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ilikesound

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Hello all! Hope all is good.

I have already posted a thread asking for help setting my listening room/closet before i got ny speakers. But when i got the speakers (Genelec 8361a) I experimented a little with placement of speakers and furniture and I think I did a pretty good job getting my room sound as best as it can (i hope). I tried as farfield as it gets and I loved how “immersive” it sounded, but it was not as detailed and crisp (is it possible to get the same accuracy and “tight/crisp” sound as in NF? and also treat the nulls in the deep bass i got in it?). I also tried nearfield- here I loved the tightness of sound but it lacked spread. To be honest I would prefer to have them very far field but i think my room is against it. I wasnt too much for production and it was always a side side hobby- so primarily for listening was the intent. But those speakers have made my rare “””production””” sessions alot more fun and frequent.

So: I want additionally treat the room with dedicated panels (not only with closets full of clothes) and here i kindly ask for help. Everything is welcome :suggestions for a better listening position, furniture placement, which panels to get and where to buy them (i am considerin ordering from Perfect acoustic- their bass traps seem really good) I will attach pictures of the room now (im also getting a sofa delivered soon) and a GRADE report of current listening position. Room dimensions are 4.26x4.26x2.5m, behind the curtains is a window.

I have seen one thread regarding horizontal vs vertical orientation of the ones and i know it should be small. But can different position of woofers in horizontal affect the bass response? I know i should test it for myself but i really dont fancy rescrewing the speakers if it should make no difference. So if anyone has any experience with doing so ill be glad to hear your insight.

GRADE Report : https://we.tl/t-xOEv3ldO6c


Thank you alot, the coffe is on me
 

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Like most rooms you have significant boundary interference and room modes below 400Hz. This also causes a significant amount of late arrival bass energy.

No, the orientation of the speakers will not impact bass response. Below approximately 1000Hz your speakers start becoming omnidirectional, and fully reach that point around 300Hz.

Yes, the Perfect Acoustic bass traps should perform reasonably well, it looks like they are using standard density mineral wool. Not the most optimized material but cost effective. Ideally you want 2 traps in each corner for full floor to ceiling coverage, the 40cm thickness membrane variety for maximum low frequency absorption.

You will want to compliment this with broadband absorption for your front wall, ceiling, and side walls if possible. It looks like they sell 11cm thickness, that should work nicely. For a room that size I would start with 3 panels on the front wall, 3 on the ceiling, and 2 per side wall.

For the side wall panels I would focus on covering the window to give more acoustic symmetry. Put the panels on rollers if you need to use the window.

Close those cupboard doors. All those open shelves are a source of significant reflection and resonance. The absorption of the clothes is borderline irrelevant. It looks like you have a bunch of cheap acoustic foam stacked in the corners, I might consider gluing or tacking that onto the cupboard doors. It is wasting space just sitting in those corners.
 
Like most rooms you have significant boundary interference and room modes below 400Hz. This also causes a significant amount of late arrival bass energy.

No, the orientation of the speakers will not impact bass response. Below approximately 1000Hz your speakers start becoming omnidirectional, and fully reach that point around 300Hz.

Yes, the Perfect Acoustic bass traps should perform reasonably well, it looks like they are using standard density mineral wool. Not the most optimized material but cost effective. Ideally you want 2 traps in each corner for full floor to ceiling coverage, the 40cm thickness membrane variety for maximum low frequency absorption.

You will want to compliment this with broadband absorption for your front wall, ceiling, and side walls if possible. It looks like they sell 11cm thickness, that should work nicely. For a room that size I would start with 3 panels on the front wall, 3 on the ceiling, and 2 per side wall.

For the side wall panels I would focus on covering the window to give more acoustic symmetry. Put the panels on rollers if you need to use the window.

