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Diaphragmatic Absorber Scrutiny Needed
Old 2 weeks ago
  #61
Gear Head
 

Quote:
Originally Posted by thethrillfactor View Post
its weird comparing the latest measurement to when you had your panels, you have almost no decay at 10khz and slowly it starts to increase to around 300msec at 1khz.

So either the measurement got corrupted or maybe the mic calibration file did not get loaded into the measurement.

Looking at pictures of your place i have a better idea what's going on( when measuring for room response point the mic up 70-80 degrees not at 0 degrees).

OKay I checked and the mic and soundcard cal were included. I redid the measurements now with the mic at 70-80 deg - this is how I usually do them but in the tutorial for finding the lis position Boggy mentioned he had the mic pointing at the speaker and the pics indicated this too. but I ran over everything again and re-did the measurements (L + R) I did 5 takes of each side to make sure they were consistent. (attached)

Quote:
Originally Posted by thethrillfactor View Post
1) Your background noise is measuring high (around NR 30), now looking at picture you don't have central air, but a Mr. Slim type of unit. In quiet mode i think the best they do is an NR of about 20-25 if you are lucky. And you have it right over your speakers in the mixing area which is not recommended at all in a control room. Can you switch sides so you can have it behind you?

If not it will be very difficult to near impossible to meet the NR10-max NR 15 of the EBU Tech 3276 standard.
My neighborhood is quite noisy during the day (when the last measurements were taken) the recent measurements I did now are at midnight when it is probably the quietest around here - not sure if its made a difference. I cant move the listening position because the door is at the back left, but I could get the aircon company to come in and move the unit to the back - its not something that has been on during any measurements - its used very rarely.

Quote:
Originally Posted by thethrillfactor View Post
2) You have pitched ceilings and they look high. If the ceiling is high enough you may not need a cloud at all.
They are not very high they go to a height of about 0.8m heigher than a normal flat ceiling (3.675m floor to top)

Quote:
Originally Posted by thethrillfactor View Post
3) On your current treatment plan dump it.
First of all 4" won't give you a true broad band trap. You need at least 8" minimum with the right flow resitivity.


But if your ETC is really surpressed -20-30db in the first 20 ms, then early reflections isn't really a problem in your space( but you didn't post the Right side measurement so not totally sure).
(The 4.0ms energy spike is mostly likely from the floor).

This all contingent if its a legitimate measurement. Your Topt shows one anomaly, the Decay shows someting similar but the Spectogram is completely different.
Okay I have attached the new left and right measurements - I made sure the cal files were being used and that out of 5 measurements done on each side that they were all consistent - so this is the result of that - I don't know why that happens with the Topt? it goes down to zero at certain bands?

Quote:
Originally Posted by thethrillfactor View Post
4) Your biggest issue is the strong modal resonances(especially in the corners/front back wall) and the SBIR in the lower range that can be fixed with mutliple subwoofers placed correctly and managed with DSP.

If focusing on front and backwall focus on the 2-0-0 mode instead of the 1-0-0.
Especially if you are interested in meeting the 3276 standard which doesn't focus on bass below 40hz.
OKay thats kind of reassuring even though I was happy to attempt to trap 1-0-0 as you say below 40hz isnt considered. I think the 2-0-0 on the front and back wall is achievable. And if need be a sub can be implemented later as a solution for the 1-0-0 if its a problem.

and then the +/- 37Hz 0-1-0 mode on the side walls?

Quote:
Originally Posted by thethrillfactor View Post
5) Do you have a measurement for your monitors manufacturers showing the true Frequency response in an anechoic space? Its good to know if there are any abnormal bumps or resonances from your monitors that may show up in room measurement.
Unfortunately the manual doesn't have this - I checked the service manual and it only gives the response of the amplifier. Someone did their own test on the speaker in a review but its probably not in an anechoic space. I attached what I could find.

