Without a doubt these presentations are the single best resource for Acoustics I know of. Dennis, your ability to summarize these very complex concepts, while remaining practical is incredible. FYI I studied Acoustics at University for two years (20 years ago), and have been obsessed with the topic ever since. I still consider myself a learner, these videos are a gold mine to me :) Keep it up!
Your presentations (rightly so) focus on recording studio type environments. Im currently working on improving the sound of a small dancefloor/room for a club. its a concrete rectangular box 8.84m L x 5.38m W x 2.57h (with cieling going to 4ish metres). Its a great challenge to get it to sound good while keeping the bass that gets out under control. We have a pair JBL 715 Active Speakers, which have 15" drivers are WAY TO BIG for that room. The 18" RCF Subwoofer is borderline gratuitous, and Im gradually convincing everyone that we dont need it.A dbx Driverack PX made a great improvement inside (a really great product FYI), but I want to control the 135hz boom/hum that travels out of it into the large foyer, and then outside (Neighbor issues). (I found that was the frequency using the iPhone "Audio Audit" app - very useful. Im thinking polystyrene "cityscape" QDAs on the ceiling to scatter as much of the bass as possible, and breakup the standing waves (its pretty obvious to me that the foyers floor to ceiling surfaces are the main cause. Changes inside the danceroom wont be effective, as the DJs will just turn it/adjust their EQs till it sounds the way they want, so we can only take action outside the room. Sorry for the long Preamble :). Do you have any generic advice for dancefloors? Im also thinking of making a big diffuser for the back wall to make it "disappear", I assume that would be a good Idea generally. Im also thinking of making some bass "disrupters" for the corners, they wont be able to trap that bass(I also dislike the implications of the term "Bass Trap"), but they can stop it getting too settled in one place :) Once again thanks, Im sure you are very busy, any even non specific advice would be greatly appreciated. Thanks :)
Thanks again. Today I started placing the absorbtion I can afford at the time, and I was confused due to the live-end / dead-end discussion on the net. From previous home studio setups, I have the experience that the listening position was crucial to get right. That also involves the direct response from behind. When everything was right in listening position last time, the rear wall standing Waves towards listening position was all I needed to adress. Now you reassured me that starting in the listening area was the way to go. Thank you for the videos.
Thank you for this explanation! Question. I have a rehearsal room and I would like to reduce sound reflexions from it. In this case, the sound pressure comes from the gtr, bass cabinets, and the drum set. Meaning that I have several sound sources placed in different areas of the room. Having said that, the questions are: + How can I control reverberation time without killing/drying the room that much? + How should I place my acoustic panels in this situation in order to get a cleaner and clearer room sound for music rehearsal? Thank you in advance for taking you time reading this.
A, Reverberation times are usage dependent and subjective in nature. With multiple sources in a small room, start by treating 50% of each wall surface area. Use the room for awhile and then make the additions or subtractions in absorption materials.
Im building a vocal booth for one. I was wondering do you need to absorb the bass in the room for that? im doing it from the ground up. tips and pointers would be cool as well. Much appreciated Aubry.
Hi Aubry, Male vocals start around 100 Hz. Unless you are recording numerous male vocals, low frequency issues are not a problem. Diffusion works well for vocals. Make sure to include it in your vocal booth design.
Like have diffusion walls in the booth? I was planning on foam and plywood. And it willl just mainly be me with my male vocals. I rap as well as produce.
Hi. First let me thank you for your informative and useful videos. I recently moved to a new place and figuring out all these issues. I mostly use Roxul Safe and Sound insulation pads. However my question here is [ I have all 4 corners in the room treated with floor to ceiling panels. How thick should they be? Currently I used only 1 layer of Roxul, but I suspect at least 3-4 layers thick would be the way to go for corners?
Hi Sebastian, I must have more information about your room. Remember, that the highest pressure areas are usually not in the corners of your room. Fill out the information in this link: www.acousticfields.com/free-room-analysis/
Would crumb rubber be a suitable limp mass for a large-scale DIY bass trap? I'm unsure about sound energy absorption as well as the consideration with the material off-gassing in a closed environment. It seems that activated carbon is too expensive for sufficient coverage in an auditorium. What are the alternatives for bass trap materials?
