Planning my small, external studio room

[rominronin]

I’m a Londoner who moved to Austria, I know of SoundMan2020 through the JLS forums and only recently discovered this forum while researching soffit mount construction (and found Gareth's excellent Timelapse videos on youtube).

I FINALLY have time to devote to working on my music space. There’s an external building in the back of our garden, of which the raw, unfinished internal dimensions are:

Width: 400cm
Length: 430cm

The ceiling is sloped:

Min height: 215cm
Max height: 255cm

Entrance is via a door on the side, at the tall end of the room:

Area: 17.2 m2
Volume: 40.42 m3

I want a space for (prioritised):
1. Producing music (mixing ITB, overdubbing)
2. Recording music
3. Listening to music (Spotify, Vinyl)
4. Song writing
5. Working on other pastimes, such as:
- DIY mechanical keyboard
- Podcasting
- Twitch streaming
- Recording/producing videos

One room, not two right? …Right?
I work with musicians and singer/songwriters, and I always wanted the flexibility that an isolated live room provides during the recording process. Unfortunately I don’t have the volume of space to really split the room into a ‘proper’ live room/control room set up. HOWEVER, I was playing around in Illustrator and came up with the following compromise that would tick some boxes for me. I would like to get feedback on the idea from experienced minds before moving forward with construction:

Pros
1. Isolated live room.
2. When not in use, the live room can be used as an additional storage space; mic stands, cables, instruments etc. would otherwise take up space.
3. Save money on studio time for certain isolated tracks.

Cons
1. Splitting an already small room in any way will compromise the acoustics of both spaces (1 small room vs 2 even smaller rooms).
2. The live room is really small, how usable could it be really?
3. The live room door (transparent sliding door) is exactly where a first reflections absorber should be.

First question:
For me, the Pro number 1 is the strongest draw, so I guess what I’m asking is: If I were to split the room in this way, the live room would be tiny: in your experience, could I even get usable recordings out of it? For reference, I primarily expect to record vocalists and acoustic/electric guitarists here.

[gullfo]

i wouldn't call it a live room - but as a vocal booth it could work

[Soundman2020]

Hi there rominronin, and welcome to the forum!

I agree with what Glenn said, absolutely. Too small to use as a live room, but workable for a vocal booth, or amp booth.

That said, I'm not convinced that it would be a good idea. You mentioned that your building internal dimensions are: "Width: 400cm
Length: 430cm". That's a total of 17.2 m2 footprint for the building, without considering any isolation wall thickness. There's a couple of "specifications" commonly quoted for control room acoustics, and they all suggest a minimum floor area of 20m2 for stereo rooms (larger for multi-channel). That doesn't mean that you cannot possibly use a smaller room: it just means that anything smaller is going to have certain compromises, and is going to be harder to treat to get it usable. The smaller it is, the more treatment it will need, and the tougher it will be to get it working. At 17m2, you are already into "not so easy" territory, but still do-able. Going smaller doesn't seem like a good option, to me.

I'm not sure what the final interior footprint of the CR would be with your plan, but I have a feeling that it is going to be very small acoustically, and very cramped in practical terms. I'm thinking that a single room would be a better option.

There's also the issue of how useful that vocal booth would be: Being so small, it would have to be treated very much on the dead side, which is fine for vocals, but not so fine for many instruments: Given the size, drums are out of the question, for example, and even a large keyboard might have trouble fitting in. Ditto for an electric guitarist with a bunch of peddles, amps and speakers, or a bass player with his gear, if he likes to move around a lot. On the classical side, there's no hope for getting a piano in there, and strings would not sound good in there either.

So, if your work mostly involves just tracking vocals, and maybe acoustic guitar, and you don't mind a cramped, non-optimal (acoustically) control room, then your plan might be a good option. But if you were hoping to record the above instruments (or other similar things), or you wanted to record an entire band at once, or if you need high quality acoustic response in your CR for producing mixes that translate well, then I'm thinking that a single room would be a better option.

Which brings us to another point! A single room to be used for both tracking and mixing has drawbacks of its own, with the biggest issue being that the acoustic response required for a CR is rather different from the acoustic response needed for most instruments. So you would probably have to treat the room to be good for just one of those and suffer the consequences for the other, or go with variable (adjustable) acoustic devices, like this: What is variable acoustics? How do I do that? Some people think that they can sort of make the room response part way in between "good for tracking and "good for mixing", but the real result is a room that is good for neither, and lousy for both! Your real options are: make it good for one or the other, and live with that, or make it variable, which is moe complicated and more expensive, but can make a small room good for a range of uses.

1. Splitting an already small room in any way will compromise the acoustics of both spaces (1 small room vs 2 even smaller rooms).