Close those cupboard doors. All those open shelves are a source of significant reflection and resonance. The absorption of the clothes is borderline irrelevant. It looks like you have a bunch of cheap acoustic foam stacked in the corners, I might consider gluing or tacking that onto the cupboard doors. It is wasting space just sitting in those corners.
Thank you! is there any way to solve boundary interference and modes? I tried positioning the speakers as close to the wall as possible as well as up to 140cm from front and side wall. There are always some problems but my (noob) mind tells me that the problems I have now are actually solvable with treatment. I will order the treatment soon- starting with those pieces you recommended. Do you have any other brand I could check for treatment other than Perfect acoustics and GIK? as of now I can't really buy any 1000eur per piece panels. For the open doors I never thought it does more harm than good. I will definitely try to close them and compare the results. I know that foam isn't really doing anything but I got it for free and just put it there- do you think it could actually help if glued to the doors?

Thank you once again!
 
Short of doing in-wall speakers aka soffit mounting there will always be some boundary reflections. Those are not a big problem, just reposition the speakers so each boundary reflection occurs at different frequencies.

Room modes are the bigger concern. The corner bass traps will help with the tangential and oblique modes. Axial modes are usually too low in frequency for absorption to manage. Multiple subwoofers are the most cost effective solution, but other tools like pressure traps and Helmholtz resonators exist.

2" acoustic foam is usually useful down to 1000Hz. Reducing the srong reflection behind your head may help overall clarity. I would cover 50% of the doors, check measurements and do some subjective listening. Diffusers would probably perform better in that location but good ones cost more, and models that work down to 1000Hz are usually heavy.
 
Short of doing in-wall speakers aka soffit mounting there will always be some boundary reflections. Those are not a big problem, just reposition the speakers so each boundary reflection occurs at different frequencies.

Room modes are the bigger concern. The corner bass traps will help with the tangential and oblique modes. Axial modes are usually too low in frequency for absorption to manage. Multiple subwoofers are the most cost effective solution, but other tools like pressure traps and Helmholtz resonators exist.

2" acoustic foam is usually useful down to 1000Hz. Reducing the srong reflection behind your head may help overall clarity. I would cover 50% of the doors, check measurements and do some subjective listening. Diffusers would probably perform better in that location but good ones cost more, and models that work down to 1000Hz are usually heavy.
Thank you very much.
 
You have made a great room to work in. I'm a fan of live-end/dead-end and Hidley rooms, so my comment is from that perspective.

You already have curtains on the walls. If you extended them to 3 sides, the walls that aren't the speaker wall, you could hide acoustic treatment. Work on your floor. A decorative area rug over jute padding, not foam padding, can make the floor dead(er). You could add mass-loaded vinyl between padding layers. Make improvements and measure. After that, if you have to do the ceiling, that is harder.
 
Close those cupboard doors. All those open shelves are a source of significant reflection and resonance. The absorption of the clothes is borderline irrelevant. It looks like you have a bunch of cheap acoustic foam stacked in the corners, I might consider gluing or tacking that onto the cupboard doors. It is wasting space just sitting in those corners.

The cupboard look like they are his rear wall As such they would breaking up reflections, acting as diffusion. Possible for the better
 
If you are interested in treating the axial modes you can look into VPR traps (VPR is an initialism for something in German, so I don't know what they're actually called) but they amount to a large metal sheet attached to a piece of foam that acts as a damper. I guess large sheets of steel have a great number of resonant modes, and large thin ones even have modes in the bottom octave. On Gearspace there are threads where users have built their own and had good results.

Other than that, look into BAD (binary amplitude diffuser) panels which tend to perform better than mineral wool or foam alone in terms of low(er) frequency absorption, they also scatter sound pretty evenly, which helps the sense of space.
 
The cupboard look like they are his rear wall As such they would breaking up reflections, acting as diffusion. Possible for the better

If you consider the effective well depth and width the cupboard may act as a diffuser in the lower mid-range, such as 400-700Hz. Above that it is just a source of reflection and potential resonances.

I do agree that diffusion has value, but a diffuser design targeted at 1500Hz and above tends to provide the most increase to "spacious" room qualities without introducing compromises.
 
Based on your preferences it seems like you need quite a bit of diffusion. Especially when used for opposite side wall reflections, diffusion should work effectively down to 500 Hz area and preferably to at least 10KHz. The diffusion should also be temporal to achieve what you want.
 
Like most rooms you have significant boundary interference and room modes below 400Hz. This also causes a significant amount of late arrival bass energy.

No, the orientation of the speakers will not impact bass response. Below approximately 1000Hz your speakers start becoming omnidirectional, and fully reach that point around 300Hz.

