Nightmare room, can I get it to work?

Hi guys Long time lurker and first time poster here. I've read Rod's book cover to cover and have studied many posts here and on Gearslutz. I know everyone says it, but really, thanks for such an amazing resource, I've learnt so much. I've just moved house and need to set myself up a new writing / mix room, then a basic recording space doubling as chill out room. Writing / mix room is the priority time and spec-wise - I do very little recording (only my piano / occasional ac gtr / vox, quiet stuff) so the live room can wait and does not have to be pro spec. I have ummed and arred about building the mix room into a log cabin in the garden (planning complications, would be small) or converting my garage (no light and I could really do with a garage), so the best place is a 8.3m x 4.2m x 2.3m ground floor space currently designated as "games room" and "office" at one end of the house. Budget ~£7k. Sketchup file attached. So as you will see the main problems / considerations are: - room dimensions are close to multiples of each other - a big hole aka cellar at one end of the room! - wood flooring on joints throughout - my wife who will be sleeping upstairs :o I'm happy to refrain from recording instruments at night, but would like to be able to work in the writing/mix room. Currently 80dB in front of my speakers ends up as 40dB upstairs, silence is 27dB (iPhone measurements). There is a beautiful view out on the cellar side, and a small amount of road noise on the office side despite double glazing. Footsteps / creaks can be heard through the ceiling. So my main starting point was to ask whether to build a one-room studio, or to separate out the mixing and recording rooms. A one-room solution would be great for me, but if the problems generated by the resonant cellar will make for a shitty room then I would prefer to have a separate mix room isolated from the cellar. What's better, a 60m3+ one-room solution with potentially nasty modal resonances, or a 25m3 room with decent isolation/acoustics? Here are a few designs I have sketched up. Design 1B is Louden 1:1.4:1.9 ratio. Feeling good about this one. Design 2 is bare bones without accurate dimensions, but is this layout better? Design 3 is my feeble attempt at a one-room layout. Floor So if I build directly onto the current floor the whole thing will resonate isolation will be compromised. Not knowing much about UK building regulations, how feasible / advisable is it to rip out the flooring & joists and fill with concrete? Are there damp / ventilation complications that I need to know about? If I go for 2 rooms, would an isolated concrete slab isolating the mix room from the rest of the floor & cellar be the best solution? Would there be any point concreting up to the edge of the cellar? Cellar Massively problematic, I know I know, like having a big bass drum under the floor! No doubt placing my speakers on top of the void would be a disaster, but could they work at the other end of the room with decent trapping? Is there a way to treat it so it's less problematic but I still have somewhere to keep my wine ;)? I could stuff half the space with trapping. If I'm recording quiet / non-bassy instruments near it will it have a tangible effect on recording quality? Ceiling Will remove current layer of drywall, then thinking of following Rod's advice and loading up the ceiling mass with strips of drywall +caulk +rockwool between the joists. Then isolated timber 2x4 frame with 50mm fibreglass and 1 or 2 layers of 3/4" drywall +caulk on the inside. Does this sound like overkill/satisfactory/insufficient for my 53dB reduction requirement? Walls As ceiling construction, but will a gap be needed between the structure and the exterior wall if my concern is sound transmission upstairs rather than outside? Double glazing on the internal window, or will this create a 3 leaf system? Bit confused about the wall arrangement between control room and live room, would that second stud wall be useless without the whole live room being room within a room construction? Sorry for the flood of info and questions on the first post. I'd be so grateful for some help with all this, if anyone would be kind enough to chime in. Thanks a lot! Harry

Things I forgot to mention.. You enter the cellar through a hatch in the wooden floor The floor construction is one big steel running lengthways down middle of room, joists lie width-ways on top, then T&G hardwood boards lengthways on top of that.