Yep! Agree!

2. The live room is really small, how usable could it be really?

Yep! Agree!

3. The live room door (transparent sliding door) is exactly where a first reflections absorber should be.

This is not a deal-killer, as there are ways for dealing with that, but frankly it is the least of your worries. The other two are much more important.

My suggestion would be to figure out if you can make a single room work: You can successfully track many types of instruments in the CR, as long as there is enough space and the acoustic response is good enough for the musicians to play happily, and for the mics to pick up good sound: There are drawbacks (such as high sound levels, not being able to hear through your speakers what the mic is hearing, etc.), so it's up to you to decide if those issues are deal-breakers, or if you can live with them!

in your experience, could I even get usable recordings out of it? For reference, I primarily expect to record vocalists and acoustic/electric guitarists here.

Borderline: here's an idea. Get out a roll of masking tape, and tape out that exact shape and size of area on your living room floor. Put a chair in it, and a mic stand, and a music stand, and an amp, and some peddles, and see how you feel about that being a viable and pleasant space for a musician to play and track in. Allow for space to maneuver around the stuff, so you can get into the room, plug things in, sit down, and move around comfortably. That should give you a good idea of feasibility of using that as a booth. Personally, I think it would be very tight, but try it for yourself.

- Stuart -

[Starlight]

Source of the postI’m a Londoner who moved to Austria ...

Hello from another Brit. I live next door to you, country wise, in Slovakia.

Source of the postWidth: 400cm
Length: 430cm
One room, not two right? …Right?
I work with musicians and singer/songwriters, and I always wanted the flexibility that an isolated live room provides during the recording process.

I agree with Glenn and Stuart - after all, they are the professionals and I am not - that the whole plan looks very cramped for splitting up into 3 small rooms. However, where there is a will there is a way and just maybe you are prepared to live with the shortcomings if a suitable plan can be drawn up to make it work for you. After all, it's your studio.

Source of the postPros
1. Isolated live room.
Cons
3. The live room door (transparent sliding door) is exactly where a first reflections absorber should be.
First question:
For me, the Pro number 1 is the strongest draw ...

If all that means more than the restrictions such a small room makes, you could put the door further back so that it is behind the first reflection point. It can connect to the storage space (which doesn't look as though it has any way to access it) and a door from the store room gets you into the iso booth.

If you get to Poprad before I next get to Vienna, you would be welcome for a cup of tea and some brainstorming regarding your studio.

[garethmetcalf]

Hey Baris
It’s great to see you on here - I think you’ll get some excellent advice on your design. Stuart’s proposal to tape out the area in a room in your house is a great one. Good luck!

Cheers
Gareth

[rominronin]

Thank you for the replies so far.

Source of the post i wouldn't call it a live room - but as a vocal booth it could work

Totally; 'vocal booth' describes it far better.

...where there is a will there is a way and just maybe you are prepared to live with the shortcomings if a suitable plan can be drawn up to make it work for you. After all, it's your studio.

Hi Starlight, thanks man, I need to hear stuff like this too

If you get to Poprad before I next get to Vienna, you would be welcome for a cup of tea and some brainstorming regarding your studio.

I'll keep this in mind - I'm in St. Pölten, so let me know if you're ever in the area!

Source of the post Hi there rominronin, and welcome to the forum!

Hi Stuart, lots of great feedback so far - really glad I came. I tried your suggestion of marking out the dimensions on the floor to get a feel for the space. It definitely helps to get a physical idea of what we're talking about.

One room wins!

In the end, decided not to spit the room. Without going into too much detail, I would prefer to have a single mixing/listening environment of higher quality than two sub-optimal rooms. I am happy to utilise variable acoustic absorbers (so I can liven it up when recording, if necessary).

Now, on to the next round of details and questions…

Infinite, but lop-sided baffle

I’d like to flush mount my mains. This is the first time I will be flush mounting any speakers. I read the soffit/flush mount rules thread and homed in on the following design:

This is as close to the above guidelines as I could get it. It’s worth stating that I want to raise the monitors up so they’re above the desktop near fields (angled downwards, unlike the in image). I tried this arrangement in my current room and it sounds great - the sound should be even better when flush-mounted.

The only thing that looks weird to me is how close the speakers are to the inside edge of the baffle. Is this a problem do you think?

On a more practical note, the baffle structure takes up a lot of volume. I had considered a 25% angle instead - to minimise that - but that pushes the listening position back, close to the room centre. So I decided to keep it where it is.

Is this design ok, or am I missing something obvious here?

