you're Pinocchio :lol:

:lol: :lol: :lol: :lol: :lol: :lol: BriHar! Could not have articulated it better myself. It went better today. :D I finished routing the pieces for the small cloud. Hope to get the rest of the routing done for the broadband absorbers and the cloud tomorrow. After that is time for sanding and varnishing. Sincerely, Useg Diaz-Granados

Q) Glenn, could you be kind and answer the last question I asked :mrgreen: ? Got a few more questions Glenn related to the JohnH clouds and their routed slot distances. Q1) I noticed that the distance in between the slots on the JohnH vary depending on the size of the cloud. My cloud dimensions differ when compared to the JohnH clouds. Is their any formula I can use in order to calculate the slot distances accurately? Q2) I did not want to compromise the cloud(s) weight limit since I have to adhere to my ceilings weight threshold; so I had no choice but to go with the 12 mm MDF instead of 16 mm. How will the reduction of the MDF's density ( I presume that it will) affect the two (2) clouds overall efficiency? Q3) Made a sketch of the hangers that will hang under the flush mounts wood frame. What should the minimum be of the string that the hangers hang from be (before the insulation start that is)? I have a 200mm gap for the air intake, is that enough Glenn? Finished routing the two (2) clouds. 2 pieces remain to complete the broadband absorbers. :D More sanding has to be done before I start varnishing the wood. Here are some pics of the routed wood pieces, the dimmer (put it up to test before placing drywall) and the holder for the star lights. Got the right star lights this time, trying to arrange a date with the electrician in order to completing the electric work. Sincerely, Useg Diaz-Granados

the slots are just positions on a QRD p=7 pattern. not really critical. the 12mm is lighter and may not provide as much shift but best guess is test and see. 300mm would be better but 200mm should work. LF like wider openings. if you go with 300mm is that a problem?

Thank you Glenn! :D 300 mm should not be a problem as far as the air intake for the flush mount stands. I used the search function in order to comprehend what you mean with a QRD 7 pattern without understanding anything :oops: . Could you be so kind and explain to me how the QRD pattern works? I need some insight into what you think about the hanger sketch (minimum length of cord etc) and on the question concerning leaving a total of 230mm on the sides of the large cloud without any MDF (only insulation) Glenn. Q) I recalling seeing some of your hanger sketches Glenn where the hangers hang right behind the audio monitors (near fields). Is their any particular way of approaching hanging the hangers behind the monitors (outside of making top and bottom ports on the flush mounts) in order to ensure that a proper amount of air cools down the monitors? An update; we tried to install the star lights a second time AND THEY WORK!!!!!! :yahoo: :yahoo: :yahoo: :yahoo: :yahoo: :yahoo: Here are some pics of the star light dimmer and the corresponding lights (they are place towards the back of the studio on each of the two (2) walls). Sincerely, Useg Diaz-Granados

I been waiting patiently without getting a reply from you Glenn :shock: :shock: :shock: :shock: :shock: :shock: :horse: Vacation maybe?????? :mrgreen: :mrgreen: :mrgreen: :mrgreen: :mrgreen: :mrgreen: Anyway I need yet another question answered that concerns caulking. According to the information I received in this forum caulking should be done where drywall touches the floor, the ceiling or another wall. The guy in this youtube clip uses another approach, he caulks even the areas where the different sheets of drywall meet? http://www.youtube.com/watch?v=Wf6ExtPR9Xs I would loooovvveee to hear what the honorable members in this forum viewpoints are in order to determine if this guys approach (the youtube clip) is over kill or not; (Glenn maybe :?: ). An update; hope to buy drywall tomorrow, the electricity is done, the cloud pieces are sanded (and looking MUCH BETTER lol) but are not varnished yet. Finishing up some prep work so we can start putting up the dry wall (with all the delays it feels like it will NEVER (lol) happen. :wink: I'll post some pictures soon :shock:. Glenn, I need you my brotha! Sincerely, Useg Diaz-Granados