Is there a magic size?

[elastic]

Hi all,

Been reading many things on here and learning, plus the Rod Gervais book 'build it like the pros'.

Basically i have about a 10m x 11m plot of land at the bottom of my garden and i plan on building my own studio (1 room, no need for mic's, live rooms or anything, i make Techno, so just drum machines and synths to record in)

I plan on making the studio about 5mx3m internal size.

My questions is, im worried about the interior size - can i just pick my size and get on with it? Or are there dimensions to be avoided?

It's really freaking me out.

Any help or advice would me gratefully appreciated.

Thanks

[Soundman2020]

My questions is, im worried about the interior size - can i just pick my size and get on with it? Or are there dimensions to be avoided?

Magic size for what? Are you planning to record and mix in there, or just do some jamming?

For mixing, the recommended minimum size is 20m2 (about 215 ft2). That doesn't mean that anything smaller is terrible: it just means that it's harder to make it workable. The smaller you go, the more treatment you'll need, and the harder it gets.

That's for mixing. For jamming / rehearsing / tracking, the room really should be bigger than that if you want to get a good sound out of acoustic instruments. Instruments "like" large rooms with high ceilings. That's where they always sound best. Small rooms sound "small", both in person and also with recorded tracks. If you only ever plan to close-mic everything and add ambiance electronically, then that's one option, but if you want natural room sound in your mixes, then small rooms are not good for that.

A few years ago, Sound on Sound magazine did some tests in several major studios, taking he exact same drum kit, drummer, mics, gear, and everything from place to place, setting them up in the live room, and recording the exact same song played the exact same way. Not surprisingly, the larger rooms sounded better. And those were all high-end pro recording studios, well treated.

So basically: for mixing/mastering, go with around 20m2 floor area. For tracking/rehearsing, go with "as big as you can possibly make it".

are there dimensions to be avoided?

Not specific dimensions, no, but the relationship between dimensions can be an issue. Thus, your length, width, and height should NOT be the same as each other, nor within about 5% of being the same. And the room should not be more than about 3 times longer than it is wide or high. There are other rules-of-thumb, but once again, it depends on the purpose of the room: one set of rules for control rooms (mixing/master), another set for live rooms (rehearsal/jamming/tracking).

- Stuart -

[elastic]

Thanks! It will be a room for jamming and mixing.

Note - Not jamming with mic'd instruments like guitars or drums - i'm working with drum machines and synths which will be recorded into the computer via a mixing desk, so the room sound is not important in that respect, but for mixing its still important obviously.

I make electronic music, techno.

I was more concerned about getting the room dimensions wrong incase i end up with these room nodes or something thats unwelcome.

[Soundman2020]

but for mixing its still important obviously.

For the electronic stuff, there's no problem then. But for mixing there sure is. Use one of these Room Ratio calculators to figure out the best dimensions for your room:

http://www.bobgolds.com/Mode/RoomModes.htm

OR

http://amroc.andymel.eu/
https://amcoustics.com/tools/amroc

Both of those are very good, and will help you to decide how best to build your room. They give you tons of information that is really useful to help figure out the best dimensions.

But basically, you should worry about maximizing the room volume. That's the first priority. Largest possible amount of air inside. Then if the calculators show that the ratio is terrible, adjust a little bit. But don't go crazy over ratios.

If you want to understand all of the aspects that you should be considering when designing your room, then google a document called "ITU BS.1116-3", download it, and look at chapters 7 and 8 (the other chapters are not relevant to what you are doing, so you can skip them). That lays out what you need acoustically for a "critical listening room", and that's what a control room is.

If you can, make your studio a little larger, so you can get about 20m2 of floor area. That's the final floor area, after the isolation walls are in place.

You should also consider height: Try to get at least 2.5m, and here too, more is better: if you can 3m, that's fantastic.

- Stuart -

[elastic]

Thanks Stuart, really appreciate this advice.

Had a look at bob golds calculator but have no idea how to use the data it came back with

I'll see if i can get 5m x 4m interior, i forget now what the height allows here in the UK.

Will report back soon to this thread with pics and info

[elastic]

Then if the calculators show that the ratio is terrible, adjust a little bit.

I like the amroc site, i put my 5mx4m x 2m height data in and got the results back, but what would terrible ratios be?

Also, would 5x4m be considered too close to being square, would i be better off going for 6mx4m or 5mx3m for example so its more of a rectangle?

Thanks

[Waka]

Then if the calculators show that the ratio is terrible, adjust a little bit.

I like the amroc site, i put my 5mx4m x 2m height data in and got the results back, but what would terrible ratios be?

Also, would 5x4m be considered too close to being square, would i be better off going for 6mx4m or 5mx3m for example so its more of a rectangle?

Thanks

Hi elastic,

The bob gold calculator has 3 tests that the room ratio is tested against. They're a good pointer as to whether your room dimensions will be a good starting point. (BTW 6m x 4m x 2.4m passes all 3 tests).

