Small control room - Minuscule Studio

Hello forum - here comes a small project from Denmark. I have been reading this forum for a while, but now I need to get started with my design, so here goes: My goals: A studio for mixing and occasional recording (vocals, guitar, synths - that sort of thing). I want to focus on building it like a control room, since I have access to a friends' studion for serious recording. The setup will be the typical DAW, with some outboard added (preamps, compressors). Also, I will be putting my guitar amp and some synths in there. I've got this one room to dispose of, so most of my gear has to go in there. The room: - Is located in the basement of our home - a brick building from the mid-fifties, typical for this area. Most of the room is under ground, about half a meter is above ground. All walls are solid brick,the floor is solid concrete, but the ceiling is the usual plaster > straw > wooden boards. It does not provide much soundproofing with respect to the living room above. Features of the room: - Measures 348cm (W) by 472cm (L) by 208cm (H) - Our heating installation is in there, as can be seen on the pics. It does make some hissing noises now and then, which must be remedied. - The basement location means I can't take any chances regarding moisture in the walls and floor - whatever I put in there, will need to be spaced away from the walls for ventilation to be possible. The floor will remain uncovered. - The wall with the window will be the front of the room, as I cherish the little bit of sunlight I get in. How loud? - I have decided that I won't be doing any soundproofing of the room due to the space constraints. A possible exception would be to beef up the door somewhat, to reduce leakage that way. - Because of this, I will only be playing my mixes loud when I am home alone. I might build an isocab for the guitar amp though. Let's just say, that if I get complaints, I will turn it down. Budget: I am thinking under 500$ - I have access to a lot of secondhand building materials (mostly construction wood) and I already have a few bales of 4 inch rockwool. Also, I have access to a lot of different tools, so I can do all the work myself. My thoughts so far: From what I have read here so far, it looks like John's Small Studio might be a good place to start. I see a copuple of caveats though: - Corner traps cannot easily go all the way to the ceiling in any part of the room, due to the heat pipes. This goes for speaker soffits too, which I would like to have in my room. A solution could be to build them to just under the pipes, and then make some kind of wall/ceiling traps - or just ignore the pipes altogether. - The heating installation which can be seen as the criss-cross of pipes and stuff on the wall in pic 2, isn't completely quiet, so I would like to somehow construct any rear-wall absorption to also kill the noise from that installation. Whatever I build, could go all the way out in the room to just before the doorway. That should leave room for hangers, resonators or some other type of trap/absorption. - The radiator on the rear wall probably should be moved to another location. It will complicate the project a bit, But I think I know someone who could do it for me. - The issue of moisture from the walls. If I build speaker soffits and slotted resonators like in John's model, could I not simple offset them an inch from the wall? The boxes will still work as intended, won't they? - I have thought about making a ceiling cloud, but it won't be more than 4 inches all in all, with 2 inch rockwool and a little over an inch of air. Will that be worth it? Does the cloud have to cover the entire ceiling? That will be difficult due to the heat pipes. - The chimney in the corner (can be seen in pic 3) messes up the symmetry of the room.Should I build a similar structure in the opposite corner (please say no!)? That is all I can think of right now - I hope a few of you folks have time to take a look! Christian.

welcome! nice first post! it is possible to build some components - soffits, slats, traps etc to fit your space and leave an air gap around the periphery. on the ceiling - it might be possible to add a layer of drywall get the mass up although it would be more useful to add some greenglue although your budget prohibits that. on the door, adding some MDF and sealing it will help. the cloud will definitely be a necessity over the desk and you might find you need a hard backed cloud angled over the mix area to get things right. the window - you might consider a small frame to sit in it and then some MDF or glass to beef it up and seal it. the glass would let in some light it that is desired plus if it's hinged, allow it to be opened. on the back wall treatments, a framed wall with access panels or doors for the plumbing should be used to isolate the noise and heat. you might consider some way to vent the heat off into another room - small flex duct / fan. plus factor all this into any need for fresh air exchange with your space. maybe a baffle box hung on the outside of the door could do it? or in the window opening?

Hi Glenn - Yeah, MDF would probably help on the door. I guess I could put some drywall in the ceiling, but even if it only eats half an inch, it all adds up. The question is: Do I need the cloud more than the soundproofing? Speaking of the cloud: When you say angled, is that 6 or 12 degrees? Only over the mix position? The more I angle it, from the front of the room, the less light I get from the window. Could I angle the ceiling to the sides of the window, and then let the ceiling in front of the window stay flat? Also: What is a hard-backed cloud? And why choose it over a spaced absorber? About the heating installation: I only want to kill the noise - it gets quite cold here in the winter (and much of spring and autumn) so there has to be a heater in there - but it would work better under the window, to get some convection going. More questions: There seems to be a lot of differnt types of absorption/trapping around. From what I have read of recommendation for small rooms like mine, it seems diffusors make little sense, but apart from that, it all seems open. I think I get why John's Small Room uses slotted resonators and other broadband absorbers, but what about hangers? Running my room dimensions through Ethan's Modecalc, I see a lot going on - especially between 300-500 hz, which I would probably try to cure with broadband devices. Hangers seem more elusive, in that no one seems to know exactly what they do, and how to calculate their sizes - but what about experience? I have heard it said that you can never have too much basstrapping in a room, but the question is how much actual bass resonance I can hope to attenuate in a room as small as mine - while still leaving space to work in and for broadband devices? Will I see diminishing returns going for hangers over something like slotted resonators for instance? None of these absorbers or traps are hard to make - but how much of which? Some more than others? Some not at all for a room like mine?

if you need isolation and adding the drywall layers will help, then that should be step one. the isolation wall on the plumbing side is to help with the system noise getting in, not your sounds getting out... obviously leave whatever elements you need exposed to provide the necessary heating. the hard backed cloud is a panel with an absorptive front (and/or back) which runs interference with the floor-ceiling modes. in your room, it will be helpful. my preference is generally angled slat resonators for the side wall treatments, cloth covered absorption front and back and scattered as needed to get the frequency and reverberation levels balanced. the angles help keep the front alive and reduce interfering reflections off the sides. soffit mounting is good and using John's component style to build up the necessary units will mean you can build up over time.

