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Help with placing acoustic treatment in my home studio (with dimensions and photos)
Old 4 weeks ago
  #1
Here for the gear
Help with placing acoustic treatment in my home studio (with dimensions and photos)

Hello. I have recently bought some professionally made acoustic treatment. 4 bass traps 120x60x17cm and 4 panels at 120x60x9cm (all seen in photos). The room is a little oblong and the door is in one of the corners (please see photos) 3.5m x 3.15 is rough dimentions.

My plan was to place 3 of the bass traps in the available corners (as seen in the photos) but raise them somehow so that they are halfway between the floor and the ceiling and then apply the 4 acoustic panels around the room in reflection areas, Im not sure what to do with the 4th bass trap. The person i bought them off had 2 bass traps stacked on top of each other reaching floor to ceiling but my room is not tall enough to do that.

I don't have much space and my monitors are literally a few inches from the back bass traps (as seen in photos), i was considering taking the monitors off the stands and placing them on my desk to save some space?

The room is not actually a bad sounding room and i've recorded and mixed in here a lot over the last 12 months with the help of sonarworks. I will say though that since just placing the panels inside the room it has become very dry already. Any tips on all of this would be greatly appreciated. I thought by showing photos and dimensions that it would give a better idea of what i am dealing with. Thank you for reading
Attached Thumbnails
Help with placing acoustic treatment in my home studio (with dimensions and photos)-img_0453.jpg   Help with placing acoustic treatment in my home studio (with dimensions and photos)-img_0454.jpg   Help with placing acoustic treatment in my home studio (with dimensions and photos)-img_0455.jpg   Help with placing acoustic treatment in my home studio (with dimensions and photos)-rooms_33196574_studio-office.jpg   Help with placing acoustic treatment in my home studio (with dimensions and photos)-rooms_33196609_studio-office.jpg  

Help with placing acoustic treatment in my home studio (with dimensions and photos)-screen-shot-2019-08-31-10.24.05-am.png  
Old 4 weeks ago
  #2
Don't place your monitors on your desk as the desk will resonate and act as part of the speaker cabinet making it sound worse than on stands.

Unsure what you can do with the 4th bass trap - maybe you can use it as a free standing trap by the door when in the door closed. I've been recommended that acoustic treatment should be balanced so that both sides of the room are the same or as close as possible.

For the 4 other panels your most useful positions are going to be first reflection points - right, left and above the listening position so probably a pair above and 1 each side with your current panels.

I would also recommend getting more panels to compliment the existing ones so that you cover floor to ceiling in the corners.
Old 4 weeks ago
  #3
Lives for gear
 

Quote:
4 Bass Traps 120x60x17cm and 4 panels at 120x60x9cm (all seen in photos).
Those are not really bass traps. They are more like broad-band acoustic absorbers. 17cm thick is the bare minimum for a low-mid absorber. Real bass traps (the type needed for typical small rooms) are around 50-90 cm thick at the widest point, and maybe 20cm or so thick at the narrowest point. Search for "superchunk bass trap" to find out how you can build them yourself.

Those panels you have would work well on your first-reflection points.
Quote:
My plan was to place 3 of the Bass Traps in the available corners (as seen in the photos) but raise them somehow so that they are halfway between the floor and the ceiling
Room modes terminate in the room corners. The place where three surfaces meet is therefore the most effective location for bass traps. In other words, at the top of the wall (where the two walls meet the ceiling), and at the bottom of the wall (where the two walls meet the floor). If you place your bass traps half way up the wall then you are not maximizing the effectiveness. They should be up at the ceiling or down at the floor, but not in the middle.

The ones for your first reflection points go roughly half way up the wall: centered about 120cm above the floor, at ear height.

Quote:
I don't have much space and my monitors are literally a few inches from the back Bass Traps (as seen in photos), i was considering taking the monitors off the stands and placing them on my desk to save some space?
As mrfantasticsaid: never put your speakers on the desk, or a shelf! Very true. You are doing right by having them on stands behind the desk, very close to the front wall. That's the correct place for them. However, you should stand them up vertically, instead of having them laid on their side. I'm posting an image down below to show you why that is.

Also, your bass traps will be far more effective on the rear wall, not on the front wall as you have them now. Put them in the two rear corners. I would out two of them in the floor (like you have them at present), then the third one hung horizontally across the top of the rear wall, angled diagonally so it straddles that corner, just like the other two should straddle the wall-wall corners diagonally.