"Our measurements are performed using the RightMark ™ Audio Analyzer PRO software and hardware complex . The measuring microphone Earthworks M50 is also used , with passport data:

Microphone Serial Number: 92901C
microphone sensitivity at 1 kHz: 26.4 mV / Pa
uneven frequency response of the microphone in the range of 20 Hz - 20 kHz: 0.2 dB
uneven frequency response of the microphone in the range of 3 Hz - 50 kHz: + 1 / -3 dB (roll-off from 45 kHz)"

Quote:
Originally Posted by thethrillfactor View Post
Lastly for ideas with the RFZ design read this pdf from Peter D'antonio of RPG:
https://www.rpgacoustic.com/document...om-design.pdf/
Thanks for this I have gone through it briefly, I will go through it a bit more again. It was interesting to see the evolution over time and how things have changed to where they are now. Maybe I am not connecting the dots, but I wish they would go into more detail about how they go about it and the rationale behind what they are doing - its difficult to try cross apply it sometimes?
Attached Thumbnails
Diaphragmatic Absorber Scrutiny Needed-bm6a-mk-ii-specs..jpg   Diaphragmatic Absorber Scrutiny Needed-monitorampresponse.jpg   Diaphragmatic Absorber Scrutiny Needed-monitorfreqresponse.png  
Old 2 weeks ago
  #62
Lives for gear
 
akebrake's Avatar
 

Quote:
Originally Posted by Anna_logue View Post
Okay I have attached the new left and right measurements - I made sure the cal files were being used and that out of 5 measurements done on each side that they were all consistent - so this is the result of that - I don't know why that happens with the Topt? it goes down to zero at certain bands?
Possible issues?
1. Large meas.file, (96kHz sampling, 3.5 s decay time )
2. Small buffersize
3. IR Truncated after 1.7 seconds ?



Suggestions:
Delete Preferences /Shut down.
Start again with 48kHz sample rate and increase the Buffer size.
Try one sweep (instead of two)
Try change truncation in Preferences/ Analysis

Just my guess as the zero Topt ERR did not happen in the treated room measurement

Hope that helps

Quote:
...Maybe I am not connecting the dots, but I wish they would go into more detail about how they go about it and the rationale behind what they are doing - its difficult to try cross apply it sometimes?
Dr Peter D’Antonio has contributed with a number of articles, papers, slides, books since 1983 when he started RPG Inc.
AFAIK He sold his company a couple years ago (server closed).
That is probably a lecture compilation of his research/ work.
How nice it would be if we also could hear his comments to it.

More here LINK

Best
Attached Thumbnails
Diaphragmatic Absorber Scrutiny Needed-treated.jpg   Diaphragmatic Absorber Scrutiny Needed-truncate.jpg  
Old 2 weeks ago
  #63
Gear Head
 

Quote:
Originally Posted by akebrake View Post
Possible issues?
1. Large meas.file, (96kHz sampling, 3.5 s decay time )
2. Small buffersize
3. IR Truncated after 1.7 seconds ?



Suggestions:
Delete Preferences /Shut down.
Start again with 48kHz sample rate and increase the Buffer size.
Try one sweep (instead of two)
Try change truncation in Preferences/ Analysis

Just my guess as the zero Topt ERR did not happen in the treated room measurement

Hope that helps



Dr Peter D’Antonio has contributed with a number of articles, papers, slides, books since 1983 when he started RPG Inc.
AFAIK He sold his company a couple years ago (server closed).
That is probably a lecture compilation of his research/ work.
How nice it would be if we also could hear his comments to it.

More here LINK

Best
Man - thank you so much for that, really appreciate that - you guys must be double face palming every post I make, I'm sorry. Thank you for being patient and helpful. This means a lot. I'm going to go see if I can fix it now and take new ones tonight when it is quiet.