Yes, the Perfect Acoustic bass traps should perform reasonably well, it looks like they are using standard density mineral wool. Not the most optimized material but cost effective. Ideally you want 2 traps in each corner for full floor to ceiling coverage, the 40cm thickness membrane variety for maximum low frequency absorption.

You will want to compliment this with broadband absorption for your front wall, ceiling, and side walls if possible. It looks like they sell 11cm thickness, that should work nicely. For a room that size I would start with 3 panels on the front wall, 3 on the ceiling, and 2 per side wall.

For the side wall panels I would focus on covering the window to give more acoustic symmetry. Put the panels on rollers if you need to use the window.

Close those cupboard doors. All those open shelves are a source of significant reflection and resonance. The absorption of the clothes is borderline irrelevant. It looks like you have a bunch of cheap acoustic foam stacked in the corners, I might consider gluing or tacking that onto the cupboard doors. It is wasting space just sitting in those corners.
Bass traps of the size doesn't work for the lowest frequencies unless you cover large surface areas. Only corners isn't sufficient for that. They will primarily work well above 100 Hz.

Broadband absorption as you mention is important. Specular energy should be treated minimum down to the Schroeder frequency for a very good result. That means to around 200-250 Hz in this room. 11 cm thick traditional absorbers however, will not do that.

Placing traditional absorbers on front wall is seldom a great choice since one generally want to avoid absorbing the highest frequencies there. That leads to killing late arrival high frequency energy.
 
Short of doing in-wall speakers aka soffit mounting there will always be some boundary reflections. Those are not a big problem, just reposition the speakers so each boundary reflection occurs at different frequencies.

Room modes are the bigger concern. The corner bass traps will help with the tangential and oblique modes. Axial modes are usually too low in frequency for absorption to manage. Multiple subwoofers are the most cost effective solution, but other tools like pressure traps and Helmholtz resonators exist.

2" acoustic foam is usually useful down to 1000Hz. Reducing the srong reflection behind your head may help overall clarity. I would cover 50% of the doors, check measurements and do some subjective listening. Diffusers would probably perform better in that location but good ones cost more, and models that work down to 1000Hz are usually heavy.
Multiple subwoofers don't work for the most sensitive bass area and lower mudrange, thus it should always be complimented with treatment for this area. It's not necessarily the most cost effective solution either, that depends. If one had enough space area (probably not the case her) we can achieve a very linear response and great time domain behavior for the cost of a about one or max two subwoofers.

Using 2" absorbers does not achieve a good result because they only work for the higher frequencies. Meaning the rest of the spectral content will still give high gain reflections. This simply lead to a dead result with very uneven time domain behavior.

Placement of treatment for specular energy should be surgical, not just covering a percentage. This way we preserve the energy we need to preserve in order to have a room that gives us the important ambience, psychoacoustic clues, and avoid deadening the room too much.
 
If you are interested in treating the axial modes you can look into VPR traps (VPR is an initialism for something in German, so I don't know what they're actually called) but they amount to a large metal sheet attached to a piece of foam that acts as a damper. I guess large sheets of steel have a great number of resonant modes, and large thin ones even have modes in the bottom octave. On Gearspace there are threads where users have built their own and had good results.

Other than that, look into BAD (binary amplitude diffuser) panels which tend to perform better than mineral wool or foam alone in terms of low(er) frequency absorption, they also scatter sound pretty evenly, which helps the sense of space.
VPRs are sold as Modex Plates. They work very well, but as always: To treat frequencies below 100 effectively one need several. While two can work very for a frequency at 70-80 Hz, a minimum of for four is needed for 40-50 Hz, etc. I've seen several DIY attempt that have failed. On of the reasons is that material needs a certain stiffness to vibrate.

It's true that BAD panels work lower in frequency than traditional a absorbers. However, the scattering the flat BAD perform can result in audible specular energy. This needs to be avoided either by placing them correctly or use the improved curvature BAD Arc where the scattered energy is not in phase.

BADs are still much closer to an absorber vs a pure broadband diffuser in hard material in regards to maintaining energy.
The Broadsorbor works even lower in frequency than BADs with similar thickness BTW.
 
