SIMO Studio - Construction Phase

Hi Simo, Well, I did get some strange looks from the ladies at 'JoAnns Fabrics' :twisted: Apparently, the 'batten' material is used in a variety of applications. I think my material was the 4oz variety [need to check]. It is very lightweight [can tear easily], but it is both 'airy' AND it provided a type of 'primer' base that helped give an opaqued look for the fabric [made the panel covers and traps less transparent VISUALLY. I debated whether to add the plastic sheets to start. But with the design I ended up with on the 4 corner traps, my frames can be pulled out and I could then add a plastic sheet. To be honest ... the room just does not seem to need it. [at this point]. Currently, I'm doing very minor things to the room. Mainly I've been tackling several audio projects, and testing how things transfer to the outside world. The biggest obstacle is my old, huge CRT monitor. I still looking [and saving up pennies] to replace this beast. Looking flatscreen around 24"+, with the right screen rez for running DAW's [I don't watch video too often]. Once bought, I can finalize my design for my desk size [all the parts are in the other room]. The OTHER factor is ... after being out of the studio for several years, I'm enjoying working in this room. Everyone that's been in is nothing but positive. This Studio design forum is a godsend. That's why I try to read the postings most everyday, and occasionally, stick my foot in the door if I see something that I can spur an idea, or relate my experience ... and also try to give some moral support. I wish you much success with your build. I sure you look forward to completing so that you can do what it is you've built this room for :wink: It can seem a daunting, endless process ... would just say, take one issue at a time [while keeping the big picture]. Sounds easy ... but designing and building something like this can be quite a challenge. The margin for error seems minuscule AND expensive !! Great people here! but should it ever come about where you need to ask me a question or relate something about my build, please, do not hesitate! I'm quite confidant that the 'staff' GURU's will keep us on proper course .... thank goodness! :lol: edit: I should proper add ... I don't mean to imply that my rooms acoustical response is 'perfect'. I've tried to build everything accordingly. Gullfo's design was closely implemented [with a minor mod to accommodate the structure I was limited too]. I've done only preliminary REW shoots of the room, and am using different main monitors than when I first started. I can say that the current design and treatment is better than some Pro studios that I've worked [after 30 years ... there's been quite a few]. I can move quite freely about the room with only a slight aberration in the audio [mostly in the far back corner of the room]. At the desk, the lateral/vertical movement is solid with no undulations or skew in the audio spectrum. I am certain that Gullfo [or Soundman] would see exactly how to improve/correct it more once I post REW files. But for the moment, I need to play, study and get my chops back up, and have a chance to really test the translations. I'm hoping that I would then better understand what I'm hearing and how the treatments would be applied and their result ... and hopefully make a bit a of cash doing what I enjoy :) Anyway ... enough with the disclaimer :roll: Just wanted to point out that a single build doesn't make me an expert .... just a student that now has some better sense of what this Science entails. Hey ... look forward to your progress reports !!!!

RJHollins wrote:

Well, I did get some strange looks from the ladies at 'JoAnns Fabrics' :twisted:

:lol: :lol: :twisted:

RJHollins wrote:

This Studio design forum is a godsend. That's why I try to read the postings most everyday

I couldn't agree more, and I try to read as much as I can myself.

RJHollins wrote:

I wish you much success with your build. I sure you look forward to completing so that you can do what it is you've built this room for :wink: It can seem a daunting, endless process

The wishes are mutual ! Yes, it is a daunting process most of the times, especially when facing it all on your own (never even attempted anything of this scale before in my life), but on the other hand as soon as you pass an obstacle and look back at what you've just done it is quite rewarding.

RJHollins wrote:

would just say, take one issue at a time [while keeping the big picture]. Sounds easy ... but designing and building something like this can be quite a challenge. The margin for error seems minuscule AND expensive !!

You're totally right, I discovered too that the secret IS tackling one issue at a time. It's just that sometime looking ahead and seeing how much still need to be done, can make it difficult to keep the focus. For sure, reading here about how other people in your same or similar boat are facing it and receive nice encouragements like yours does give you the much needed push !