Quote:
The room is not actually a bad sounding room and i've recorded and mixed in here a lot over the last 12 months with the help of sonarworks. I will say though that since just placing the panels inside the room it has become very dry already.
You could use REW ( How to calibrate and use REW to test and tune your room acoustics ) to figure out what the issues are with the room, and help you decide how to treat it. REW is free, and very good at analyzing the acoustic response of your room. You can learn a lot about the room like that, then use that information to plan the treatment.


- Stuart -
Attached Thumbnails
Help with placing acoustic treatment in my home studio (with dimensions and photos)-speakers-mounted-vertically-horizontally-standing-up-laying-down-side-interference-patter.jpg  
Old 4 weeks ago
  #4
Here for the gear
Quote:
Originally Posted by mrfantastic View Post
Don't place your monitors on your desk as the desk will resonate and act as part of the speaker cabinet making it sound worse than on stands.

Unsure what you can do with the 4th bass trap - maybe you can use it as a free standing trap by the door when in the door closed. I've been recommended that acoustic treatment should be balanced so that both sides of the room are the same or as close as possible.

For the 4 other panels your most useful positions are going to be first reflection points - right, left and above the listening position so probably a pair above and 1 each side with your current panels.

I would also recommend getting more panels to compliment the existing ones so that you cover floor to ceiling in the corners.
Thank you for your thoughts. I will keep the speakers on stands but turn them vertical as the other guy said. I may put speaker stands behind desk and not actually to the full side of the desk. That will make some room too.

Thanks for considering the door at the back, i actually leave it open when mixing as i thought the sound could not build up if there was not a corner for it to build in. That being said i understand now from what you have said that the room needs to be as symmetrical as possible.

The ceiling placement may not be doable as i live in a rented space.
Old 4 weeks ago
  #5
Here for the gear
Quote:
Originally Posted by Soundman2020 View Post
Those are not really bass traps. They are more like broad-band acoustic absorbers. 17cm thick is the bare minimum for a low-mid absorber. Real bass traps (the type needed for typical small rooms) are around 50-90 cm thick at the widest point, and maybe 20cm or so thick at the narrowest point. Search for "superchunk bass trap" to find out how you can build them yourself.

Those panels you have would work well on your first-reflection points.
Room modes terminate in the room corners. The place where three surfaces meet is therefore the most effective location for bass traps. In other words, at the top of the wall (where the two walls meet the ceiling), and at the bottom of the wall (where the two walls meet the floor). If you place your bass traps half way up the wall then you are not maximizing the effectiveness. They should be up at the ceiling or down at the floor, but not in the middle.

The ones for your first reflection points go roughly half way up the wall: centered about 120cm above the floor, at ear height.

As mrfantasticsaid: never put your speakers on the desk, or a shelf! Very true. You are doing right by having them on stands behind the desk, very close to the front wall. That's the correct place for them. However, you should stand them up vertically, instead of having them laid on their side. I'm posting an image down below to show you why that is.

Also, your bass traps will be far more effective on the rear wall, not on the front wall as you have them now. Put them in the two rear corners. I would out two of them in the floor (like you have them at present), then the third one hung horizontally across the top of the rear wall, angled diagonally so it straddles that corner, just like the other two should straddle the wall-wall corners diagonally.


You could use REW ( How to calibrate and use REW to test and tune your room acoustics ) to figure out what the issues are with the room, and help you decide how to treat it. REW is free, and very good at analyzing the acoustic response of your room. You can learn a lot about the room like that, then use that information to plan the treatment.


- Stuart -
Thank you so much for your detailed response Stuart. I am quite disappointed that i spend good money on these and they are not even bass traps ha but i suppose you live and learn. I looked at the bass traps mentioned and i have seen them before actually but then i have seen rectangle ones like mine used as well. The ones i have came from a professional studio but that does not mean they knew exactly what was best for them.

I understand the corners being the worst culprit for build up but my upper corners around the house have these things (see photo) so getting flush up top would be difficult. I still would rather have them up top as the room is carpeted so the bottom has some absorption at least.

I will definitely place my monitors vertically so thanks for that. Why did you say place them as close to back wall as possible? I think i may place stands behind desk and not directly to the side as they are pretty wide at the moment. That way i can save a tiny bit of space and they will also be even closer to back wall.