Hmm...you got me considering that drywall for the ceiling. The cloud again: 1. We are simply talking about a panel made from cloth covered mineral wool (or similar), hung from the ceiling over the mix position and desk? If it has an absorptive front - why angle it? 2. Or something a bit different? For absorption back and front - wouldn't a setup with hangers behind a cloth screen also give some high-frequency absorption? After all, it is an open box with quite a bit of mineralwool in it. Again, I am confused as to whether I should build some hangers, or focus solely on what seems to be called broadband absorption around here. Angled slat resonators: Can I target the modes supposedly present in my room, according to Modecalc - if I put them in the Helmholtz calculator spreadsheet and then proceed to build a slat resonator that targets these frequencies? Would it be logical to put the slots/slats tuned for the lowest frequencies closest to the ceiling and floor corners - since this is where you would put broadband traps anyway? Or doesn't it matter where I put which slats? The more answers I get, the more questions I have! Thanks for putting up with it so far. Christian

the cloud angle gives it a bit more range in the frequencies, and if later it needs to be a hard cloud (meaning a layer of plywood/MDF behind the absorption) because of a floor-ceiling mode, then it will have more impact. i think given the size of the room, you'll find building out the hangers may be tough versus just cloth covered absorbers. the slats should be broadband and will help with the angles you want to create the reflection free zone.

Ok, I think I get the concept of the hard cloud now. I guess if I change it from a "soft" cloud to a hard, then I also change it from a broadband absorber to more of a high band device? I mean - by "removing" the space behind it with the mdf? Hangers: Maybe I'll just settle for the hangers in the soffits and see what they do.

The cloud remains a broadband absorber, the hard, mass backing alters the (local) floor ceiling room mode and the angling serves additionally to deflect the soundwaves away from the listening position (RFZ). Without the hard backing it is a simple broadband absorber and the angling varies the distance of the absorber to the hard ceiling thus helping to extend the frequency range (in the lower registration).

I'm back - after doing some more drawing and thinking. @BriHar: thanks for that explanation. It makes sense in my mind at least. The following drawings are of the speaker soffits, slat/slot absorbers and the angled cloud - as I picture them. The cloud has an angle of 12 degrees, and slopes from somewhere around the back of my table, to somewhere behind the mix position. The funny thing 1320mm above the floor - is my head. Clearly. The lowest point of the cloud dips somewhat under the upper part of the window, which eats some of my light, but what the heck. Soffits and absorbers go from the floor, to right under the pipes running in the ceiling/floor corners, as mentioned in my original post. I might put absorbers over the pipes - and I might not. We'll see. The speaker setup is not quite a 60 degree triangle as you can see - I wanted a bit more floor space, without having to sit smack-dab in the middle of the room, length-wise. Any problems with this setup? My main worries right now, are that my speakers won't work in the soffits - they have the port firing out the rear. But from what I have read, I'll just need to try it and see. I think that's it for now. Comments? Christian.

what type of monitors do you have?

Well, they're JBL, two-way speakers, but on loan to a friend right now (and for the past 5 years - but ending today) so I can't really remember the model. Will get get them back today and find out. But I was thinking that I might go so far as to make new cabinets for them, with a forward pointing port - if it is possible. The thing is, they have the drivers mounted asymmetrically on the baffle - but the two speakers I have are the same. So I guess I have two right-side or left-side speakers. Annoying. A new cab could remedy that too. They sound pretty good to my ears, I have used them lots in my friends studio. But I might be able to get a good deal on either Tannoy 601A's or Dynaudio BM5 II's, if the JBL's don't work out. Don't know how the other speakers will fare in soffits though. It is my understanding (from reading lots of threads on it) that rear-port speakers can work - as long as you don't "choke" them. They have to have room to breathe behind the soffit, right?

correct, leaving vents in the speaker box to allow them to vent, especially true if they're also powered. the layout asymmetry could be a challenge but if you've been mixing with them and being success it might not be a problem for you.

The speakers are HP6B's - some type of passive hifi-speaker from the late 90's. In comparison to the tannoy's my friend just bought, the JBL's sound less bright. Don't know how linear they are. The spec sheets says 57-20,000 hz, -6db. That is not too hot, I guess. But I suppose that if I can make these work in soffits, then I might also be able to make Dynaudio BM5 II's work (as they're rear-firing too). What I can't seem to get my head around (with soffit-mounting rear-port speakers) is the balance between letting the port "breathe" - and letting it play into my room. I mean, the way I see it, the ports should fire into a reasonably large cavity, lined with insulation material, or else there will be a pressure building up inside the speaker cabinet, which the port is supposed to release. Correct? So at what point is the whole point of the soffit compromised? Just wondering.

in general, your soffits should have enough space to let them work. the baffle step effect will increase the speaker LF response about 6db. so the trade off between the rear port and the baffle step will help equalize and the venting in the soffit as well as the overall configuration of absorption in the space will not necessarily prevent the rear facing port from contributing (or detracting depending on the time involved) to the LF response. so having enough absorption in the soffit is more important than less to ensure a balanced response. the HP6B are fairly small speakers as are the BM5 so you might be able to mount them both (top to top - to match the acoustic center as closely as possible) in the soffit.