As regards to your suggested dimensions :

If you can afford 6m x 4m then go for that over 5m x 4m. The additional 9-10m3 of volume is worth it being pushed a little out of the bolt area (another guide to whether room dimensions are good). You will have a greater distance behind your head at the mix position, which will just about be enough to avoid reflections within 20ms (pretty much required for good mixing) and therefore greatly simplifying the rear wall treatment design.

Dan

[elastic]

Ah that’s great advice thanks Dan. Much appreciated.

Yes I was struggling to read the results of those sites due to my lack of knowledge. Makes sense about what you say though with regards to a more lengthier room.

What would be a desired wall construction and thickness?

I was thinking of using Sips panels (the acoustic type) then a stud wall inside. I think it was Rod Geiger who suggested a 2 leaf system?

Once I know my wall thickness I can get to laying the concrete base down.

[elastic]

Ok so been doing lots of learning and reading and mocking up sizes on site.

I’d be comfortable doing -

Width - 5.5-6m
Length 3m or 3.5
Height 2.5m

I like the idea of using sepmeyers ratio to scale it to my size. I used this link to work test some sizes according to his ratio -

http://www.odometer.org/misc/ht/

I presume the thing to keep in mind when using his ratio is, even though it can be scaled down to small sizes, they would not be ideal.
Best to use his ratio and try and get the biggest room that fits my budget and area I have to work with.

[Waka]

Remember at such sizes the ratio is not the most important part. You say 5.5-6m length and 3-3.5m width, if you can fit 6m x 3.5m x 2.5m and can afford it then do that, regardless of the ratio. If you can push to 3.6m width you'll even pass the 3 bbc tests.

Just think pure volume at first. What can you fit and what can you budget. If you can budget for 2.8m height then do it, if you can budget for 4m width then do it. Put your biggest volume into the Bob golds calc, and adjust that slightly to pass the tests and get near the bolt area.

Dan

[elastic]

Thanks Dan, appreciate that. Will keep planning.

Something I’m struggling with is working out what level of isolation I require in the walls, so I can then figure out how thick the walls will be so I can the work out the size I can build.

[Waka]

With regards to isolation you need to know what you dB you produce first, then minus what you need it to be outside.

For example:
If you make techno music at 80dB, you need that to be down to 34dB at the closest neighbours boundary. (It could be legally you're allowed more than 34dB, it depends where you are. Basically measure the ambient noise on a quiet evening, if it's above 24dB (it will be) then add 10dB to that for the legal limit in your area).

So you would be looking at 46dB of isolation needed if you worked at 80dB. You can take 6dB off that for each doubling of distance to your room.
For example:
Neighbour's boundary is 1m from the closest studio wall, take away nothing.
Boundary is 2m away, you can take off 6dB.
Boundary is 4m away, take off 12 dB.
And so on.

This gives you your legal isolation requirements. You would definitely want to be have a bit more than this though just in case.

Dan

[DanDan]

Most of the work in the textbooks on Room Ratios is old and not about ours sized Rooms but Concert Halls.
The Ratios do not scale. Repeat they do not scale. Check out Cox's work on more robust ratios and ones suited to small rooms.
Then consider my good friend boggy's comment that there are no modes in his treated rooms......
Also plasterboard does not support the lowest modes anywhere near how concrete does, and these ratios are generally presuming a very massive hard boundary.
Soundproofing is difficult to achieve, particularly at LF. I suggest playing typical trax at typical volumes, then go forth and listen with a Sound Level Meter in hand.
C or Z Weighting for the SLM to hear the bass.
DD

[Soundman2020]

Then consider my good friend boggy's comment that there are no modes in his treated rooms......

I would beg to differ! There are ALWAYS modes. The simple fact of having walls, floor and ceiling creates the modes. The treatment might well damp them into oblivion, but they are still there, and still shape the overall frequency response.

From that point of view (treating modes into oblivion), here's a couple of rooms with "no modes":

http://www.johnlsayers.com/phpBB2/viewt ... =2&t=20471

http://www.johnlsayers.com/phpBB2/viewtopic.php?t=21539

... and built very simply, too...


The only way to have a room that really does have no modes, is to use a bulldozer... Flatten the entire building, so there's nothing around but empty air, and you do indeed have no modes...

- Stuart -

[DanDan]

Of course modes are usually detectable in inadequately treated rooms. But how significant relatively? Everything Acoustic is relative and spectrum dependent.
Boggy's have typically four feet of absorption on opposing walls. Newell much more. I wouldn't hazard a guess as to what level of mode is 'significant' but IMO a holistic view is preferable to focussing on just one aspect, which may well not be at all the most powerful one at play.
http://forums.musicplayer.com/ubbthread ... ven_matter

As Cox and others have pointed out the old optimal ratios do not scale to small listening rooms. http://www.acoustics.salford.ac.uk/acou ... nt=methods
I would always add that sound travels slower in fibre so the visible dimensions of the boundary room are quite different from the finished treated acoustic dimensions. Very different in a deeply treated room.
I reckon most of us will agree that bigger is generally better, particularly as it can include treatment. IMO the Back Wall is typically the biggest factor at play, and most often inadequately treated.
The second biggest factor is see is the almost absurd practice of placing the listener Mid Width AND Mid Height.

DD