I was hoping my exhaustive description would be helpful, but I fear it may have been a bit too exhaustive! So apologies if there are too many questions. Maybe I could request some opinions simply on two specific fundamentals.. - can I make a 1 room design work with my isolation requirements and tricky dimensions, or should I go for 2 rooms with small fully isolated mix room? - is there anything I can do with the cellar space to negate it's acoustic contribution? (next to filling it in!) Thanks so much. Harry

Hi there "hazza26", and Welcome! :) Man, have you ever been patient waiting for a response! Sorry about that...

so the best place is a 8.3m x 4.2m x 2.3m ground floor space currently designated as "games room" and "office" at one end of the house.

That does sound like a good space, except that the ratio isn't so hot. But that can be fixed.

- a big hole aka cellar at one end of the room!

Do you need access to that, or can you just close up the hole and forget about it?

- wood flooring on joints throughout

Not so good... :(

Currently 80dB in front of my speakers ends up as 40dB upstairs,

:shock: :!: Ouch! You need quite a bit more isolation then.

iPhone measurements

:? :roll: Not to be trusted. You really should get a decent sound level meter and measure that properly. A phone cannot do the same job: that's a simple little US$ 2 microphone in there, which is highly directional, limited bandwidth, designed for voice mainly. What you need is a proper omnidirectional mic, with flat response across the entire spectrum, and designed to do the job of measuring sound pressure levels, not voices. You can actually get such a mic that plugs in to your iPhone, and that makes it far more usable (I have one for my Android phone), but even then you need to calibrate it against a meter, and the cost of the mic is about the same as the cost of a used good-quality meter anyway, so it makes more sense to just get a meter.

a small amount of road noise on the office side despite double glazing. Footsteps / creaks can be heard through the ceiling.

:shock: :!: Oops again!

What's better, a 60m3+ one-room solution with potentially nasty modal resonances, or a 25m3 room with decent isolation/acoustics?

I would go for the larger room for sure, then build a proper "room-in-a-room" inside it, with a good ratio and good treatment. It would still end up larger than 25 m3, and sound loves space!

Here are a few designs I have sketched up. Design 1B is Louden 1:1.4:1.9 ratio. Feeling good about this one.

Looks good, but I would move the window so you have direct sight lines from the mix position to the LR. And I would also soffit-mount the main speakers. You need to move the listening position further forwards anyway: you are pretty much smack in the center of the room as you show it now, which is right where all the biggest modal peaks and nulls are. Not a good pace to put your ears... But have you considered a corner control room? It loos like it would work well with your space.

So if I build directly onto the current floor the whole thing will resonate isolation will be compromised.

Yup.

Not knowing much about UK building regulations, how feasible / advisable is it to rip out the flooring & joists and fill with concrete? Are there damp / ventilation complications that I need to know about?

Or maybe just pour a concrete floor, instead of the wooden floor. Not perfect, but a lot better, and a lot cheaper than just filling the whole thing.

If I go for 2 rooms, would an isolated concrete slab isolating the mix room from the rest of the floor & cellar be the best solution? Would there be any point concreting up to the edge of the cellar?

You cold do that, but once again a properly isolated concrete slab floor ain't gonna come cheap.

Cellar Massively problematic, I know I know, like having a big bass drum under the floor! No doubt placing my speakers on top of the void would be a disaster, but could they work at the other end of the room with decent trapping? Is there a way to treat it so it's less problematic but I still have somewhere to keep my wine ;)? I could stuff half the space with trapping. If I'm recording quiet / non-bassy instruments near it will it have a tangible effect on recording quality?

To be honest, I think the cellar is your best option! Just build a proper "room-in-a-room" structure, carefully dimensioned, and properly treated. 60m3 is plenty of space to put in two rooms, I would think.

Ceiling Will remove current layer of drywall, then thinking of following Rod's advice and loading up the ceiling mass with strips of drywall +caulk +rockwool between the joists. Then isolated timber 2x4 frame with 50mm fibreglass and 1 or 2 layers of 3/4" drywall +caulk on the inside. Does this sound like overkill/satisfactory/insufficient for my 53dB reduction requirement?