EDIT: Changed the Sampling Rate and Buffer size - Still did the same. Changed the IR Truncated to 4.4 S and seems to have fixed it. Will post the new measurements tonight. Sorry - please ignore the previous ones
Old 2 weeks ago
  #64
Gear Head
 

I redid the measurements and the the RT60 looks better now (attached)
Attached Files
File Type: mdat L Spkr - Mic Lis Pos_6.mdat (4.37 MB, 6 views) File Type: mdat R Spkr - Mic Lis Pos_6.mdat (4.43 MB, 4 views)
Old 2 weeks ago
  #65
Quote:
Originally Posted by Anna_logue View Post
I redid the measurements and the the RT60 looks better now (attached)
A question would be is why is the Right speaker driving the modes stronger than the left speaker?( You can see it in the Spectogram).

The good news is that your path to a workable space( Ebu tech 3276 compliant) shouldn't be as difficult as other places i've seen, with the exception of NR 10-15 compliance.

Your ETC is pretty clean so over treating the first reflection spots shouldn't be an issue which would effect your decay between 1khz-8khz.

2) Your main issues are:

1) Treating the corners properly for both modal resonances and modal reflections. There is a lot of activity happening in the corners. The most difficult part is how to treat the corners down to the 1-0-0 and 0-1-0 resonances.


2) Treating the back and front wall for X modal activity from 2-0-0 and up.
The back and front wall are really strong in your space.

3) Treating the sides for Y modal activity 2-0-0 and up
Your have modes X and Y modal activity on top of each other at 76hz and 153hz.

4) Treating the ceiling will be the most difficult for the 0-0-1 reflection with a pitched roof. Probably 109hz is doable as well 164hz.

By the way how far from the ground was the mic measured? This is important as it looks like it could be half way in the measurement? Between 41-48" is probably best.

Lastly is good you posted the anechoic frequency response measurement for your speakers. Now i see where the quick drop off(-6db) from 90hz to 60hz comes from and the boost between 90hz-200hz.

At first I thought it was your space, but its actually your speakers and your measurement bears that out.
Attached Thumbnails
Diaphragmatic Absorber Scrutiny Needed-screen-shot-2020-09-03-9.48.17-pm.jpg   Diaphragmatic Absorber Scrutiny Needed-screen-shot-2020-09-03-9.48.28-pm.jpg   Diaphragmatic Absorber Scrutiny Needed-screen-shot-2020-09-03-9.51.03-pm.jpg   Diaphragmatic Absorber Scrutiny Needed-screen-shot-2020-09-03-9.51.13-pm.jpg  
Old 2 weeks ago
  #66
Gear Head
 

Thank you for taking the time out to give me feedback, I really appreciate all you have done so far, really, thank you.

Quote:
Originally Posted by thethrillfactor View Post
A question would be is why is the Right speaker driving the modes stronger than the left speaker?( You can see it in the Spectogram).
I noticed that too, which made me wonder about it - I checked the speaker filters etc they were the same - I am going to try use the same speaker on each side and see if it makes a difference, I will also check the distances from back and side walls to ensure they are the same distances. Other than that I'm not sure.

Quote:
Originally Posted by thethrillfactor View Post
The good news is that your path to a workable space( Ebu tech 3276 compliant) shouldn't be as difficult as other places i've seen, with the exception of NR 10-15 compliance.
Well that is really encouraging and a bit of a relief. I think regarding the noise I think I'm prepared to live with a reasonable amount of compromise in this area. I think if I can get the room as close as possible treated acoustically I would be happy.

Quote:
Originally Posted by thethrillfactor View Post
Your ETC is pretty clean so over treating the first reflection spots shouldn't be an issue which would effect your decay between 1khz-8khz.
When you say over treating, do you mean using really thick absorbtion? 6-8"? Or the surface area? or both?


Quote:
Originally Posted by thethrillfactor View Post
2) Your main issues are:

1) Treating the corners properly for both modal resonances and modal reflections. There is a lot of activity happening in the corners. The most difficult part is how to treat the corners down to the 1-0-0 and 0-1-0 resonances.

2) Treating the back and front wall for X modal activity from 2-0-0 and up.
The back and front wall are really strong in your space.

