Mixing Room - Acoustic Treatment!

[CuriousErez]

Hey All, My first post here : )
My name is Erez and I am from Israel,
producing music and Djinn for the pat 5 years.
Moved to a new apartment and I want to get the room ready for proper mixing.
sharing with you my specs and REW measurements and maybe you could suggest me from where to start from?
how to place my speakers?
what acoustic treatment to buy and where to put it?

** and I am having the worst flutter effect in the room, a hand clap is bouncing for 3 seconds -_-

- I am using Kali Audio LP-6 speakers
- the room dimensions are:
length - 312
width - 263
height - 260

left wall is made from plaster : (

here is the measurements from REW

and I am also attaching measurements from Sonarworks (

 

[Hipper]

I don't know what the requirements are for a mixing room - I'm sure some on here do - but understand that Gearslutz (I see it's now called Gearspace) is the more likely place for advice:

Gearspace.com

Forum for professional and amateur recording engineers to share techniques and advice.

gearspace.com

Anyway, to help those on here I suggest you post REW SPL graphs with a smaller SPL range, say 110-50dB, and with no smoothing. This will help with understanding how the bass notes behaving, the first part of the frequency response to deal with.

 

[Flaesh]

here is the measurements from REW

You may download .mdat

 

[pozz]

It all depends on budget. Production is extremely expensive if you go into this with the idea to get the best. The goal is to simply get to the point where you can make music.

No matter what, when your tracks get good, you will be sending them to a pro mastering engineer anyway and they will polish them. So you don't need to get all of the details absolutely right, which means that you can also spend less on the room.

Bass especially will be a problem, especially the very low bass. Even after doing everything it will likely be suboptimal, but you can check the bass in your mix with headphones. You could buy a subwoofer or two if you have the budget for it, but integration is not easy. At all. Just look at how many threads are on this one topic on ASR. (It does sound great when done right, though.)

You can do some of the following: mount thick (8" or 4" with 4" air gap) porous treatment at ear height on the side walls and on the ceiling, with a space coupler diffusor under that. Mount diaphragmatic (panel type) treatment directly on the front wall behind the speaker. Ideally, you'd put either 1D or 2D diffusors on the back wall behind you but, because your room is very small, it will make the diffusion ineffective. So you can repeat the absorber and space coupler combo on the back wall.

If you have a window, you can mount a second pane of glass/plastic inside the frame and seal the edges. Otherwise, seal the edges of outlets and vents inside the room. Seal the door using weatherproofing. This will cut the noise inside your room significantly and make it easier to mix.

Keep it cheap. There's a lot to learn, and it seems a lot of the time that money will solve problems which really need some understanding and research. Cheap doesn't mean, however, that you can buy 2" treatment and expect it to be mostly as good. It's not. There are underlying principles. But asking questions is free.

In terms of speaker placement: the overall placement should be symmetrical with respect to the walls and room. The speakers should be close to the back wall. and angled towards you in a triangle. The central point of the triangle should be a little behind your head. None of this has to be super precise, although you can do it with a laser measure if you like. You can measure and do some basic room EQ work up to a few hundred Hz too.

Let me just repeat that: none of this has to be super precise. You have good speakers, a measurement mic and your own place, which means you're almost all the way there.

The more you obsess about your room, etc., the less music you'll end up making.

 

[pozz]

Truer words were never spoken! Jim

From experience

 

[alex-z]

If you can actually hear the echo of a hand clap after 3 seconds your room has some serious decay time problems. The best thing to start with is placing mineral wool panels at your first reflection points, especially ceiling and side walls. Super easy and cheap to DIY. Mineral wool is commonly sold under the rockwool or roxul brands. Use 5.5" if possible for better bass absorption, but 3.5" still works well.

Air gap the panels off your walls if possible, it enhances low frequency performance.

Speaker distance from the wall is always a compromise. I personally prefer my speakers close to the walls, so that acoustic treatment can be placed behind them, and absorb the reflection. Others prefer to pull their speakers far away, so that the reflection falls into the bass region, and can be managed with subwoofers.

Speaker Placement 101: Is Speaker-Boundary Interference Killing Your Bass?