Sounds about right, if it is done as part of the complete isolation solution.

Walls As ceiling construction, but will a gap be needed between the structure and the exterior wall if my concern is sound transmission upstairs rather than outside?

Yes. The isolation shell needs an air gap all around, on all five sides (four walls plus ceiling). Sound travels in all directions, not just the ones you want it to take... :)

Double glazing on the internal window, or will this create a 3 leaf system?

Yep, that would be 3-leaf...

Bit confused about the wall arrangement between control room and live room, would that second stud wall be useless without the whole live room being room within a room construction?

Assuming you build then both in the cellar, you build each one as a complete stand-alone structure, and they do not touch each other, or the existing building. Each room is just a stud frame with drywall on one side of the studs. It is that simple. Stud framing for the walls, joists across the top for the ceiling, drywall everything, and you are done.

I was hoping my exhaustive description would be helpful, but I fear it may have been a bit too exhaustive! So apologies if there are too many questions.

Not at all! More info is always better! It's just that sometimes response can be slow here on the forum, when there are a lot of active threads and not too many people responding. - Stuart -

Stuart Thank you so much for the detailed response, absolutely no need to apologise for the delay :D

Soundman2020 wrote:

a big hole aka cellar at one end of the room! Do you need access to that, or can you just close up the hole and forget about it?

I would really like to keep on using it if possible, unless keeping it will totally screw my recordings.

Soundman2020 wrote:

iPhone measurements Not to be trusted.

Advice duly noted, I will organise an upgrade!

Soundman2020 wrote:

What's better, a 60m3+ one-room solution with potentially nasty modal resonances, or a 25m3 room with decent isolation/acoustics? I would go for the larger room for sure, then build a proper "room-in-a-room" inside it, with a good ratio and good treatment. It would still end up larger than 25 m3, and sound loves space!

Yep, but it's just a question of whether it will work with my floor structure.. see below.

Soundman2020 wrote:

Here are a few designs I have sketched up. Design 1B is Louden 1:1.4:1.9 ratio. Feeling good about this one. Looks good, but I would move the window so you have direct sight lines from the mix position to the LR.

The window is an external one. As I say I record so rarely I think I can safely bypass sight lines to the live area, I would rather have a cosy writing space.

Soundman2020 wrote:

And I would also soffit-mount the main speakers.

Ace, I've been doing lots of research into this and this is the nod I've been waiting for 8)

Soundman2020 wrote:

But have you considered a corner control room? It loos like it would work well with your space.

I must admit I hadn't. It seems like all the designs I've seen are in bigger rooms than mine, with booths etc to the left and right of the control room. I'm trying to think how I can design a corner layout without wasting a load of space either side. Don't suppose you have a link to a corner 2-room setup?

Soundman2020 wrote:

Not knowing much about UK building regulations, how feasible / advisable is it to rip out the flooring & joists and fill with concrete? Are there damp / ventilation complications that I need to know about? Or maybe just pour a concrete floor, instead of the wooden floor. Not perfect, but a lot better, and a lot cheaper than just filling the whole thing.

Would you mind expanding on this a little? How does this differ from my concrete slab drawing below?

Soundman2020 wrote:

a properly isolated concrete slab floor ain't gonna come cheap.

I think my (Rod's!) design below is considered an isolated slab, is that expensive?

Soundman2020 wrote:

To be honest, I think the cellar is your best option!

Crossed wires... the "cellar" is the crappy 1.4m high crawl space UNDER the live room. On the right of the drawings below.

Soundman2020 wrote:

Walls As ceiling construction, but will a gap be needed between the structure and the exterior wall if my concern is sound transmission upstairs rather than outside? Yes. The isolation shell needs an air gap all around, on all five sides (four walls plus ceiling). Sound travels in all directions, not just the ones you want it to take...