Hi Samuel Haywood The best way to figure out if a material will work as a low frequency absorption technology is to build the unit and have it tested at an accredited lab for verification of your initial hypothesis. An auditorium by definition at least here in the states is a larger volume that can sustain low frequency waves. Auditoriums are notorious for high reverberation times which is a middle and high frequency issue. Thanks Dennis
Hi Dennis and folks. I have no doubt about your knowledge.! But I have (40cm deep) of Bass absorber 50x100x40 cm behind left and right main front speakers from aixfoam (Open-cell PUR acoustic foam) and it does work exceptionally well.! Thanks for your great videos 🙏✌️
Foam lacks the proper rates and levels to deal with the pressure levels behind speakers and the front wall. You must apply the proper technology within the room positions to deal with those specific issues.
@AcousticFields I'm sure you have a video about it, but most people don't understand the difference between pressure and velocity based absorbers. Velocity based "traps" are not very good at low frequency absorbtion. Also probably doesn't help that you sell foam panels that probably 85+ percent of people consider "bass traps", while also saying how bad foam can be. Though I'm sure most of the time you reference foam in your videos, you are likely talking about the "cheap" 1 inch thick panels people buy on Amazon. Ends up costing them way more per square foot than if they just did some diy mineral wool absorbers. Plus the mineral wool absorbers will reach down significantly lower.
Hey Dennis. Great video. I have a peculiar problem in a room where the surface behind the speakers is glass. It's customised doubled paned glass of 12mm and 10mm thickness at a small angle. This used to be a window and was sealed this way for isolation. However the surface is quite reflective and placing absorbers on that surface is also quite difficult. Especially since the user doesn't want the natural light to be blocked either. How do I deal with this?
Thanks, again! Best explanation of bass 'waves' ["pressure"] i've heard. Know of your different products; to combat different acoustic abnormalities. Is there one single wall [entire surface] treatment that adequately/efficiently addresses the whole [human] frequency range? Remember cork walls?!?! hahaha All the best.
I see in this video you talk about bass absorption on the front wall. I believe in others you talked about putting diffusion on the front wall. For my listening room I had pre-envisioned (as a starting point) to put diaphragmatic absorbers in the two front corners with diffusion between them. But now I'm wondering if I'd be better off with more bass absorption in that area. I realize data will help me out when I have it. How do I determine which will be best? (I have to confess the RTA room measurement process scares me. Last time i accidentally blew my speakers causing thousands of dollars in damage).
R, Low frequency management is all about TAP (type, amount, position). You must select the correct type of low frequency technology you are going to need. Remember, there are three types of low frequency absorption technologies. This decision is based upon frequency and amplitude of the low frequency issues within your room size and volume. Amount refers to the square footage requirement of that chosen treatment and position is where to locate the technology. starting with low frequency absorption on the front wall area is a good start. Most front wall areas have high pressure issues because the speakers are close to that boundary surface. Most rooms we design have 40 - 60 sq. ft. of low frequency management technology on the front wall.
I have also found days ago that the front wall is more important than the corners; and just discovered the video now where you talk about the myth corners. Thank you for confirming my suspicions. How much height would you say is important in relation to the ears to cover? from floor to ceiling? And to the sides? If the axis are the important thing to cover and you are relative far from the corners, do you think abortion there is not that much worth it? Is it better to leave as much distance as possible between the wall and the absorption? As I understand it, the higher the speed, the greater the absorption, the opposite of the closer it is to the wall. Is placing the abortion right behind the speakers silly? Well, thank you for your content Dennis
Hi djalexgee Many thanks. I have a subwoofer video coming out in a couple of weeks. Best to wait for that as it shows room placement. If you make sure you're subscribed to our channel you will get an alert when it is posted. Thanks
G, It is one option. If you place diffusers on the back wall of planars, you should also treat the rear wall with diffusion. If you can not do both walls then absorption for front wall and diffusion for rear.
Hello Dennis, your videos are really insightful. Thank you very much for all the wisdom shared. I wanted to ask you, do you recommend any kind of fabric when wrapping the panels? Especially when using fiberglass as the absorption source. So you don't get to breathe those harmful particles it produces. Thank you very much.
@@AcousticFields That's right Dennis, thank you for your response. I was really asking which fabric or material do you recommend when covering the fiberglass to prevent this from happening. Thank you once again in advance. Wish you a great day.
I understand that this is easy to overabsorb using acoustic foam, which will result in "dead" sound. But my question is; is it possible to overabsorb low end using pressure activated devices? Or is it "more absorbers = better" rule?
Hi Daniel, You must quantify the low frequency issues within your room through measurements by developing a strategy that deals with the frequency and amplitude of the low frequency issues within your room. If you are over absorbing or under absorbing, you are using guessing as a tactic without a sonic strategy. Guessing is gambling. I am not a fan of either. We have a saying in our office: Don't hope - know.