Not hearing enough bass through your monitors? The distance between your room boundaries and speakers has a huge impact on your bass performance. This tutorial will show you specific strategies for placing your speakers to get a balanced bass response.

arqen.com

SBIR calculator

SBIR calculator

tripp.com.au

Create some new measurements, 3 for each channel, with the microphone at your listening position, and 1 metre to either side. Then upload the .mdat file, so that we can get a look at the waterfall and impulse response data.

 

[CuriousErez]

Thank you ALL guys! really appreciate your help : )

I don't know what the requirements are for a mixing room - I'm sure some on here do - but understand that Gearslutz (I see it's now called Gearspace) is the more likely place for advice:

Gearspace.com

Forum for professional and amateur recording engineers to share techniques and advice.

gearspace.com

Anyway, to help those on here I suggest you post REW SPL graphs with a smaller SPL range, say 110-50dB, and with no smoothing. This will help with understanding how the bass notes behaving, the first part of the frequency response to deal with.

attached - measurements with smaller db. range and no smoothing, also a new speaker placement - the listening position is closer to the back wall (38% from it) and a triangle with 163 cm between each point.

It all depends on budget. Production is extremely expensive if you go into this with the idea to get the best. The goal is to simply get to the point where you can make music.

No matter what, when your tracks get good, you will be sending them to a pro mastering engineer anyway and they will polish them. So you don't need to get all of the details absolutely right, which means that you can also spend less on the room.

Bass especially will be a problem, especially the very low bass. Even after doing everything it will likely be suboptimal, but you can check the bass in your mix with headphones. You could buy a subwoofer or two if you have the budget for it, but integration is not easy. At all. Just look at how many threads are on this one topic on ASR. (It does sound great when done right, though.)

You can do some of the following: mount thick (8" or 4" with 4" air gap) porous treatment at ear height on the side walls and on the ceiling, with a space coupler diffusor under that. Mount diaphragmatic (panel type) treatment directly on the front wall behind the speaker. Ideally, you'd put either 1D or 2D diffusors on the back wall behind you but, because your room is very small, it will make the diffusion ineffective. So you can repeat the absorber and space coupler combo on the back wall.

If you have a window, you can mount a second pane of glass/plastic inside the frame and seal the edges. Otherwise, seal the edges of outlets and vents inside the room. Seal the door using weatherproofing. This will cut the noise inside your room significantly and make it easier to mix.

Keep it cheap. There's a lot to learn, and it seems a lot of the time that money will solve problems which really need some understanding and research. Cheap doesn't mean, however, that you can buy 2" treatment and expect it to be mostly as good. It's not. There are underlying principles. But asking questions is free.

In terms of speaker placement: the overall placement should be symmetrical with respect to the walls and room. The speakers should be close to the back wall. and angled towards you in a triangle. The central point of the triangle should be a little behind your head. None of this has to be super precise, although you can do it with a laser measure if you like. You can measure and do some basic room EQ work up to a few hundred Hz too.

Let me just repeat that: none of this has to be super precise. You have good speakers, a measurement mic and your own place, which means you're almost all the way there.

The more you obsess about your room, etc., the less music you'll end up making.

I cant agree more with you! I am tired of preparing to making music and not actually making it.
I actually have the KRK SUB (8\10 inch, not sure) just need to hook it up.

could you please post links\pictures to the types of treatments? I am not familiar with all the acoustics concepts.

forgot to mention that one of the walls is plater wall, here is a quick sketch of the room:

If you can actually hear the echo of a hand clap after 3 seconds your room has some serious decay time problems. The best thing to start with is placing mineral wool panels at your first reflection points, especially ceiling and side walls. Super easy and cheap to DIY. Mineral wool is commonly sold under the rockwool or roxul brands. Use 5.5" if possible for better bass absorption, but 3.5" still works well.

Air gap the panels off your walls if possible, it enhances low frequency performance.

Speaker distance from the wall is always a compromise. I personally prefer my speakers close to the walls, so that acoustic treatment can be placed behind them, and absorb the reflection. Others prefer to pull their speakers far away, so that the reflection falls into the bass region, and can be managed with subwoofers.

Speaker Placement 101: Is Speaker-Boundary Interference Killing Your Bass?

Not hearing enough bass through your monitors? The distance between your room boundaries and speakers has a huge impact on your bass performance. This tutorial will show you specific strategies for placing your speakers to get a balanced bass response.

arqen.com

SBIR calculator

SBIR calculator

tripp.com.au

Create some new measurements, 3 for each channel, with the microphone at your listening position, and 1 metre to either side. Then upload the .mdat file, so that we can get a look at the waterfall and impulse response data.

what is the sbir calculator for?