RJHollins wrote:

Great people here! but should it ever come about where you need to ask me a question or relate something about my build, please, do not hesitate! I'm quite confidant that the 'staff' GURU's will keep us on proper course .... thank goodness! :lol:

Thank you so much for the offer man (totally reciprocated - without being too conceited :-) ). Really looking forward to read about your progress too ! Ciao Simo

Hi everyone, I've been quiet for some time now, but I have always been following the forum religiously. The building is going ahead very slowly, between work, kids…and I guess breaking my hand in two different places in december didn't really help that :evil: …After 2 weeks of total rest I decided to go out and try to do whatever I could … (covering the broken hand from the dust with the mighty sainsbury's orange plastic bag, thus finding an alternative use from its usual "poop bag" duty :-) ) thanks to the ''even working at the speed of an ant is better than nothing'' approach…I was upgraded to a terminator-like cast - surely this would make me go faster and then was no looking back… well kind of, as it turned out to be quite a challenge to try to frame timber, cut and install rockwool with one hand alone :-) Anyway, now I'm finally recovered and back on track…so here are some pics of where I have managed to take my studio build: First I placed the 100mm 50Kg/m3 rockwool slabs in all the cavity of the inside-out walls. I started with the front right-hand corner, beside the right speaker soffit. After lining the cavity with insulation I managed to squeeze within it two full hight hangers. As the front baffle of the speaker soffit will kind of close them in, the opening under the baffle plate will be the entry point for sound to reach the hangers ("sharing" the same opening to reach the smaller hangers under the speaker plane) I then moved to the Live room and did the 12 degrees angled wall at the left of the room entrance. I completely filled in the cavity with insulation (superchunk style) and placed the rockwool slabs in front of that (i.e. facing the room) Next I made the frame to hang the air con unit for the live room (which I will fill completely with insulation - superchunk again) ... end of part 1... :-)

... part 2 ... I then lined the cavity to house the hangers at the rear corners of the control room and in the live room As the narrow tip of the angled cavity was too small to put in hangers, I cut the insulation with that shape to fill in the gap and placed the rockwool to "close it" Then I made the hangers using Pinnacle pinboard panels as the core, and glued with contact adhesive and tied the 5cm rockwool on both side. I cut a small piece of left over conduit to pass a polyethylene rope through the core for hanging them…perhaps a bit excessive, but after seeing the brittle texture of the fibreboard I thought that it wouldn't kill me to spend and extra minute to do it and make me a bit more at easy knowing that the hangers won't break because of their weight... Being the paranoid person that I am, I didn't trustee idea of using eye bolts / screws to hang up the acoustic hangers. I preferred to use leftover pieces of timber screwed to the frame, cutting a small channel to pass the rope through: … hangers hanged :-) It was great to see what many here have described, i.e. the effect of moving one hanger and causing the other to move as well… cool ! :-) In the meantime my electrician finally installed the electric panel…we got power !!! Next I cut a piece of leftover plywood (i DO LOVE recycling leftovers !!) to go on top of the electric panel. I did that to have a plane, allowing me to sit the triangle shaped insulation within that space, which was otherwise too small to house a hanger (and did the same on the other side for the same reason) ...end of part 2 ...

... part 3 ... Back sloped wall : I filled the cavity with fluffy insulation, then covered that with the usual rockwool slab …same on the corners... and here it is finished (…well, insulated at least :lol: …): Next thing I used a 25mm conduit to pass the speaker lead and clipped the power lead so they are not in the way of the hangers: left speaker conduit: right speaker conduit: Cut the plane where the speaker will rest: left: and right: Then it was the time for the hangers below the speaker plane ... end of part 3 ...

... part 4 ... And finally it was the resonators turn: First I made sure that everything was sealed... above and below I painted the frame in black, so it won't be visible through the black cloth: stapled some garden netting on the back of studs to help hold the rockwool in place (even though this is probably not necessary, as if you pay attention to cut the slab precisely to the cavity measures it does stay firm there…) lining the cavities and loosely filled them with fluffy insulation, and as per usual covered 'em with the ubiquitous rockwool slab: and this is where I am at: well, that's all for now… Ciao Simo

It's looking pretty good! And that's a great idea to paint the front faces of the framing black, to reduce visibility through the cloth. - Stuart -

Thanks Stuart. Always good and a relief to know that you are around to watch my back… :-) Quick question about the speaker soffit construction: If I use 18mm plywood for the baffle plate, would it be ok to use a veneered MDF sheet as the finishing layer over the plywood (it comes in 19mm thickness)? Simo

If I use 18mm plywood for the baffle plate, would it be ok to use a veneered MDF sheet as the finishing layer over the plywood (it comes in 19mm thickness)?