Hi Dennis, I just built 4 broadband 4" bass absorbers, plan to place them in each ceiling corner of room, so they are kind of angled, they come a bit out from the corner though and leaves quite a space. is this still a good use of the panels or is placing them vertical to the corner more advisable. thank you for your time and videos. N.
Acoustic Fields nope, there punk diy Rockwood slapped onto a cheap wood frame with some kasmiri clone fabric slabs, there about 180cm x 60cm x 4 inch thick. I'm approached this project with wreckless abandon and thrown the absorbers in the corners with the attention not unlike Coltrane s mid interstellar solos to being in key. appreciate your reply sir, I can send ya a pic if necessary, cheeri-O. 🎶
M, Without knowing the frequency response of the unit, it is difficult for me to assist you. With a 4" depth and a building insulation fill, you will be absorbing from 90 Hz. and above. This unit would not qualify as a broadband low frequency absorbing device. What is your room size/volume/usage of the room?
Acoustic Fields Dennis, appreciate your time, I see, well the dimensions are 12.5x11.7x8.1ft, the speakers are currently placed parallel to the lengthier side, about 20cm from the wall with a king size matress in between. the opposite also has a 15cm width king size matress, there is also a couple of sofas. the room is for mixing and production, it would be great if I could bring it up to a level for mastering.critical listening is saught after, I'm hoping to create a RFZ (reflection free zone) for the mix position which is now almost right smack in the center of the room. sitting on the sofa in the back end of the wall opposite the sound has a huge bass boost which is almost desirable as clients can get a more home theatre vibe when listening back :) at least that's how keep positive about it,:) mix position accurate sound is what I'm going for, nothing on the ceiling yet, but I'm planning another bass absorber or two installations up there along with some fractal diffusers... live in Taiwan so not sure what materials would be available at what cost if you recommend something, cheers man, 🍻
Hey, thanks for your video! So I'm dealing with this. I have a substantial amount of low frequencies building up in the middle of my home studio (1 room, both for recording and listening). I have big superchunk bass traps in all corners. I have a big window in front of the room and would not like to cover this with bass reducing devices. Would it help to make a big bass trap all over the rear wall? I understand it's hard to judge when not having the precise measurements of the room.
L, This is a good example that putting absorption in the corners does not have the desired impact. Axial modes are produced by two walls so you must treat both offending walls.
@@AcousticFields Would it help to get a subwoofer and move this around or should I focus on the room first? Also, will 1 sub woofer be enough to deal with this?
Hi Casovini, Most of the time it is more broadband low frequency coverage. We use 30 Hz. - 200 Hz. However, sometimes you need more frequency specific absorption from 30 - 50 Hz. It depends on the ceiling to floor dimension along with the width dimension. Low frequency driver number and diameter plays a part as well as their locations within the room size and volume. There is no one size fits all.
Question: Is this video only assuming a two full range loudspeaker setup? In my setup I have everything below 100hz going to a sub,, so does that mean it's lower priority to treat behind the speakers now?
+Scott smith Room size and volume are the critical factors in dealing with low frequency energy. The unwanted low frequency pressure areas manifest themselves in different locations depending on room size and volume. Fill out the information in this link and I can assist you with those issues and the appropriate treatment. www.acousticfields.com/free-acoustic-treatment-room-analysis-tell-us-room/
Without a doubt these presentations are the single best resource for Acoustics I know of.
Dennis, your ability to summarize these very complex concepts, while remaining practical is incredible.
FYI I studied Acoustics at University for two years (20 years ago), and have been obsessed with the topic ever since. I still consider myself a learner, these videos are a gold mine to me :)
Keep it up!
Thank you for your support. If you have any topics you would like to see covered in this video format, do not hesitate to ask.
Your presentations (rightly so) focus on recording studio type environments. Im currently working on improving the sound of a small dancefloor/room for a club. its a concrete rectangular box 8.84m L x 5.38m W x 2.57h (with cieling going to 4ish metres). Its a great challenge to get it to sound good while keeping the bass that gets out under control. We have a pair JBL 715 Active Speakers, which have 15" drivers are WAY TO BIG for that room. The 18" RCF Subwoofer is borderline gratuitous, and Im gradually convincing everyone that we dont need it.A dbx Driverack PX made a great improvement inside (a really great product FYI), but I want to control the 135hz boom/hum that travels out of it into the large foyer, and then outside (Neighbor issues). (I found that was the frequency using the iPhone "Audio Audit" app - very useful. Im thinking polystyrene "cityscape" QDAs on the ceiling to scatter as much of the bass as possible, and breakup the standing waves (its pretty obvious to me that the foyers floor to ceiling surfaces are the main cause. Changes inside the danceroom wont be effective, as the DJs will just turn it/adjust their EQs till it sounds the way they want, so we can only take action outside the room.