Will a gap between int structure and ext walls really make a difference to the sound travelling up through the ceiling? I agree a gap in the ceiling will. Sound going through the side wall is not a worry.

Soundman2020 wrote:

Double glazing on the internal window, or will this create a 3 leaf system? Yep, that would be 3-leaf...

Ok, even if I'm only concerned with sound travelling through the ceiling, not through the external window? So I did a bit more detail in Sketchup for how things are now and one idea for how I could separate out the rooms. This was my solution to how I could keep the cellar and not have to rip up the entire wooden floor, but still create a decent working / mix environment unaffected by the cellar/floor resonance and well isolated. Drywall inside frame, window & door in control room not yet drawn. Remember control room needs decent isolation so I can work at night, "live" room aka after hours hang-out room would benefit from a little extra soundproofing. I won't be hammering on the ivories at night. I was thinking resilient channels on the live room ceiling and wall adjoining the control room. Drywall strips and fibreglass between ceiling joists all along. Ceiling height maintained in live room, would acoustically treat and could pad out half of cellar with rockwool if it would help. But I would still love a single space if it's possible to build an isolated room on top of the cellar. Could it be done or would solid concrete floor end to end be the only workable solution?! Also I'm feeling like the amount of window real estate would be a problem, could I build successful treatment with those big windows at either end :? Thanks again, sincerely, for your help - massively appreciated and a donation will be forthcoming! Harry

Crossed wires... the "cellar" is the crappy 1.4m high crawl space UNDER the live room. On the right of the drawings below.

Ahhh! :oops: OK, I get it now. I thought there was a proper cellar down there some place, in addition to the hole...

Will a gap between int structure and ext walls really make a difference to the sound travelling up through the ceiling? I agree a gap in the ceiling will. Sound going through the side wall is not a worry.

Well, yes it will make a difference. MSM isolation is a system, and it all works together. Since the cavity between the walls is also open to the cavity between the ceiling, there is interaction going on: the resonance, and the sound in general that gets into the wall cavity can also make its way into the ceiling cavity, and vice versa.

Ok, even if I'm only concerned with sound travelling through the ceiling, not through the external window?

Think of it like this: I want to build an aquarium, so I get a metal frame for making one, then I decide that I only really need to worry about the side that faces the room, so I can see the fishes: So I figure I only need to put glass in one side of the frame, as that's the side I'm worried about, and I can forget about the other sides... How well do you think my aquarium will hold water? :shock: :D OK, so that's extreme: To make it more like a studio isolation analogy, let's say I decide to fill in the other sides too, but I use cardboard, instead of glass, since I'm still only worried about the front... Get the point? :) Isolation is an "all or nothing" proposition. It works exactly like the aquarium analogy: even though you might only be interested in stopping sound leaking out one side, you still have to do all sides of the room to the same level of isolation, just like you still need glass in all sides of the aquarium. An isolation system is only as good as the weakest link, just like the aquarium will only hold water as well as the weakest side.

But I would still love a single space if it's possible to build an isolated room on top of the cellar. Could it be done or would solid concrete floor end to end be the only workable solution?!

It should be possible, since nobody lives down there, so you won't be bothering them too much with noise! Also, it's a sealed space, with no other entry/exit, so there's no issues with sound getting out another way. However, it is could act like a rather large resonant cavity, so you'd have to be careful how you did it, but it should be possible.

Also I'm feeling like the amount of window real estate would be a problem, could I build successful treatment with those big windows at either end

Is it physically possible to do that? Yup, it sure is. Is it cheap? Nope, it sure ain't. :) In other words, as long as you don't mind spending the money, then you can do still do it, probably. - Stuart -

Hi Stuart - just to say thanks for the reply, sorry the notification must have ended up in my spam. Still mulling over the options, I get the feeling I may be wise to spend some money on a studio designer at this stage. But thanks again for all your input, very much appreciated. :D

Harry, I just sent you a private message (PM) with a few comments, so please check your messages. - Stuart -