New Basement Studio - Revisited

Hi everyone, I started a thread in september last year introducing a new home studio I'm building, trying to get the most out of this valuable forum... Original thread is here for anyone interested in some background information: http://www.johnlsayers.com/phpBB2/viewt ... t=somalade Since this time quite a bit of work has been done on site and I now have a shell to work with - time to start putting some serious thought into how to make the best use of it. And after 6 months of having all my gear packed away I'm way past withdrawl symptoms! Anyway, much of what has been built so far (room shape, construction materials, etc) has been governed by things not related to the studio itself. Overall though, I think it is a reasonable space to work with. Now I want to make sure I get the best out of it... The main space is approsimately 5.8m x 4.0m internal dimensions, with about 2.65m clear to the underside of the floor joists above. There is a small triangular alcove at one end with the same headroom. At the other end there is a step up of 1.1 m to a raised area with about 1.55m head height. The 3D image below should make this clear. I want to use the room as both a rehersal space for my band, and also as a single room recording studio. I had a few images in my original post showing where the room sits in relation to the house. Below I've posted my attempt at using sketchup to illustrate what I've got. The 3D image should explain the overall space reasonably well and my initial thoughts about how to set things out. There's also a plan showing (very) roughly what I'm thinking in terms of accoustic treatment, etc. The block walls shown are all 200mm thick and have their cores filled (most are also acting as retaining walls). The timber walls shown are currently just 90mm timber stud walls, no linings yet. Their location is however set. There is a 2.0m wide x 600mm high window along one side. The floor is a 100mm thick concrete slab on grade. As I mentioned in my first post, I'm trying to acheive the following: 1. Keep the neighbours happy when the band practices. We practice at reasonable times during the day, so doesn't need to be completely sound proof. Neighbours are very close though (about 3 m away). 2. Get a nice sounding room that will have reasonable acoutics for recording the likes of drums / bass / guitars, but that will also serve as a control room. Want to make sure it isn't too dead, but that when mixing down, the early reflections are under control. I intend to adopt the recommnedation made in my first post of using variable acoustic treatment so I can tailor the acoustics to suit for these different purposes. I'm also planning a bit of a vocal booth. 3. Make the room pretty much sound proof for typical monitoring levels, so that I can mix down at the wee hours of the morning without disturbing people in the house (particularly in the bedroom above the studio, and the one beside it). At the moment I'd like to get some conceptual feedback on what I'm proposing for: 1. Room layout - Desk location, acoustic tratment locations. I'm trying to get more out of the space by mounting the monitors in the area with the raised floor. This will also probably be strorage.. I'm intending to mainly use slot resonators on the rest of the walls as indicated, and probably some bass traps in behind the monitors. 2. Wall construction. My intention here is to hang resilient channel off the block and put either 1 or 2 layers of gib noiseline (either 9.5 or 12 mm th), with insulation in between. Where I have timber walls, I am planing to stick 2 layers of gib noiseline (12.5mm) on the outside face, and build a second separate wall internally, either 1 or 2 layers of gib, with insulation between. How much gib is really necessary do you think in order to achieve what I'm after? 3. Floor - I'd prefer not do do a full suspended floor because of cost reasons and I don't want to use up too much of my headroom. I'm currrently leaning towards providing an isolated platform just for the drums. From what I've read, this will help control the impact noise and bass frequencies due to drums? 4. Ceiling - I'm thinking a suspended ceiling hung off resilient hangers. There is a bedroom above. There are new floor joists to this bedroom - 250x50s @ 450 crs, spanning across the 4.0m dimenison of the room. The flooring above is 25mm thick tounge & groove timber (about 100 years old). How many layers of what thickness Gib would you recommned? How should I look at forming the joint between the ceiling and the walls? Should I look at sloping the ceiling a bit over the control room end of the room? Budgetwise, I'd like to try and keep things below about $5K. Any feedback will be much appreciated! Once I get feedback on the concept, I'll start looking at the details a bit closer (wall / ceiling junctions, window & door treatment, etc).