1. maybe the plater wall is responsible for the serious flutter effect?
2. what about bass traps? which one should I get, how may, and where to put them?
3. thought about building wood diffusers myself, I got all the wood gear, just need a good instruction for it.
4. could you send me to a good guide to start with the sub placement

 

[pozz]

could you please post links\pictures to the types of treatments?

Sure.

• Space coupler:
  Spoiler

  
• Porous absorber (foam, specifically Basotect):
  Spoiler

  
• Porous absorber (fibreglass):
  Spoiler

  

  
• 1D diffusor:
  Spoiler

  
• 2D diffusor:
  Spoiler

  

  
• Panel/membrane/diaphragm absorber (just an example):
  Spoiler

  

I'm not sure what would be available in Israel. GIK, RealTraps and RPG are reputable. The latter is very expensive.

forgot to mention that one of the walls is plater wall, here is a quick sketch of the room:

The wall material is no biggie. Same process/thinking applies. You aren't going to rebuild your room from scratch, you know.

 

[ernestcarl]

Thank you ALL guys! really appreciate your help : )



attached - measurements with smaller db. range and no smoothing, also a new speaker placement - the listening position is closer to the back wall (38% from it) and a triangle with 163 cm between each point.





I cant agree more with you! I am tired of preparing to making music and not actually making it.
I actually have the KRK SUB (8\10 inch, not sure) just need to hook it up.

could you please post links\pictures to the types of treatments? I am not familiar with all the acoustics concepts.

forgot to mention that one of the walls is plater wall, here is a quick sketch of the room:

View attachment 162016


what is the sbir calculator for?

1. maybe the plater wall is responsible for the serious flutter effect?
2. what about bass traps? which one should I get, how may, and where to put them?
3. thought about building wood diffusers myself, I got all the wood gear, just need a good instruction for it.
4. could you send me to a good guide to start with the sub placement

Took a quick peak at your measurements... you need to do more absorbing treatment than diffusion.

Reflections (mid-hi frequencies) are too strong in the right measurement -- mic was too close to a reflective boundary?:

see the early peak around 6ms is very strong

Center trace is sort of the "best" (not counting the gigantic bass hole) because it's also farthest from all boundaries.


Right position mic placement is causing havoc with the direct sound with what looks like a comb filter effect (blue trace) below:

Center position might be best for stereo imaging, but it's kind of also the worst in the bass department, too.

The response measurements from your current positioning/placement is not the best.

You might want to try experimenting with placing the speakers as tightly to the wall as possible -- as well as your listening position to the speakers. In other words, try to compress the listening "triangle".

When you have time, look at videos/articles discussing SBIR, room modes, and acoustic treatment. Audioholics has plenty of good ones (though lengthy, often with Anthony Grimani and/or Matthew Poes) found on youtube if you do a quick search. There's also Jesco (shorter videos) -- he specializes in treating home mixing/studio rooms. It would help you to at least visualize what these issues are and how they can be addressed esp. with the aforementioned acoustic treatment products.

*Sorry, I just realized that's not "right position", but right monitor (mtr rght).

 

[Soundmixer]

Center position might be best for stereo imaging, but it's kind of also the worst in the bass department, too.

This is why I would recommend incorporating a subwoofer into the OP monitoring system. He could keep the center position which is best for stereo imaging and put the sub in the best place for room integration via equalization. You don't have to choose here, you can have both.

 

[CuriousErez]

*Sorry, I just realized that's not "right position", but right monitor (mtr rght).

you were right! it did meant : 1 meter to the right (from listening position)

 

[ernestcarl]

This is why I would recommend incorporating a subwoofer into the OP monitoring system. He could keep the center position which is best for stereo imaging and put the sub in the best place for room integration via equalization. You don't have to choose here, you can have both.

I agree. Here's nothing more than a "theoretical simulation" I concocted in REW -- if he's able to have a sub in-room measure perfectly, that is:

Upper bass and mids suckout would still need to be dealt with the appropriate acoustic treatment.