Sorry for the long Preamble :).
Do you have any generic advice for dancefloors? Im also thinking of making a big diffuser for the back wall to make it "disappear", I assume that would be a good Idea generally. Im also thinking of making some bass "disrupters" for the corners, they wont be able to trap that bass(I also dislike the implications of the term "Bass Trap"), but they can stop it getting too settled in one place :)
Once again thanks, Im sure you are very busy, any even non specific advice would be greatly appreciated.
Thanks :)
These videos have been very helpful! Thanks Dennis.
Glad you like them!
Thanks again. Today I started placing the absorbtion I can afford at the time, and I was confused due to the live-end / dead-end discussion on the net. From previous home studio setups, I have the experience that the listening position was crucial to get right. That also involves the direct response from behind. When everything was right in listening position last time, the rear wall standing Waves towards listening position was all I needed to adress. Now you reassured me that starting in the listening area was the way to go. Thank you for the videos.
amazing presentation! simple and crystal clear! thankyou so much!
Glad you enjoyed it!
You give us guide, master🙏
My favorite video so far. Excellent job!
I seriously love your videos. They are so informative! Thank you for what you do.
M, Thank you for your support.
Thank you for this explanation!
Question. I have a rehearsal room and I would like to reduce sound reflexions from it. In this case, the sound pressure comes from the gtr, bass cabinets, and the drum set. Meaning that I have several sound sources placed in different areas of the room.
Having said that, the questions are:
+ How can I control reverberation time without killing/drying the room that much?
+ How should I place my acoustic panels in this situation in order to get a cleaner and clearer room sound for music rehearsal?
Thank you in advance for taking you time reading this.
A, Reverberation times are usage dependent and subjective in nature. With multiple sources in a small room, start by treating 50% of each wall surface area. Use the room for awhile and then make the additions or subtractions in absorption materials.
Im building a vocal booth for one. I was wondering do you need to absorb the bass in the room for that? im doing it from the ground up. tips and pointers would be cool as well. Much appreciated Aubry.
Hi Aubry,
Male vocals start around 100 Hz. Unless you are recording numerous male vocals, low frequency issues are not a problem. Diffusion works well for vocals. Make sure to include it in your vocal booth design.
Like have diffusion walls in the booth?
I was planning on foam and plywood. And it willl just mainly be me with my male vocals. I rap as well as produce.
thank you for coming back to me.
Hi. First let me thank you for your informative and useful videos. I recently moved to a new place and figuring out all these issues. I mostly use Roxul Safe and Sound insulation pads. However my question here is [ I have all 4 corners in the room treated with floor to ceiling panels. How thick should they be? Currently I used only 1 layer of Roxul, but I suspect at least 3-4 layers thick would be the way to go for corners?
Hi Sebastian, I must have more information about your room. Remember, that the highest pressure areas are usually not in the corners of your room. Fill out the information in this link: www.acousticfields.com/free-room-analysis/
How big - rule of thumb - absorbers behind the speakers have to be?
Depends on gas flow resistivity of the absobtion material, and what frequencies you are trying to hit.
Would crumb rubber be a suitable limp mass for a large-scale DIY bass trap? I'm unsure about sound energy absorption as well as the consideration with the material off-gassing in a closed environment.
It seems that activated carbon is too expensive for sufficient coverage in an auditorium.
What are the alternatives for bass trap materials?
Hi Samuel Haywood
The best way to figure out if a material will work as a low frequency absorption technology is to build the unit and have it tested at an accredited lab for verification of your initial hypothesis.
An auditorium by definition at least here in the states is a larger volume that can sustain low frequency waves. Auditoriums are notorious for high reverberation times which is a middle and high frequency issue.
Thanks
Dennis
Thank you for the helpful response, Dennis. Your videos are all very informative.
Hi Dennis and folks. I have no doubt about your knowledge.! But I have (40cm deep) of Bass absorber 50x100x40 cm behind left and right main front speakers from aixfoam (Open-cell PUR acoustic foam) and it does work exceptionally well.! Thanks for your great videos 🙏✌️
Foam lacks the proper rates and levels to deal with the pressure levels behind speakers and the front wall. You must apply the proper technology within the room positions to deal with those specific issues.