Floors and walls

The walls are structural clay tile - they are 25 cm thick. 2 of the 4 vertical walls are external walls which will be finished with a polystyrene facade of 20cm. The facade on the North wall (where the speakers will be) is already completed, the West wall (where the door is) is not yet done (local material shortages due to covid).

The East and South walls are adjacent to existing buildings. On the East side is our neighbour’s tool shed and the south side is the bathroom and bedroom of our house.

I tend to mix at low volumes for long stretches (around 60 dB), so I’m not too concerned about noise escaping outwards. Our house is constructed with the same material, and even now, without the insulation of a polystyrene facade, external noise is blocked considerably well.

Ceiling

Given the above, the weak link is clearly the ceiling. Currently, there is rock wool between the rafters, which is held in place by a moisture absorption/distribution sheet (the product is called Hygrodiode). Here’s what it looks like:

The ceiling needs plasterboard at least, right? The local hardware stores all have a system that looks complex (and expensive) involving C channels all the way round and a grid of perpendicular framing supported from the rafters. Here's a shot of what I'm talking about:

I’d like to avoid using this if possible. Someone (with more construction experience than I) recommended resilient channel across the rafters, onto which the plasterboards could be screwed. This sounds like a far simpler (and cheaper solution), but I can’t find resilient channel in Austria (anyone know what it’s called in German? Maybe I’m missing the right terminology).

So here are my questions:
1. Can’t I just screw the plasterboard directly into the wooden rafters?
2. If not, and if resilient channel is not available, then how about fixing wooden beads to the rafters and securing the plasterboard onto those?
3. Another alternative is to do nothing and see what it sounds like when the door is installed. If it’s REALLY noisy, then perhaps I need a room in a room anyway.

What are your thoughts on this?

PS. Hi Gareth!

[gullfo]

like all good answers, it depends.

on the ceiling - do you need the ceiling decoupled? if not, then attaching the gwb to the rafters/joists will suffice. if yo udo need to decouple, resilient channel would not be the way to go, but rather at a minimum, isolation clips on the rafters and hat channel (although the isolation clips and C channel are the same idea) with the gwb on the hat channel. often good to use a layer of plywood on the hat channel first, this makes attaching multiple layers of gwb easier and also something to later use for ceiling treatment attachment.

on the speakers - are you experienced with soffit mounted speaker systems in terms of monitoring your mixing? if the speakers are stands meets your needs, then why not stay with that? if soffit is still the way to go, then consider the speaker arrangement - firing the HF drivers into the nearfields might not be desirable so maybe placing the larger mounted speakers a bit wider would be good. also provides room for expansion of the video monitor, desk, etc over time, as ripping down the front wall to rebuild it is tedious at best.

there are a couple of approaches to the height - one is straight vertical walls and invert the speakers - HF driver down, LF up to get the acoustic center of the speaker as close to optimal as possible. or angle the walls vertically about 8-10° to aim the acoustic center to your listening position. the latter requires more precision in the build since you now have two angles to address in 3D.

in either case, building the wall requires that it is also very solid so vibrations are damped and residual resonances are pushed higher to further enable damping.

[rominronin]

Source of the post on the ceiling - do you need the ceiling decoupled? if not, then attaching the gwb to the rafters/joists will suffice.

I don’t *think* I need it decoupled - this approach takes up the least a mount of valuable space from the room. Do I need to worry about things like the rafters warping or the plasterboard cracking?

Source of the post on the speakers - are you experienced with soffit mounted speaker systems in terms of monitoring your mixing? if the speakers are stands meets your needs, then why not stay with that?

I could stick with stands, but my only experienced soffit mounted speakers in a pro studio impressed me enough that I’ve wanted them since. Aside from the sound, I think a studio space looks and feels much better when you have that as a feature too.

Source of the post maybe placing the larger mounted speakers a bit wider would be good. also provides room for expansion of the video monitor, desk, etc over time, as ripping down the front wall to rebuild it is tedious at best.

My concern with flush mounting them wider is that it would push the listening position backwards, very close to the room center. I could place them so wide that the sound converges beyond the room center, but then my mixing position would be compromised. Do you see an issue with the suggested layout then?

Source of the post there are a couple of approaches to the height - one is straight vertical walls and invert the speakers - HF driver down, LF up to get the acoustic center of the speaker as close to optimal as possible. or angle the walls vertically about 8-10° to aim the acoustic center to your listening position. the latter requires more precision in the build since you now have two angles to address in 3D.

in either case, building the wall requires that it is also very solid so vibrations are damped and residual resonances are pushed higher to further enable damping.

Yep!