I’ve been talking with an acoustic engineer familiar with the products available in New Zealand and he had a couple of comments on what I was proposing – I thought I’d share these and post a couple of sketches of proposed details in the hope of receiving some feedback. 1. He has recommended using steel studs (90mm) rather than resilient channel against the block walls. Apparently there can be a problem with certain frequencies resonating when RC is used because of the small dimension between the block and the gib. This problem is less of an issue the bigger the gap because the resonant frequency drops. If 90mm steel stud is used it drops to around 60 HZ. This also seems to tie into graphs contained in a Canadian document I’ve seen referenced in this forum, describing tests on block walls. In NZ there is a ‘Rondo Quiet Stud’ available which assists to give even more isolation between the block and the gib, so this is what I’m planning on going with. 2. Also available here are ‘Rondo Quiet Clips’. These can be used to clip steel ceiling battens to the underside of floor joists. I understand these incorporate neoprene grommets which help provide isolation between the joists and the ceiling battens. Again, I’m intending to go with this, unless anybody suggests any reason not to? One other thing I’m wondering if I should do is provide neoprene pads beneath the bottom track (refer the first detail below). The reason I’m proposing this is that initially I want to try and get away without a floating floor, except for a small floating platform for the drums. If I do decide to put one in at some stage, I would like to make sure the inner leaf of my walls is well isolated from the floor, otherwise this could reduce the benefit of adding a floating floor. If I provide the neoprene it means I can get a decent seal between a future floating floor and the inner leaf of the wall, without shorting out because the wall connects to the floor below. Any thoughts on whether or not this is worth doing?

I've been having a closer look at room layouts and am leaning towards something like what's shown in the diagrams below. I realise though that I'm not 100% clear on a pretty fundamental aspect of the design. Could someboby please clarify the following for me? In the plans below, the heavy black lines represent the inner linings to the walls (gib board). The green dashed lines represent the inner face of acoustic treatment such as slot resonators. Is is OK to have the inner linings to the walls forming a rectangular box , and provide the angles with the faces of slot resonators as in the first plan below, or is it important that the walls themselves are angled as per the likes of what I've drawn in the second image? Also, I'm looking at 7.5 degree angles at the moment (a total of 15 degrees difference in the angle of two side walls). Is this enough of an angle?

Just checking back in - haven't had any responses as yet and its been about 3 weeks since my initial post, about a week and a half since my last. No right to make any demands, I know!... but I have a bit of a construction timeframe that I need to try and fit in with if at all possible, so I would be keen for any feedback on what I've posted so far. The rest of the house has now been pre-wired and plumbed, etc - Insulation will be going in in the next week or so and then linings going up the week after that. If at all possible I want to get the studio done in this same timeframe in order to save costs - it will be considerably more expensive to get the gib crowd / electricians etc back in to do it as a separate project. Can't afford to delay the rest of the house on account of the studio either unfortunately. So.. please, don't hold back!

From my understanding here, the walls should be constructed in a way to help reduce sound transmission. The green area you outlined is for acoustic treatment. (Except for your speaker area) For example, if you built a rectangle room (with the walls already constructed for the best reduction of sound) you could build your soffit design as you have in your diagram (INSIDE the rectangle constructed walls); build 2 slat resonator walls (with EACH wall angling 6 degrees or extending out 1ft per every 10ft) and have bass traps in the rear As for your feedback questions... #2-I'm assuming "gib noiseline" is the same as what we call drywall here. The more mass you can use the better for sound isolation. Two sheets of drywall (gib noiseline??) is a good start. #3 As far as your floor, if you don't want to have a floated floor but want something to help reduce flanking noises check this post out... http://johnlsayers.com/phpBB2/viewtopic.php?t=4845 A platform should help with your drums. There are a lot of threads on here where drum platforms have been built. Do a search or check some studio build threads. That's all I have time to comment on right now. Maybe some of the other guys on here can comment also.

Hi mate, I am just finishing a small studio down in Christchurch and am pretty versed up with what's availiable in NZ for your applications. It's sometimes hard to comapre to the US lingo!! I also used a few things you are planning to do such as Rondo battens etc. (see the site for some photos @ www.peelproductions.net.nz) It's probally easier to chat over the phone if you want to. Just give me a call 021625640. Hope I can help JohnG