That would be fine. No problem. - Stuart -

aaah, pix! studiobuild porn! thanx simo. broken hands don't make a quick build, sorry for that! I'm in the middle of building corner absorbers myself, will update soon. It make a nice comparison threat :)

Thanks a lot for the "all clear" Stu ! Not at all Ro…yes, I do think that a picture is worth a thousand words, so I'm sharing the pics to give something (good or bad) back to the forum that helped / is helping me so much… I'm following your extremely neat build closely. Great job man! Looking forward to your next update ! Simo

Hi all As the next thing I'll tackle is gonna be the speaker soffit, I'm toying around a bit with a venting system idea before starting. The speaker case (made with 18mm plywood and lined with 5mm sorbothane), is the same height and width of my Genelec 1031A. The case depth is instead 60mm deeper (the maximum I could go before touching the rear framing), to create the heat sink behind the speaker. This is to allow the air to flow from below the plane where the speaker is resting --> behind the speaker --> through the "tunnel" --> to the vent on the front baffle (and timber finish) above the speaker. Now, here comes my question for today: I was thinking of using a rectangular flexible PVC hose that I found as the "ventilation tunnel" (substituting the often used chicken wire) which I think will do a good job keeping the air flow path intact and preventing the insulation getting inside the speaker case.Only thing is that it has a slightly different section than the opening at the top of my speaker case (i.e. 222mm x 92mm). So I was thinking to get around that by building a kind of "vent-to-hose connector" attached to the back and side of the case…here are a few pics of what I'm planning…hopefully they will explain it better than what I'm writing :-) Can you see any problem why I shouldn't go that route? Thanks for your help as always ! Ciao Simo

Looks fine to me! :) - Stuart -

Great. Thanks Stuart :thu: much appreciated

Looking good Simo. Thanks for posting the pics. It is helping me with my design. -Charlie

Thanks Charlie! I'm glad to hear that…pics are very helpful for me too, that's why whenever I can I try to return the favor to the community :-)

Taking advance of a lapse of few decent days of weather I decided to go ahead and box in the fresh air system … (as previously mentioned I was forced to install the fans and silencers on the outside of the building, as the void between outer and inner ceiling was way to small for them). covered them with 12mm exterior plywood and painted to mach the building colour and then I've done the same to cover the air con unit on the opposite side I mean these things are built to live outside, but hey..this is England… and the rain is at home around here, so just a little help :-) ! Simo

I finally decided to dedicate some time to pass the cables between rooms: Here is the design for my wall box: I made three separate conduits. The bigger one is for all the mic leads, the medium one for the data (1x ethernet, 2 x Cat5, 1x BNC, 1x Display) and 2 small ones (1x speaker and 1x guitar leads). The latter ones are basically continuos leads passing through the wall box. The first one is to be able to have the player in the control room and the amp in the live room, the second one is to add the option of having the amp head (with player) in the CR and the speaker cabinet in the LR. I passed some leftover rope inside the conduit as a "fishing cable" for future expansion, probably unlikely but I preferred to cover my back anyway… I cut a 2.5cm section on each conduit and wrapped that gap with a thin piece of soft packing foam to de-couple them and avoid creating a mechanical flaking path between rooms (hoping that the wires themselves won't flank much!). Each entry of the conduits through both leaves were sealed (front and back) to avoid the sound traveling between rooms like an open tube. Firstly I stuffed insulation into each end, then I cut and placed a strip of foam (the one used to fill in expansion joints in walls) around the pipe (like a baker rod) and finally applied a generous amount of caulk to seal the lot airtight When all the wiring was done, i put some soft insulation in the gap between rooms, then mineral wool slabs between studs and covered the frame with the two layers of 15mm gyprock. Lastly, I made a cover for the wall box to keep it firmly attached to the wall. I will cover that with a nicer wood finish (perhaps ash, or oak, or pine…let's see what mr.wallet has to say when the time comes…) Ciao Simo

I cut a 2.5cm section on each conduit and wrapped that gap with a thin piece of soft packing foam

Not so good. I would strongly suggest that you replace that with proper rubber sheeting. That foam has almost no mass at all, and sound leakage into the conduit is going to be very high like that. The rest looks fine, but I would really replace that foam with rubber. - Stuart -