@AcousticFields I'm sure you have a video about it, but most people don't understand the difference between pressure and velocity based absorbers. Velocity based "traps" are not very good at low frequency absorbtion. Also probably doesn't help that you sell foam panels that probably 85+ percent of people consider "bass traps", while also saying how bad foam can be. Though I'm sure most of the time you reference foam in your videos, you are likely talking about the "cheap" 1 inch thick panels people buy on Amazon. Ends up costing them way more per square foot than if they just did some diy mineral wool absorbers. Plus the mineral wool absorbers will reach down significantly lower.
Hey Dennis. Great video. I have a peculiar problem in a room where the surface behind the speakers is glass. It's customised doubled paned glass of 12mm and 10mm thickness at a small angle. This used to be a window and was sealed this way for isolation. However the surface is quite reflective and placing absorbers on that surface is also quite difficult. Especially since the user doesn't want the natural light to be blocked either. How do I deal with this?
L, We make a product for just such as issue. It is our foam sliding panel. www.acousticfields.com/product/sound-absorbing-panels-for-windows/
Thanks, again!
Best explanation of bass 'waves' ["pressure"] i've heard.
Know of your different products; to combat different acoustic abnormalities.
Is there one single wall [entire surface] treatment that adequately/efficiently addresses the whole [human] frequency range?
Remember cork walls?!?!
hahaha
All the best.
S, Cork walls would be a middle and high-frequency absorption technology. Our CAW Carbon Absorbing Wall addresses all issues from 30 - 6,500 Hz.
Acoustic Fields
TY
All your vids are getting rave reviews; congrats!
No reply required.
GL
I see in this video you talk about bass absorption on the front wall. I believe in others you talked about putting diffusion on the front wall. For my listening room I had pre-envisioned (as a starting point) to put diaphragmatic absorbers in the two front corners with diffusion between them. But now I'm wondering if I'd be better off with more bass absorption in that area. I realize data will help me out when I have it. How do I determine which will be best? (I have to confess the RTA room measurement process scares me. Last time i accidentally blew my speakers causing thousands of dollars in damage).
R, Low frequency management is all about TAP (type, amount, position). You must select the correct type of low frequency technology you are going to need. Remember, there are three types of low frequency absorption technologies. This decision is based upon frequency and amplitude of the low frequency issues within your room size and volume. Amount refers to the square footage requirement of that chosen treatment and position is where to locate the technology. starting with low frequency absorption on the front wall area is a good start. Most front wall areas have high pressure issues because the speakers are close to that boundary surface. Most rooms we design have 40 - 60 sq. ft. of low frequency management technology on the front wall.
I have also found days ago that the front wall is more important than the corners; and just discovered the video now where you talk about the myth corners. Thank you for confirming my suspicions.
How much height would you say is important in relation to the ears to cover? from floor to ceiling? And to the sides?
If the axis are the important thing to cover and you are relative far from the corners, do you think abortion there is not that much worth it? Is it better to leave as much distance as possible between the wall and the absorption? As I understand it, the higher the speed, the greater the absorption, the opposite of the closer it is to the wall. Is placing the abortion right behind the speakers silly?
Well, thank you for your content Dennis
Cover 60% of the front wall and each of the other walls. Keep the treatment at least 12" above the listening position.
Hi Dennis,
Excellent video!!
Question: Where should I place the subwoofer in my room? Mine room size is: 2,60 m // 4,00 m
Thanks
Hi djalexgee
Many thanks. I have a subwoofer video coming out in a couple of weeks. Best to wait for that as it shows room placement. If you make sure you're subscribed to our channel you will get an alert when it is posted.
Thanks
cool, im curious
grtz
Is it better to place diffusion panels behind the speakers if they are planars?
G, It is one option. If you place diffusers on the back wall of planars, you should also treat the rear wall with diffusion. If you can not do both walls then absorption for front wall and diffusion for rear.
Hello Dennis, your videos are really insightful. Thank you very much for all the wisdom shared. I wanted to ask you, do you recommend any kind of fabric when wrapping the panels? Especially when using fiberglass as the absorption source. So you don't get to breathe those harmful particles it produces.
Thank you very much.
J, The particles go right through the fabric and into your lungs.