Hi Stan & John - thanks heaps for your comments. Stan - OK, so you're saying it will be fine to go with what I'm showing in the first of the two diagrams above? This is definitely the way I'd prefer to do things, although I guess it will require some additional materials because my slot resonators will have to have their own backing boards and framing rather than just constructing them against the internal linings of the main walls. This raises a question though - will the voids between the inner linings of my main walls and the backs of my slot resonators cause any problems? Perhaps through ressonance? Alternatively I guess I can build the rectangular room and build a series of slot resonators against the inner linings of the walls, with depths tuned to the appropriate frequencies, giving an overall 'saw tooth' look, as shown in the diagram below. This would also take up less space. Any thoughts as to which is the best way to go? Yes, gib is what you call drywall. Gib noiseline is a special type of drywall with an increased density and it also contains fibres - it is more effective than our standard gib plasterboard for stopping sound transmission. I'm currently proposing 2 layers of 12.5mm thick board (ie: total of 1 inch) - I guess I can put this up and see how well it works, and add another later if necessary. OK, some kind of rubber product on top of the concrete slab souds like a good idea. I'll do some research and see what is available in NZ. I know there are some 'engineered' accoustic products available for this type of application. In terms of floor finishes, I'm looking at simply putting a layer of rubber down, covered by sheets of particle board. No additional covering on top of this. Do I need to do anything to fix the particle board sheets together? Perhaps just glue them down the edges? Or should I also glue to the rubber underlay? John - thanks for your post too - I'll definitely give you a call. I'm in Malaysia at the moment but will back in NZ in about a week so will give you a call then.

solamade - I'd do something like this using the angulat rear as a bass trap and opening up the front for a booth. cheers john

John If you see this, I was just curious... Was there any particular reason for no bass trap in the left rear of the diagram you drew up? Space related problems or something?? Thanx!

Hi John, Thanks heaps for your feedback. I have considered something similar to what you've proposed but as it turns out I don't think there is quite enough headroom to make a vocal booth practical in that location. Refer my first post above: "At the other end there is a step up of 1.1 m to a raised area with about 1.55m head height. The 3D image below should make this clear. " So things are a bit tight at that end - this is why I was thinking I could at least make use of the space with the raised floor by putting the speakers there and turning the rest of it into bass traps - although I'm not sure how effective it is for this given that it isn't full height? In other aspects though it looks as though what you're proposing is similar to what I'm looking at. so that's encouraging. Refering also to the question in my 3rd post above - can you please confirm whether the light brown coloured angled walls in your image are the inner walls of the room shell (ie, timber framed, clad in drywall), or if these are the acoustic treatment. I'm still not 100% sure whether or not I should angle in the inner walls, or whether it is just as good to have these walls parallel, and provide the angle with the front of the slot resonators. Jonathan (somalade)

This raises a question though - will the voids between the inner linings of my main walls and the backs of my slot resonators cause any problems? Perhaps through ressonance?

I wouldn't think so. If the resonators are built correctly I believe they should be ok. I would think with the insulation inside, unless something is "loose" most high and mid frequencies should absorb or possibly reflect with the exception of your lows. I've never saw any comments on here of a resonance problem from a built slat resonator.

OK, some kind of rubber product on top of the concrete slab souds like a good idea. I'll do some research and see what is available in NZ. I know there are some 'engineered' accoustic products available for this type of application. In terms of floor finishes, I'm looking at simply putting a layer of rubber down, covered by sheets of particle board. No additional covering on top of this. Do I need to do anything to fix the particle board sheets together? Perhaps just glue them down the edges? Or should I also glue to the rubber underlay?

Be sure to check the rubber material you will be using. I would think you would want to have a material with good "dampning" qualities. (unless it's butyl sheeting...and even if it is, I'm not sure if there are different "kinds" of butyl sheeting. I was planning on doing some research in this area and asking questions as I got nearer to finalizing my exact floor plans) Also, be sure to do the "test" Knightfly suggested concerning moisture. As far as how to secure the particle board I'm not sure. Maybe someone on here has a suggestion. If not, maybe Steve (Knightfly) or even John himself may tune in and offer a suggestion. I'm going to look into this because I'll be doing this same thing. I'll let you know what I find out. One thing that may help you...From my reading on here, building a room for sound isolation and for acoustics are 2 different things. I would think to some degree they work together though. Once you are done buiding your inner and outer walls to reduce sound/noise from entering/exiting your room, it's then time to control the frequencies travelling all around your room from your speakers which is what the acoustic treatments of traps and absorbers do. In the case of a slat resonator wall, I would think it wouldn't matter if the inner walls were rectangle (in your case) as long as each side wall slat resonator was angled 6 degrees or more to control/deflect standing waves and there were other treatments in the room to absorb or reflect as needed. I have no doubt if this is a wrong assumption I will be corrected! Hey, I'm still learning myself. :) Hope some of this helps...