If you look at my room plan you will see i have double doors on the back wall and also the room door in the back left of the room (not ideal i know) it is also a rented property so not sure i will go with fixing anything to the ceiling. I'm not searching for perfection but just trying to make the most of what i have got. My songs usually get send off for the final mix to be polished and then mastered but i use the room for recording, writing, producing and getting a rough mix of where i want the song to be.
Attached Thumbnails
Help with placing acoustic treatment in my home studio (with dimensions and photos)-img_0459.jpg  
Old 4 weeks ago
  #6
You're welcome! Just to follow on a little - the speaker stand placement of behind the desk rather than to the sides may work for you - try it it out and see how it works although make sure you don't obstruct the speakers with your computer monitor or anything that blocks the sound at all.

Considering your bass traps - you wont have wasted money as such, just maybe not got quite what you thought - at least you have decent looking panels and not the foam type. Are they GIK panels? I'm wondering if you have the GIK Monster traps at 17 cms deep, in which case @ Soundman2020 is correct in that they are better suited to the rear wall although they will work ok straddling the corners if you have nothing else. Your front corners really need proper corner traps such as GIK tri traps or super chunks as soundman2020 mentioned. Those are ok free standing and stackable also which means no holes in the wall - noted that you're renting. Those are the best bang for buck in my experience with bass traps. I have a really awkward rear wall with window and door locations also with no possibility for tri traps or super chunks so have to use Monster traps as you seem to have there and they make a vast improvement so you will definitely benefit from them.

The other panels above the listening position would be great and can be mounted with a couple screws in most cases - depending on the ceiling material. Might be worth investigating and just patching up the holes when necessary. Similar with first reflection placement either side - a couple screws in the wall will work leaving only a small repair when you move out.

As soundman2020 mentioned REW is standard around here and super useful to post the results and have feedback from other more experienced acoustics guys on here, of which there are many offering great advice. I'm only learning slowly myself.
Old 4 weeks ago
  #7
Lives for gear
 

Quote:
Originally Posted by Jakeyboy29 View Post
Thank you so much for your detailed response Stuart. I am quite disappointed that i spend good money on these and they are not even bass traps ha but i suppose you live and learn.
I hope I wasn't too negative! What you have will still work for some things: just not for damping modal response way down low. There's a "rule of thumb" for porous insulation, based on comparing the thickness of the insulation against the wavelength. If you want absolute maximum absorption, then the front face of the trap should be 1/4 the longest wavelength you nee to deal with. But this isn0t very useful for small rooms, since the wavelength of the lowest modal resonances are very long. For example, assume you have a modal issue at 40 Hz: the wavelength is about 28 feet (8.6m), thus, based on this theory, you would need a panel 7 feet thick! (2.1m) And you would need that on both walls: so 7 feet thick on the front wall, and also 7 feet thick on the back wall... Ummm... that ain't gonna work, obviously! There would be zero space left in the room for you and the gear! Some ignorant people insist that this quarter wave rule) is the only valid way of building bass traps... Good luck to them in their 50 foot long rooms!

Fortunately, acoustic theory and real-world practice both show that you can get usable absorption down to 1/16 wavelength for "normally incident sound" (waves that hit the panel head-on), and for 1/32 wavelength for "random incidence sound" (waves that arrive at all angles with equal probability). So let's be realistic here, and assume that we are dealing with modal resonance, so those waves really will be normally incident... thus, 1/16 wave is the thickness you want. Assuming the same hypothetical room with a problem at 40 Hz, the wavelength is 28 feet: 28/16 = 1.75 feet = 21 inches = 53 cm. Thus, traps 53 cm thick would do the job of providing usable damping in this case (hypothetical!).

By the same token, and working backwards: your 17 cm traps would work for waves that are 17x16 = 272 cm long, which is nearly 9 feet... roughly 160 Hz. So no, when used flat against the wall, they are not bass traps. 160 Hz is in the low end, yes, and you might indeed have some modal issues around there in a typical small room, but the biggest problems will be much lower than that.

However, if you straddle them diagonally across the corner, then at least part of the front face is further away from the wall than 17cm: Depending on the room and the width of the panel, parts of the front face might be 35-40cm or so away from the corner itself, so you could expect to see some action down to around 60 Hz or so. They won't be highly effective down that low, since only some of the panel is that far from the wall, but you do still get an advantage.