@@AcousticFields That's right Dennis, thank you for your response. I was really asking which fabric or material do you recommend when covering the fiberglass to prevent this from happening. Thank you once again in advance. Wish you a great day.
I understand that this is easy to overabsorb using acoustic foam, which will result in "dead" sound.
But my question is; is it possible to overabsorb low end using pressure activated devices? Or is it "more absorbers = better" rule?
Hi Daniel, You must quantify the low frequency issues within your room through measurements by developing a strategy that deals with the frequency and amplitude of the low frequency issues within your room. If you are over absorbing or under absorbing, you are using guessing as a tactic without a sonic strategy. Guessing is gambling. I am not a fan of either. We have a saying in our office: Don't hope - know.
Hi Dennis, I just built 4 broadband 4" bass absorbers, plan to place them in each ceiling corner of room, so they are kind of angled, they come a bit out from the corner though and leaves quite a space. is this still a good use of the panels or is placing them vertical to the corner more advisable. thank you for your time and videos. N.
M, Are these our BDA units?
Acoustic Fields nope, there punk diy Rockwood slapped onto a cheap wood frame with some kasmiri clone fabric slabs, there about 180cm x 60cm x 4 inch thick. I'm approached this project with wreckless abandon and thrown the absorbers in the corners with the attention not unlike Coltrane s mid interstellar solos to being in key. appreciate your reply sir, I can send ya a pic if necessary, cheeri-O. 🎶
M, Without knowing the frequency response of the unit, it is difficult for me to assist you. With a 4" depth and a building insulation fill, you will be absorbing from 90 Hz. and above. This unit would not qualify as a broadband low frequency absorbing device. What is your room size/volume/usage of the room?
Acoustic Fields Dennis, appreciate your time, I see, well the dimensions are 12.5x11.7x8.1ft, the speakers are currently placed parallel to the lengthier side, about 20cm from the wall with a king size matress in between. the opposite also has a 15cm width king size matress, there is also a couple of sofas. the room is for mixing and production, it would be great if I could bring it up to a level for mastering.critical listening is saught after, I'm hoping to create a RFZ (reflection free zone) for the mix position which is now almost right smack in the center of the room. sitting on the sofa in the back end of the wall opposite the sound has a huge bass boost which is almost desirable as clients can get a more home theatre vibe when listening back :) at least that's how keep positive about it,:) mix position accurate sound is what I'm going for, nothing on the ceiling yet, but I'm planning another bass absorber or two installations up there along with some fractal diffusers... live in Taiwan so not sure what materials would be available at what cost if you recommend something, cheers man, 🍻
Hey, thanks for your video! So I'm dealing with this. I have a substantial amount of low frequencies building up in the middle of my home studio (1 room, both for recording and listening). I have big superchunk bass traps in all corners. I have a big window in front of the room and would not like to cover this with bass reducing devices. Would it help to make a big bass trap all over the rear wall? I understand it's hard to judge when not having the precise measurements of the room.
L, This is a good example that putting absorption in the corners does not have the desired impact. Axial modes are produced by two walls so you must treat both offending walls.
@@AcousticFields Would it help to get a subwoofer and move this around or should I focus on the room first? Also, will 1 sub woofer be enough to deal with this?
L, It has to be a combination of both treatment and positioning. Both will lower amplitudes when used together.
And the absorbers behind the speakers should be wideband or tuned at a certain frequency (room mode frequency for example) ?
Hi Casovini, Most of the time it is more broadband low frequency coverage. We use 30 Hz. - 200 Hz. However, sometimes you need more frequency specific absorption from 30 - 50 Hz. It depends on the ceiling to floor dimension along with the width dimension. Low frequency driver number and diameter plays a part as well as their locations within the room size and volume. There is no one size fits all.
Question: Is this video only assuming a two full range loudspeaker setup? In my setup I have everything below 100hz going to a sub,, so does that mean it's lower priority to treat behind the speakers now?
+Scott smith Room size and volume are the critical factors in dealing with low frequency energy. The unwanted low frequency pressure areas manifest themselves in different locations depending on room size and volume. Fill out the information in this link and I can assist you with those issues and the appropriate treatment. www.acousticfields.com/free-acoustic-treatment-room-analysis-tell-us-room/
Dennis, is there anyway to send my room photos to you? I am getting a very bloated sound out of my PB 2000 subwoofer.
B, Send to info@acousticfields.com
Still current today?
The room only sees energy. Nothing will ever change in that domain.
nice..
The most critical spots on ceiling: where are they?
usually above the listening position and above the speakers