3) Treating the sides for Y modal activity 2-0-0 and up
Your have modes X and Y modal activity on top of each other at 76hz and 153hz.

4) Treating the ceiling will be the most difficult for the 0-0-1 reflection with a pitched roof. Probably 109hz is doable as well 164hz.

By the way how far from the ground was the mic measured? This is important as it looks like it could be half way in the measurement? Between 41-48" is probably best.

Lastly is good you posted the anechoic frequency response measurement for your speakers. Now i see where the quick drop off(-6db) from 90hz to 60hz comes from and the boost between 90hz-200hz.

At first I thought it was your space, but its actually your speakers and your measurement bears that out.
The mic was 49" (1250mm) from the floor - this is my ear height in the seated position.

With the 1-0-0 mode is this something that should ignored for now and solved with a sub if needed later? Or would the 1-0-0 & 0-1-0 mode need something like a slat absorber - going back to the initial solution? If the 1-0-0 mode was to be ignored would the 0-1-0 mode be reachable with a 2.5mm steel rezonator or is this something better done with something like a slat absorber?

It seems that other than the 1-0-0 & 0-1-0 mode (ie >=50hz) is reachable with a broad band steel plate resonator like done by the BBC with 150mm of fibreglass 50% steel and 50% exposed absorbtion - and now I wonder to my self - do I treat the entire front 50% of the room (entire front wall, side walls & Ceiling) of the room like this and the back wall and the entire ceiling? Eventually I start ending up with the idea that there is a mode everywhere that needs to be treated and the room becoming a single giant steel plate resonator/absorber.

I have been trying to find some design on RFZ studio designs and I see they have splayed walls, timber frame construction in the front and back stuffed with chunks of fiberglass, slat resonators on the sides and in the back - and then I sort of wonder is this what I need to do, does the chunk fiberglass serve as trapping and are they using a certain depth for their own modes and how does this relate to what depth I would need for my situation - is there a need for steel plate then? Do I need to splay my walls too? Its difficult to try and translate from someone else's needs, room size and purposes into my own. I feel like if I had to take this approach it and someone asked why I am doing it - my answer would be "because I saw it in some other rooms"

I know I sound ridiculous but I'm not sure what is needed and where. I have the thought that it is probably a more complex combination of different devices needed in each location, to maintain balance - but I cant really think beyond my own limited knowledge and will probably end up making a mess of things going on my own advice or ideas! . Sorry for needing to be spoon fed, I know there are a lot of tools and devices to solve certain issues, I guess bringing it all together to get and maintain a natural balance is where experience and understanding comes in.

I would be interested to hear your thoughts on how you would approach each aspect of this? You have mentioned some ideas in previous posts but not sure if this would still be your approach or if there is any more or things further on this?

Do you think I should rather get a professional studio designer to come up with a blueprint/plan I could work from and work towards building and implementing? If so, do you recommend one for RFZ from the list in the sticky post? Or is this something you possibly do? Or just follow what you are saying?
Old 2 weeks ago
  #67
Gear Head
 

Firstly I really appreciate all the pointers and feedback everyone has given me over the past few weeks its been really kind of you all and has given me more understanding of what I am dealing with.....

I've thought about it a lot over the past day or so and I think I've come to the conclusion that I am completely out of my depth here. I am trying to undertake something that requires an exceptional amount of knowledge and skill (to do it right) and is based on decades of research and knowledge - Something that I simply don't have and wouldn't be able to acquire in the short term, and besides, I think its probably something that is way beyond what I would be interested in spending my time learning in any case, the amount of research, books, papers etc and I wouldn't even understand them or be able to use the information practically. And I don't think I am being fair, practical and realistic with my self.

Where I really just need the room for what I do enjoy spending my time doing, producing and listening to music!

I think this has still been a great learning curve for me, its given me a peek inside the highly scientific world of acoustics and room design and allows me to have "more" of an understanding or conversation with someone who is an expert in their field.