 

[ernestcarl]

you were right! it did meant : 1 meter to the right (from listening position)

There were multiple strong reflection peaks in the IR of that measurement. Maybe one of them was from the heater device on the right wall side? Dunno. Just a guess.

 

[CuriousErez]

There were multiple strong reflection peaks in the IR of that measurement. Maybe one of them was from the heater device on the right wall side? Dunno. Just a guess.

might be! its made from metal and its pretty big. I will do another one just to sure.

I agree. Here's nothing more than a "theoretical simulation" I concocted in REW -- if he's able to have a sub in-room measure perfectly, that is:

View attachment 162285

Upper bass and mids suckout would still need to be dealt with the appropriate acoustic treatment.

what this graph mean?

and about the sub - I will connect it but maybe you could send me to a good starting guide for sub placement?

 

[dasdoing]

length - 312
width - 263
height - 260

in a very small room like this you have no option but to make it pretty dead.
frontwall with corners straddled, frontwall fully absorbive at least at speaker hight. sidewalls fully absorbive from frontwall to "mirror position", at least at speaker hight. ceiling cloud.
here at home it looks like this: https://www.audiosciencereview.com/...-treatment-products.12439/page-12#post-921575
and at the backwall you want tons of absorbtion. as thick as possible. and if possible the whole wall. reason is that the first longitunal room mode is the most anoying in a small room. it rings "forever", even after EQ.
make sure to not use carpet, else it will sound terrible as you will have no HF reflection left at all

 

[Frgirard]

Sure.

• Space coupler:
  Spoiler

  
• Porous absorber (foam, specifically Basotect):
  Spoiler

  
• Porous absorber (fibreglass):
  Spoiler

  

  
• 1D diffusor:
  Spoiler

  
• 2D diffusor:
  Spoiler

  

  
• Panel/membrane/diaphragm absorber (just an example):
  Spoiler

  

I'm not sure what would be available in Israel. GIK, RealTraps and RPG are reputable. The latter is very expensive.

The wall material is no biggie. Same process/thinking applies. You aren't going to rebuild your room from scratch, you know.

Diffusor in a little room is a non sens.

The place to receive skill advices is not an audiophile forum but Gearspace.com or John slayers forum.

 

[Frgirard]

Truer words were never spoken! Jim

The audiophiles think they can bend the light the eyes.
another example here.

 

[pozz]

Diffusor in a little room is a non sens.

The place to receive skill advices is not an audiophile forum but Gearspace.com or John slayers forum.

Do you read before posting?

Ideally, you'd put either 1D or 2D diffusors on the back wall behind you but, because your room is very small, it will make the diffusion ineffective.

 

[ernestcarl]

what this graph mean?

As I said, it was just an imaginary simulation -- assuming you could get a perfect sub measurement in-room coupled to your current mains. You can try to predict how a real sub would interact with the dimensions of your room (and mains) by using REW's room simulator window module:

Then again, this is also nothing more than a simulation -- assuming that the walls in the room are infinitely rigid, and that the room's geometry is perfectly cuboid in shape.

The problem with people starting out viewing and reading measurements without experience is, as Jesco in that video link said, might end up more "confused" than when they started out.

Integrating a sub is not going to be that easy or perfect even if you follow the general "guidelines" out there -- opinions vary.

and about the sub - I will connect it but maybe you could send me to a good starting guide for sub placement?

There's a lot "guides" if you search the web and visit various audio related forum threads, but I haven't particularly bookmarked any single one, sorry.

The room simulator might already be able to help give you some idea where, if you play around with it... but, because the crossover required to fill in that cavern is going to be quite high ~120Hz, you really only have a few options to do so without the problem of "localization": it has to be somewhere in between the two mains, in front of you, close to both speakers rather than at a distance -- but as a starting point, you could try pushing it right against the front wall. Though, again, caveat emptor: the room is going to dictate the final outcome, and you still may not like the measured response you get.

 

[ernestcarl]

and about the sub - I will connect it but maybe you could send me to a good starting guide for sub placement?

I was wrong! So I searched my bookmarks and actually found two very old articles, mind you:

Choosing & Installing A Subwoofer

Subwoofer Placement - The Place for Bass

*The latter looks to be for a "home theater" setting rather than home studio.

I only vaguely remember reading the two above many years ago. Pretty sure a lot of newer -- even better or more detailed -- "guides" are out there now.