I am in the process of soundproofing a garage to make a listening room. I am interested in ventilating the room and think that a baffle system for an air vent might be the best way to go. Does anyone have any advice about this or can point me at any useful information on the subject? My current thoughts are to a box with inlet and outlet which would be lined with acoustic foam and have partial shelves on alternate sides (also covered with acoustic absorbing foam). Any ideas would be appreciated!
Most solutions I have seen make the air turn a couple 90 degree angles and line that portion of the tubing with an acoustical liner. As an example, our new building at the college I teach at has the return air vents coming into the room from a wall but taking the air in from the top of vent, by the ceiling. That cuts down on noise transmitted into the vent that could get to another room. The supply vents then come in through walls, but the vents are on the bottom of the ducts, towards the floor. You will need to look at both the supply and return vents and it may be more effective if you also make changes to vents close to the garage in other rooms.
Building something yourself is most rewarding, but in this case I’d revert to sound insulating flexible tubes specially designed for this. They are quite cheap and tested for ventilation regulations, you could use some of them in series in an enclosure that is pretty much a box with inlet and outlet. No need for complicated work. You probably need two, an inlet and an outlet. Combine the whole with a heat exchanger and your system is not only soundproof but environment friendly too.
Hi,
In my country ( France) the kind of box you describe are forbiden: the acoustic foam makes a great place ( substrate) for nasty things to grow on and rise a potential health hazard ( for intake).
Like Markbakk told, go looking for dedicated stuff.
I must say it is not clear to me what Deloaper is asking for. Could you describe what you have done/plan as soundproofing?
In a way it will define your needs for ventilation: a floating structure ( box into a box) will ask for more noise insulation from ventilation than a simpler approach ( the background noise level will dictate the noise floor).
Some thoughts about it: soundproofing a room require ventilation mandatory. Best even hvac and ventilation but prices goes up quickly in that case.
The location of intakes and outakes will differ with room requirement ( and shape and room plan...as well as global built limitations). If you have a sketch it could help to define where to locate them.
As Stv pointed there is some silencers existing ( most often to lower noise from fan within a duct- inline fans), dedicated ducts ( 'soundproofed' for fans, same as the silencers) some 'sockets' ducts ( if you build a floating structure you need low structure born transmission and the sockets display it),...
Abit of strategy in location of components could help too.
In a way it will define your needs for ventilation: a floating structure ( box into a box) will ask for more noise insulation from ventilation than a simpler approach ( the background noise level will dictate the noise floor).
Some thoughts about it: soundproofing a room require ventilation mandatory. Best even hvac and ventilation but prices goes up quickly in that case.
The location of intakes and outakes will differ with room requirement ( and shape and room plan...as well as global built limitations). If you have a sketch it could help to define where to locate them.
As Stv pointed there is some silencers existing ( most often to lower noise from fan within a duct- inline fans), dedicated ducts ( 'soundproofed' for fans, same as the silencers) some 'sockets' ducts ( if you build a floating structure you need low structure born transmission and the sockets display it),...
Abit of strategy in location of components could help too.
I am in the process of building a room within a room. It will have windows and a double door but so far I have not found a good ventilation system, there will be no air conditioning.
Dedicated duct liner is typical here, a fibrous pad with an acoustically transparent sealed top coat.
https://www.jm.com/en/hvac/duct-liner/
Your best bet would be to install a ductless system dedicated to that room. That removes the necessity for ducts completely for A/C and heat.
Yes as wide the duct as possible ( 20cm diameter is a minimum), oversized fan with regulator to keep speed low: less noise.
Floating room: if done 'right' this is the best approach for soundproofing.
Floating room: if done 'right' this is the best approach for soundproofing.
If there is filtering ( for particle, dust, etc, etc,...) they must be an easy access to clean regularly and they should be located first in the row ( if there is multiple stage or other 'modules' ( silencers).
There is a need for an one way 'flap' damper on output ( exhaust) especially if you have no filtering device ( it stop dust from being bring into the room in case wind direction blow into exhaust duct). It can help in case of fire too ( if ventilation is shut down of course!).
Which lead to the need to have either the fan variator accessible right next the door or a global shut off for main (electricity) when you leave the room ( it is better for the planet and in case of fire you don't have a continous flow of oxygen to keep fire alive).
And while at it, it might be very practical to have a dedicated (to the room) electrical distribution panel too. You will be happy to not have your fridge to polute your main with click and pop when it start.
What about something like an absorbtion silencer on a car exhaust - have a ( 6 inch? ) perforated tube passing through a box.
I had thought of using a similar idea for a speaker enclosure, using a driver at one end of a perforated tube inside the main enclosure.
Car silencers have been developed for many years, that's where I'd look for inspiration. A " Brooklands " vent with fishtail?
I had thought of using a similar idea for a speaker enclosure, using a driver at one end of a perforated tube inside the main enclosure.
Car silencers have been developed for many years, that's where I'd look for inspiration. A " Brooklands " vent with fishtail?
Whatever you do, make it oversize/overspec'd. I once built a false wall for a studio which included 2 large baffles, one for intake, one for air out. I always had the feeling there wasn't quite enough air getting into that basement!
The problem you face isn't the air noise of cooling or heating. Thats the easy part. The real challenge is low-frequency sound leakage in and out. Many studios use a split unit heat pump setup that recirculates most of the trapped air, just cooling or heating it and having a small controlled air leak to infuse and exchange fresh air slowly. It's often introduced with a TL style baffled air handler that can be closed or opened remotely. The rest of the studio is usually equipped with air tighr pneumatic seals in the doors or often double door with the control room in between.
Of course you would hermetically seal the room then run either surface supply with a return or a rebreather….
The broadcast studios I inherited and built over decades dealt with these issues by using lined ducts employing one or more 90 degree bends and careful placement of returns to avoid nearby openings in the return plenum. Improper window and wall construction was far and away the greater contributor to low frequency cross talk between rooms. If the videos are accurate PS Audio's new Octave Studios may display a fine example of the former. They made a design change during construction adding a window to a double stud wall between two sound rooms. The internal window sill showed no sign of being split, essentially hard coupling the two separated walls together and rendering their isolation moot. What appears to have been retroactively blowing 4" cabling holes through the wall couldn't have helped either.
'Hermetically sealed' rooms likely contravene reams of workplace safety standards.
'Hermetically sealed' rooms likely contravene reams of workplace safety standards.