There are great & talented professionals out there who have spent the time, done the hours and deserve the work. I have already wasted so much time and money on ineffective advice and treatment (not here on GS but from other dealings), that getting a credible professional will be the best money I can spend and I will probably end up saving more than trying to do it my self. The amount of headaches, disappointment, frustration I have gone through over the past 12 months just isn't worth it (to me any way)

I was looking at the studio designers in the sticky post, there are quite a few there, I'm not sure which would be best for my type of listening preference - John H Brandt Seems pretty cool and the process and the way he communicates the process and his approach to things seems like it would fit in with what I need being in a completely remote location. I guess he really sold it to me the most lol and spoke directly to my frustrations haha

I would be interested to here your thoughts on my take above.... or if you have any suggestions or things to consider
Old 2 weeks ago
  #68
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Kyle P. Gushue's Avatar
Quote:
Originally Posted by Anna_logue View Post
Firstly I really appreciate all the pointers and feedback everyone has given me over the past few weeks its been really kind of you all and has given me more understanding of what I am dealing with.....

I've thought about it a lot over the past day or so and I think I've come to the conclusion that I am completely out of my depth here. I am trying to undertake something that requires an exceptional amount of knowledge and skill (to do it right) and is based on decades of research and knowledge - Something that I simply don't have and wouldn't be able to acquire in the short term, and besides, I think its probably something that is way beyond what I would be interested in spending my time learning in any case, the amount of research, books, papers etc and I wouldn't even understand them or be able to use the information practically. And I don't think I am being fair, practical and realistic with my self.

Where I really just need the room for what I do enjoy spending my time doing, producing and listening to music!

I think this has still been a great learning curve for me, its given me a peek inside the highly scientific world of acoustics and room design and allows me to have "more" of an understanding or conversation with someone who is an expert in their field.

There are great & talented professionals out there who have spent the time, done the hours and deserve the work. I have already wasted so much time and money on ineffective advice and treatment (not here on GS but from other dealings), that getting a credible professional will be the best money I can spend and I will probably end up saving more than trying to do it my self. The amount of headaches, disappointment, frustration I have gone through over the past 12 months just isn't worth it (to me any way)

I was looking at the studio designers in the sticky post, there are quite a few there, I'm not sure which would be best for my type of listening preference - John H Brandt Seems pretty cool and the process and the way he communicates the process and his approach to things seems like it would fit in with what I need being in a completely remote location. I guess he really sold it to me the most lol and spoke directly to my frustrations haha

I would be interested to here your thoughts on my take above.... or if you have any suggestions or things to consider
I agree, a full time professional is likely to save you money in the long run, or at a minimum maximize the efficiency of the spending and space itself.

I have no personal experience with John H Brandt, but based on his posts here that I've seen, he seems knowledgeable, practical, and non egoic.

Considering you have a good idea now what your looking for, and alot of the technical build is done, carpentry, electrical, hvac, your nearing the final lap.

I commend you on your willingness to get it correct. Best of luck!
Old 2 weeks ago
  #69
Gear Head
 

Quote:
Originally Posted by Kyle P. Gushue View Post
I have no personal experience with John H Brandt, but based on his posts here that I've seen, he seems knowledgeable, practical, and non egoic.
Thanks for your words. Is there a designer that you do know of or have some experience with? I understand that people may not wan't to cause a stir or try say x is better than y and its not about that. But if you know of a reputable designer who in your experience is great then I would be interested in looking into/considering them. Is there a designer well known for RFZ type rooms (in your own frame of reference)?
Old 2 weeks ago
  #70
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Kyle P. Gushue's Avatar
Quote:
Originally Posted by Anna_logue View Post
Thanks for your words. Is there a designer that you do know of or have some experience with? I understand that people may not wan't to cause a stir or try say x is better than y and its not about that. But if you know of a reputable designer who in your experience is great then I would be interested in looking into/considering them.
I have spoken with Rod Gervias a couple of times. Once for a high end home theater design/build, once for the lede studio re-build i talked about before. The home theater i had a list of questions i was "stuck" on, and the studio i had to settle a disagreement between owner and former owner about changing the orientation of the slats in the control room ceiling.