You could get even more advantage by mounting the entire panel parallel to the wall (instead of straddling the corner) with an air gap behind it. For example a 43cm air gap, along with the 17cm thickness, places the front face 60cm from the wall: that would get you some coverage down to about 35 Hz, which is pretty much as low as you need it to go, usually. However, having the panel parallel to the wall means that it can only treat one wall: when it was straddling the corner, it could do two at once, but like this it can only do one. So you'd need another panel on the adjacent wall.

So, it's all about compromises! Better absorption, lower frequencies, or fewer panels? Pick any one, or maybe two, but not all three...

Quote:
I looked at the bass traps mentioned and i have seen them before actually but then i have seen rectangle ones like mine used as well. The ones i have came from a professional studio but that does not mean they knew exactly what was best for them.
That happens more than you'd think, actually! Sometimes I get hired to fix studios done by supposed "professionals", but that ended up with problems. And when I look at what they did, I often have to scratch my head, and wonder about the "professional" part...

Quote:
I understand the corners being the worst culprit for build up but my upper corners around the house have these things (see photo) so getting flush up top would be difficult.
You don't need to get flush up there! Mount them so they straddle the wall/ceiling corners, just like you would with a wall/wall corner!.

There are twelves corners in a rectangular room: All of them are equally useful for bass trapping. Many people only think of the four vertical corners, and forget about the other 8: you can put your traps in any of those, and get good results.

Quote:
I still would rather have them up top as the room is carpeted so the bottom has some absorption at least.
Ummm... I don't want to seem to harsh here about hour carpet, so I'll just point you at this article about carpet in studios.

Quote:
I will definitely place my monitors vertically so thanks for that. Why did you say place them as close to back wall as possible?
Front wall! Not back wall. The "front" wall of a studio is the one that is in front of you, as you sit at the mix position. It is behind the speakers, yes, but it is in front of you. The back wall is behind your back, way back there at the back...

Semantics, but important!

So, you want your speakers close to the front wall, because of something called "SBIR". In very simple terms, the very low frequency waves from the speaker go out in all directions around it (not just towards you), including behind the speaker, where they hit the front wall, bounce back, then interfere with themselves, causing causing cancellations of some frequencies. Big "holes" in the frequency response at some points in the room. SBIR stands for "Speaker Boundary Interference Response", and the location of the first "hole" in the sound, is given by a very simple equation: the distance between the front baffle of the speaker (where the cones are), and the wall. There is a range of distances that causes the first "hole" or "dip" to appear at very lousy frequencies, where it will mess with your perception of bass in the room, and which cannot be treated easily. I'm attaching an image to show you this in simple graphic form, with a table of distances showing good ones and bad ones. Red numbers = very bad, blue numbers=still bad but might possible be usable. Green numbers = no problem. As you can see you either need to have the speaker very fare form the wall (more than 3 meters (10 feet), or you must hae it right up as close as you can get it.


Quote:
I think i may place stands behind desk and not directly to the side as they are pretty wide at the moment. That way i can save a tiny bit of space and they will also be even closer to back wall.
Front wall...

For any give room, there is an optimum layout (geometry) for the speakers and mix position. You often see the famous "equilateral triangle" in books, showing the speakers and mix position at the three corners of a triangle where all the angles are 60°. Hmmm... wellll ....sort of. That works somewhat for most rooms (which is why they put it in the manuals!), but it probably wont be optimum. There's a procedure that I call the "Walking Mic test" (see here: "Walking Mic" test procedure, for finding optimum mix position location (and other things) ), that can help you find that optimum spot for the mix position. It also describes how you can do the same thing for the speakers, but without going into all the details.

Quote:
If you look at my room plan you will see i have double doors on the back wall and also the room door in the back left of the room (not ideal i know) it is also a rented property so not sure i will go with fixing anything to the ceiling. I'm not searching for perfection but just trying to make the most of what i have got. My songs usually get send off for the final mix to be polished and then mastered but i use the room for recording, writing, producing and getting a rough mix of where i want the song to be.
Even so, try playing around with REW, and use what it tells you to put your panels to the best use.


- Stuart -
Attached Thumbnails
Help with placing acoustic treatment in my home studio (with dimensions and photos)-neumann_loudspeaker_boundary_location_v02-sbir-table-wall-bounce-distance.jpg  
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