[gullfo]

i asked about mounted vs stands because i'd say 70% of my clients want soffits, and about 30% want to stick with stands because that's what they're comfortable with.

in the wider spread - contemplate refractions from the desk and speakers on stands as well as simply enabling a wider sweet spot. most folks tend to mix on their nearfields and then move up to the soffit speakers for louder and LF testing of the mix (as well as hyping clients ). either ways its a balancing act as well as seeing the future and determining if a set of larger speakers (say ATC, JBL, Genelec, etc)

[Soundman2020]

I don’t *think* I need it decoupled - this approach takes up the least a mount of valuable space from the room. Do I need to worry about things like the rafters warping or the plasterboard cracking?

The reason you might need decoupling, is if you need improved isolation. If you are happy with the isolation you have at present, then you probably don't need to decouple. If you want more, then decoupling is an option, provided that you do the rest of the method to get a proper 2-leaf system, tuned low enough.

I could stick with stands, but my only experienced soffit mounted speakers in a pro studio impressed me enough that I’ve wanted them since. Aside from the sound, I think a studio space looks and feels much better when you have that as a feature too.

There is most definitely an acoustic advantage to flush mounting (soffit-mounting) your mains. It eliminates or reduces many of the artifacts associated with the speaker being inside the room, since technically, if it is flush mounted, it is not inside the room any more! But as Glenn mentioned, it needs a bit of skill to design and build the soffits correctly, as well as adding a bit of extra cost and complexity to your build. That said, I practically always recommend flush-mounting. It really is beneficial.

My concern with flush mounting them wider is that it would push the listening position backwards, very close to the room center.

It doesn't have to! You can change the angles of the soffits. It's something of a myth that the angle must be exactly 30.000000°! Nothing bad will happen if you make it 31° or 29°. Not even if you make it 35° or 25°. As long as you understand what the consequences are, and design things suitably, you can vary the angle quite a bit. John Sayers once built a very successful room with the speakers angled at 45°! Personally, I try to not go outside the range 25° - 35°, but it is possible if you work carefully.

So, spreading your speakers further apart is a real option, and as Glenn mentioned, it would be worthwhile in your case. I agree.

You might find this article useful, that I wrote a while back, about speaker angles: Speaker setup, and the equilateral triangle

I could place them so wide that the sound converges beyond the room center, but then my mixing position would be compromised.

Actual, you DO want the sound fields from your speakers to meet closer to the room center! This does not compromise your mix position. In fact, it improves it. You do NOT want the sound fields meeting in the middle of your head. Bad idea. take a look at the above article to get a better handle on this. Ideally, the two axes (plural of "axis", not a tree-chopping tool!) from your speakers should meet several inches behind your head, in order for the speakers to be optimally aligned with your ears. In that article, I give an experiment you can try to convince yourself that this is the right way to set up speakers.

- Stuart -

[rominronin]

Summary
It’s been a while, here’s a short list of updates:
- The studio is now functional!
- the ceiling has been sealed with plasterboard - no special isolation.
- the floor has been laid down
- a cheap, temporary door has been fitted
- the electrics have been wired

The whole thing was a DIY job, apart from that last point - that’s a job for professionals. Needless to say I feel very proud of my handiwork.

But that’s not why I’m here. The reason for that is some additional feedback from you wonderful people.

Speakers, soffit mounting (infinite baffle)
My main monitors are on stands in the positions of the planned soffit mounted speakers. I'm basically very happy with the way they sound in the room. I was of two minds about soffit mounting them, but the room already sounds so good that I don't want to change anything unnecessarily.

Storage
I currently have a really good balance between useful space and storage. this for me is very important since the space is small and has to meet so many needs, while not being a complete mess.

I gave up my nice big swivel chair in favour of smaller seats that we got from a relative. They are also comfortable, but they do not consume quite so much volume in the room.

Isolation
I've been using the space in my free time in the last few months, very rarely does the external noise get so loud that I cannot use the space. I was hoping for this, since the space is tight, and I don't want to lose more volume by constructing a room in a room. Of course, it is always an option for the future.

The door
I really just bought the cheapest door I could find and mounted it. I cannot afford a proper external door right now, and I don't want to construct one either.

The REW measurements
I took some measurements after following several guides on calibrating the system. I am no expert at interpreting the graphs yet, but at the volumes I listen at, the room is already smooth. There are basically two peaks in the low end that are so low that I'm not sure if I want or need to treat them. I would love a second opinion on the measurements, but before I post them, I want to ask if there is a certain guide for sharing measurement screenshots (or REW files).

Pictures
Here are some before and after shots. I created a more detailed build log of nearly 40 images, which you can see over at imgur.

Front:

Back:

[gullfo]

nicely done!

[eightamrock]

This looks really nicely done, and you were able to make all the right compromises!

Great space. Congrats.