Both times Rod was decisive, picked up the phone immediately, and was extremely generous with his time, offering some good tips and a couple stories. Should i have needed his services further, i found his rates to be reasonable.

Having been self studying acoustics since 2005, and built/designed nearly a dozen studios in my region from home to commercial, i feel like ive barely scratched the surface.

Talking with Rod was a great experience, and showed me how a master would handle things. Some solutions were surprisingly (to me) practical/down to earth. Like applying coats of laquer to the live room slats until they sounded good. Lol who would have thought to use their ears!?

I intend on trying to get Rod onboard with my own personal studio in the future when i find the right new house. If you can't tell i hold him in high regard, and felt he treated me with respect despite me being "just some random kid" at the time. People around here know i frequently reference his work and forum posts, as he is well respected among his peers, and uses a data backed, approach, which is highly efficient in financial and acoustic perspectives.

This isn't to take away from the other great minds, and talented people in the field, rather just to express the personal experience I've had with a full time acoustical engineer.
Old 2 weeks ago
  #71
Gear Head
 

Quote:
Originally Posted by Kyle P. Gushue View Post
I have spoken with Rod Gervias a couple of times. Once for a high end home theater design/build, once for the lede studio re-build i talked about before. The home theater i had a list of questions i was "stuck" on, and the studio i had to settle a disagreement between owner and former owner about changing the orientation of the slats in the control room ceiling.

Both times Rod was decisive, picked up the phone immediately, and was extremely generous with his time, offering some good tips and a couple stories. Should i have needed his services further, i found his rates to be reasonable.

Having been self studying acoustics since 2005, and built/designed nearly a dozen studios in my region from home to commercial, i feel like ive barely scratched the surface.

Talking with Rod was a great experience, and showed me how a master would handle things. Some solutions were surprisingly (to me) practical/down to earth. Like applying coats of laquer to the live room slats until they sounded good. Lol who would have thought to use their ears!?

I intend on trying to get Rod onboard with my own personal studio in the future when i find the right new house. If you can't tell i hold him in high regard, and felt he treated me with respect despite me being "just some random kid" at the time. People around here know i frequently reference his work and forum posts, as he is well respected among his peers, and uses a data backed, approach, which is highly efficient in financial and acoustic perspectives.

This isn't to take away from the other great minds, and talented people in the field, rather just to express the personal experience I've had with a full time acoustical engineer.
Rod Gervias is certainly a familiar name to me, being familiar with his book and seeing his posts on here.... how do you get in contact with him? I have tried looking for his website and googled "sound solutions" but cant find anything - do you message him on here?
Old 2 weeks ago
  #72
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Kyle P. Gushue's Avatar
Quote:
Originally Posted by Anna_logue View Post
Rod Gervias is certainly a familiar name to me, being familiar with his book and seeing his posts on here.... how do you get in contact with him? I have tried looking for his website and googled "sound solutions" but cant find anything - do you message him on here?
I sent him a PM on my other stomping ground recording.org, and he sent me his number.

I believe his email is in ed2 of his book. I can PM it to if you'd like, as im not sure if he wants it out here, tho i do believe he has posted it.
Old 2 weeks ago
  #73
Gear Head
 

Quote:
Originally Posted by Kyle P. Gushue View Post
I sent him a PM on my other stomping ground recording.org, and he sent me his number.

I believe his email is in ed2 of his book. I can PM it to if you'd like, as im not sure if he wants it out here, tho i do believe he has posted it.
That would be great if you could please pm it to me - thanks!
Old 2 weeks ago
  #74
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Kyle P. Gushue's Avatar
Quote:
Originally Posted by Anna_logue View Post
That would be great if you could please pm it to me - thanks!
Sent a few minutes ago.
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