Looking for some opinions/problems on my studio design

Hello to you all, Im Bruno, from Portugal, Europe, and I am developing a studio for some live music rehearsal and some recordings. Am an architect, but im not an expert on acoustic insulation, so i need some reviews os my plans. The measurements are in meters. The free height space is 11.6 ft. The inside height of the rooms goes from 8.5 ft in the lower corners, and 9.5 ft at the center of the rooms, making a gable roof. The studio is being planned for a rented space, so im trying to avoid the concrete block walls. I'm aiming for a solution of a double 5/8″ drywall on either side of a duble 2x4 wood stud wall with Rockwool 70kg, 4 inch insulation "inside" the wood studs, and 2 loads of Green Glue on both sides. I have a big doubts... this type of construction is enough to completely isolate the sound between the live rooms? What kind of problems can you guys find at my design? Thank you.

Hi Bruno, and welcome to the forum! :) I would say the biggest issue I see with that design is the shape and layout of the control room: Basically, it is all backwards! The control room should never get narrower towards the back like that. It could get wider, for sure, or stay the same width, but narrowing it down is a bad idea, for many acoustical reasons. I would give serious thought to correcting that, as it is a major issue. I can't see that working as a control room.

I'm aiming for a solution of a double 5/8″ drywall on either side of a duble 2x4 wood stud wall with Rockwool 70kg, 4 inch insulation "inside" the wood studs, and 2 loads of Green Glue on both sides.

It's hard to see from your drawings, but it looks like you have the isolation mostly correct, except there seem to be some areas where there are issues with continuity of the leaves. But the basic plan is correct: two leaves, two layers of 16mm drywall for each leaf, double studs, GG, and sealing.

I have a big doubts... this type of construction is enough to completely isolate the sound between the live rooms?

that depends on what you mean by "completely isolate"! :) There is no such thing as totally soundproof: any sufficiently loud noise can penetrate any conceivable man-made barrier. Even the best isolated studio in the world, with an amazing 100 dB of isolation, cannot isolate the sound of a shotgun blast. That's why we tend to speak in terms of "decibels of Transmission Loss", when it comes to isolation. There are many, many research papers on many different types of construction, and how much isolation each of them gives in true laboratory settings: What you are planning, if you build everything perfectly, should give you in the region of 60 dB of isolation, which is considered pretty good for a studio, and about as much as you can expect on a reasonable budget in a typical building. But it's a long way from "completely isolated", if you mean "all instruments totally inaudible". So is it "enough"? Only you can answer that question. Vocals will most likely be inaudible between rooms, even very loud vocals. Must instruments will be inaudible or greatly muffled, except for ones with a lot of low frequency energy, or ones that are very loud to start with. Drums, bass guitars, loud keyboards, for example, will probably be audible, albeit very muffled. Drums, for example, usually come in at around 110 to 115 dB, when played reasonably hard, so in the control room you would hear those at around 50 dB, which is a bit quieter than normal speech, and it would be mostly the low frequency "thump" that you would here, not the cymbals or hi-hat. Is that acceptable? For the vast majority of studios, it is, but only you can judge if that is acceptable for YOUR studio. It would be good for you to measure how loud it will be in their, by measuring (with a sound level meter) the level of a typical recording session that you do today, in whatever place you are doing that. That number is part of the equation that you need to calculate. Now, while the band is still playing inside, walk away, out of the room, down the hall, outside if necessary, until you think the level you are hearing is "acceptable", and note down the level you are seeing on the meter. That's the other number that you need. Subtract that one from the first one, and you have answered the question: "How much isolation do you need?". Let us know what that number is, and we can help you choose an isolation plan that will give you that number. But most of all, first concentrate on getting a decent, usable shape for your control room, following the normal guidelines for that. - Stuart -

Thank you. Basically, the control room is a result of the other 3 live rooms, but I'm going to correct that. I've done some calculations on how much db isolation I am aiming.... it's around 70. I know that this kind of wall have an STC of 63, but I'm trying to get to a solution that improves that number a little bit. I'm aiming for this because I have a lot of friends playing on heavy metal bands, and they are going to be the main users of the rooms... so they are a bit loud!! :twisted: Can you tell me the problem areas that you have identified in the continuity of the leaves? Other question.... it's better to be built on the concrete slab, or, built the rooms in a floating wood structure?

I've done some modifications. The recording room is more like a small theater with a low ceiling above the control table and a much higher ceiling in the wall behind the sofa.

I've done a sectional drawing, through the recording room and the live room 3.

Is the control room still with big problems in terms of acoustic and general shape?? What do you think of the constructive method of the rooms? Do you think I will need to raise the floor? If yes, is it better to fill it with sand or rock wool?

I've done some modifications.

That's much better, but the control room still get narrower at the rear.

Is the control room still with big problems in terms of acoustic and general shape??

It has improved, but it still could be better.

What do you think of the constructive method of the rooms?

Your isolation walls are coupled. That should be changed. Each room should consist of a single leaf that stands alone, all by itself, not connected to any other room. No mechanical connections at all.

Do you think I will need to raise the floor? If yes, is it better to fill it with sand or rock wool?

This will answer your questions for you: viewtopic.php?f=2&t=8173 - Stuart -

The figure that you post indicates that you have triple leaf exterior walls around live rooms 1,2 and 3 and it is not good for low freqency isolation and for wallet also:) Also storage walls could be done better, to save some space, money and give actually the same isolation. Maybe storage rooms between LR1 and LR3 could be one big storage room? -Mathew-