Thanks for your answer Stuart I actually spent a bit of time searching for a material able to close the gap but not linking the two sections of the conduit together, and thought that it was a good compromise :oops: I thought that the priority here was to de-couple them. Actually I was going to use a little leftover of the sorbothane sheet that I'm using for the lining of the speaker case, but than I thought it was "too rigid" and although being a very good material to absorb vibrations, it could have contributed to connect the two conduit sections…. Also, I felt that since the points where the conduit enters both walls are sealed - around and inside it - on the front (from inside the room) and on the back of the plasterboard - it would make it quite difficult for the sound to escape from there and eventually leak in the gap between the walls from the conduit break point. And even if a portion of it does leak, then it would encounter the same "resistance" to get out the conduit on the other wall…(?) …so... I guess I could use that sorbothane leftover, but it would require knocking down quite a bit chunk of wall and redo it…… :cen: let me think……… :oops:

me again :lol: ...while trying to sort out this 'conduit break point', I'd like to start covering all this horrible rockwool as I'm really tired to breathing it. I assume I need to use the thinner plastic layer I can find. So the question are: 1) Can I place this plastic layer underneath the black cloth under the slat resonators as well? Or perhaps is not recommendable to use the "reflective" plastic layer as the slats will already be reflective themselves and instead just use this plastic layer to cover the rest of the rockwool in the room? Perhaps it's better to use something less reflective under the slats (something like the 'batten' used by RJHollins in his build)? 2) Also, can I use the 'weed control matting' (perhaps with fire retardant treatment sprayed onto it) for the "black" cloth under the slats? Thanks as always ! ciao Simo

I thought that the priority here was to de-couple them.

That's the main priority, yes, but you still want a continuous seal, and some mass, and some structural integrity. I would be concerned that if you tried to pull any new cables through there, that thin packing foam would rip. Also, if it is the type of foam that I'm thinking of, it is "breathable", not air-tight.

Also, I felt that since the points where the conduit enters both walls are sealed - around and inside it - on the front (from inside the room) and on the back of the plasterboard - it would make it quite difficult for the sound to escape from there and eventually leak in the gap between the walls from the conduit break point.

You will probably be OK, as long as the ends of the conduit are vary carefully sealed. Right now, you have an open pipe into your air-gap, through the conduit! :shock: So you need to take extra care to seal that: Stuff in as much insulation as you can, around the cables, forcing it down the pipe as far as you can get it, then apply liberal amounts of acoustic caulk over that, to completely seal the end of the conduit. You might even want to put a "putty pad" over that seal too (after the caulk is cured), to make sure that you have enough mass there.

And even if a portion of it does leak, then it would encounter the same "resistance" to get out the conduit on the other wall…

I'm assuming that the thin foam is not air tight, and certainly is not rigid enough to resist the resonances inside the wall cavity, so basically it isn't there, acoustically. sound inside the cavity has a free and open path to both sides of the wall, through the conduit. That's why it is very important that you seal the ends of the conduit on both sides very, very well. To understand the difference, hold a piece of that think foam over your ear, and see how much sound it blocks. Now hold a piece of the sorbothane over your ear, and see how much that blocks... :) - Stuart -

1) Can I place this plastic layer underneath the black cloth under the slat resonators as well?

I would not use plastic on a Helmholtz device (such as a slot wall), since they are based on the movement of air inside the "neck" and on either side of the neck. Putting plastic in there would probably interfere with that mechanism The cloth itself should help to keep the fibers under control.

2) Also, can I use the 'weed control matting' (perhaps with fire retardant treatment sprayed onto it) for the "black" cloth under the slats?

You probably could, but that would probably defeat the purpose! The real purpose of the black cloth is aesthetic: it is there to hide the interior of the resonant cavity, so you can't see the ugly insulation. If you use something that has a wide weave like matting, then you'll still be able to see inside! Use black cloth that is "breathable", meaning that if you hold a piece over your mouth and nose, then you can easily breathe through it, without noticing any resistance to air. - Stuart -

Thanks for the clear explanation Stuart !

Soundman2020 wrote:

You will probably be OK, as long as the ends of the conduit are vary carefully sealed. Right now, you have an open pipe into your air-gap, through the conduit! :shock: So you need to take extra care to seal that: Stuff in as much insulation as you can, around the cables, forcing it down the pipe as far as you can get it, then apply liberal amounts of acoustic caulk over that, to completely seal the end of the conduit.

Honestly, I think I did just that, as you can see on the pic (third from the bottom) on my post in the previous page, which shows the steps of the sealing process you describe here (all in one pic)… 1-open tube, 2-insulation (lots!) inside the conduit all around the cables, 3- foam (just to have a bed for the caulk), 4-caulk (Lots!!!) I might add the putty pad there, as you suggest..…why not?! :-) Anyway, regardless of all of that, I think I'm going to follow your advice and swap that light foam with rubber…just to be safe :-) Ok, NO plastic and NO weed matting on the Helmholtz ! :thu: Grazie Stu !! Simo

Simo, that boxing-in-the-vents is a super smooth plan. And you did a great job, nice skills. It makes the "view" much more pleasant this way, more "one" with the exterior walls. thumbs up. Keep up the good work, and keep the pix comming ofcourse :)