Multiple subwoofers don't work for the most sensitive bass area and lower mudrange, thus it should always be complimented with treatment for this area. It's not necessarily the most cost effective solution either, that depends. If one had enough space area (probably not the case her) we can achieve a very linear response and great time domain behavior for the cost of a about one or max two subwoofers.

Using 2" absorbers does not achieve a good result because they only work for the higher frequencies. Meaning the rest of the spectral content will still give high gain reflections. This simply lead to a dead result with very uneven time domain behavior.

Placement of treatment for specular energy should be surgical, not just covering a percentage. This way we preserve the energy we need to preserve in order to have a room that gives us the important ambience, psychoacoustic clues, and avoid deadening the room too much.
Thank you for your input.I still don't know with what to start here?would you mind giving me a few guidelines, maybe even a store where I could buy those products?Did you check the GRADE report?

Have a great day
 
Thank you for your input.I still don't know with what to start here?would you mind giving me a few guidelines, maybe even a store where I could buy those products?Did you check the GRADE report?

Have a great day
Where to start depends on your budget, and what you can practically do. I'm assuming you can't do serious bass trapping since this takes up much space. Therefore I would suggest treating high gain reflections with broadband absorbers and some diffusers if your budget permits it. One could consider doing some treatment for SBIR as well (see example below). For the lowest frequencies, EQ can work ok in regards to pulling down some peaks.

Here's an example of the effect of Broadsorbor for SBIR treatment.
No treatment:
Frekvensrespons før og uten sidetiltak.jpg


Notice the 120 Hz cancellation.

Treatment with only two Broadsorbor panels with dimension 150x80x10,4 cm. Most of the dip is gone now.
Frekvensrespons med to stk Broads 150x80x10cm.jpg


Two smaller panels with dimension 120x80x10,3 cm gave us the result below. Not quite as effective since it didn't cover that much surface area.
Frekvensrespons med to stk Broads 120x80x10cm.jpg


I would recommend Broadsorbor/Broadsorbor Plus and Modffractal diffusers if there's a budget for it. I'm a retailer for those products FIY.

The link to the Grade report has expired. But we do know how speakers will achieve in this type of room and where you will have reflections.
 
hello.

Here is a reupload of the Grade if it helps https://we.tl/t-uJWXjhSAw4

Except for the 120hz cancelation im actually pretty satisfied with the response and i think reducing the reverberation times is the main goal here. It should make a big difference i think. Even though the room is small and the low frequency response is not the worst- do you think low end decay times cannot be improved?
thank you
 
hello.

Here is a reupload of the Grade if it helps https://we.tl/t-uJWXjhSAw4

Except for the 120hz cancelation im actually pretty satisfied with the response and i think reducing the reverberation times is the main goal here. It should make a big difference i think. Even though the room is small and the low frequency response is not the worst- do you think low end decay times cannot be improved?
thank you
The response is good after EQ has been applied, but we can also see in the report that the EQ doesn't solve the issues in the time domain behaviour. Treatment works for both the amplutude and time domain, and that's why it's better.

Either way, it's more economically to focus on the area above 80-100 Hz region. And yes, the time domain behaviour with decay time can be improved and this will help a lot. If we first take a look at refletions above the bass region, we can that there are some high gain reflections that should be reduced. - 20 dB is a minimum goal IMO, and -30 dB is ideal for a stellar result. But that doesn't mean all reflections should be reduced that much. This is very psycoacoustics come into play and where diffusion is often better.
Right speaker ETC.jpg

Left speaker ETC.jpg


Treatment placed at reflection points will lower the reflections, but it's advantage that the treatment is high effective at least down to 250 Hz area. Diffusion will not go this low, but still can be preferable at specially the rear wall and opposite side wall reflections.

The Grade report talks about the reverbertion time but this is not really accurace as true reverberation cannot exist in such a small room. However, we can look at either the waterfall or wavelet and see resonances and and long decay. Here it's evident that the EQ applied doesn't reduce the resonances and ringing in the lower region. But again, treating this may not be a good solution as it requires to cover fairly large surface area for a good result.

Right waterfall.jpg


Right waterfall.jpg
 

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