I've looked a bit further at the slot resonator design and I think I now understand something that wasn't clear to me before. I had it in my mind that the slot resonators would only be a couple of hundred mm deep at the most, but having done a few numbers, it looks at though there is no reason why they can't tapers from 100 mm deep to say 500 mm deep. If this is the case, I can go with a layout similar to the first image in my 3rd post above (StudioLayout2.jpg), and the entire gap between the heavy black line and the dashed green line on the side walls becomes my resonator. Does this sound resonable? I had been thinking I would have to make an additional wall at the back of my resonators in order to keep their depth down, but it looks like I had the wrong end of the stick.

Thanks heaps for your comments Camistan, and thanks also JohnG for your advice in our conversation the other day. It was great to be able to talk to someone who's been through all the stages I'm currently working through. I've been looking further at acoustic insulation products available in NZ and I'm not sure if there is anything here equivalent to Owens Corning 705. It seems the most dense 'Rigid fibreglass' available here is a product called Siliner (for lining airconditioning ducts). It has a density of around 45kg/m3. This is roughly equivalent to Owens Corning 703 from what I've read, but 705 has a density of about 90kg/m3. Does anyone know of any equivalent products available in NZ, or should I just go with the Siliner (or equivalnet polyester based product).

Hi Jonothan - sorry I didn't notice the raised floor at the front - pity - It was my intention to use the triangle at the rear as a bass trap. Yes - the slots create the angled wall with teh space behind being the cavity for the slot. So you get an absorber AND and an angled wall all in one. For your floor whynot use what we call yellow tongue - it's a standard flooring particleboard that has tongue grooves in the side and they give you a length of plastic to act as the joiner - check out the floor in the studio in the container thread. The insulation you mentioned (i.e. aircon duct liner ) is the correct type. Can you get Insulco over there?? cheers john

Hi John, Thanks for the clarification - I'm feeling reasonably comfortable now that I'm on the right track which means I can go ahead and get the basic shell completed along with the rest of the house (ie: line the inside of the blockwork and ceiling and construct and line the double stud walls. My intention is to construct the vocal booth at a later stage. The yellow tongue product looks to be exactly what I'm looking for for the floor - I'll see what equivalent product I can track down here. Alternatively I have a friend with a 'biscuit' machine that I could use to create this detail with standard particle board. I don't believe that Insulco is available here - I'll do some more research - although from my Google search it does look as though an NZ company (Fletcher Building) has recently bought Insulco / Tasman Insulation Australia?? This might mean the product becomes available here soon. Confirming then what I am going to go ahead with: 1. Blockwork walls - Gib Rondo Quiet stud (90mm) fixed to walls, insulation, then 2 layers 12.5mm Gib Noiseline. Fixed and with accoustic sealant as per Gib specifications. For the insulation here I am planning to use Pink Bats Silencer rather than the Siliner (which is rigid fibreglass equivalent to Owens Corning 703). It is significantly cheaper and I figure these walls should perform reasonably well given that one of the mass layers is a solid filled 200mm block. 2. Timber framed walls - 2 separate walls with 90mm separation between studs, 2 layers 12.5mm Gib Noiseline each side. Insulated with 100mm thick Siliner. Gib Quiet ties to restrain the top of the inner wall as these won't extend all the way up to the floor joists. 3. Ceiling - Rondo Quiet Clips off the existing ceiling joists, supporting Rondo steel battens. 2 layers 12.5mm Gib Noiseline. 100mm Siliner insulation. I also plan to glue a single layer of standard 10mm Gib to the underside of the exisitng T&G floor boards (between the joists) and seal around the perimeter. 4. Floor - AUL Acoustop underlay, 20mm(?) particle board on top (with biscuit detail to join sheets). As I'm planning to get this all completed in the next week and a half (except for the floor), please speak now or forever hold your peace! In the mean time, a couple of questions that I'd be keen for quick answers on if anyone is able to help: 1. Any chance I can substitute the 100mm Siliner in the timber framed walls or ceiling for either 50mm Siliner or Pink Bats Silencer, while still meeting my performance objectives? This would save me $$ - Siliner 100mm is about $95 per sheet! (2.4m x 1.2m) 2. I'm planning on running all my wiring internally in cable tracks. I figure this will all be covered up by accoustic treatment anyway and means I have more time (& flexibility) to get it sussed out properly. Not to mention the benefit of less penetrations through the inner wall linings. Thanks again for your help everybody! I'll try and get some photos up in the next couple of weeks...