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New flat has too much of sound echo

Rega

amitk777

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I have had the same problem. These new construction technologies with Concrete walls do a terrible job of sound absorption. I put in a Ikea Besta solution on one end, it helped a lot.
 

dannyarcher

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My specific question has anyone used the Nankarrow neo kit soundproofing acoustic foam kit listed at the Aural Exchange .
Thanks in Advance
Hey, I'm using the Nankarrow Neoweave absorbers and Nankarrow NeoFuse absorber-diffusers from AuralExchange to a moderately satisfactory effect. My living room also has terrible flutter echo. I put these panels on my front wall and the sound is noticeably better.

The person from AuralExchange mentioned to keep the absorber-diffuser panels on the front wall and I've had them behind my LCR.. while the sound improved, there was still a lot to yearn for. It went from unable to listen to satisfactory. I finally had time this week to relook at improving the acoustics in my room.

I was doing blind trial & error of keeping the absorber panels to cover the glass windows, beneath the painting frames but to no satisfactory effect, until yesterday.

I wondered if the absorber-diffuser panel was causing too much of diffusion which is resulting in the echo. So, I simply placed a few absorbers on the diffusers and voila.. the sound stage has improved tremendously. There is still some room for it to become kickass.. but for now, I sleep peacefully :D

Edit: Attaching the picture of my setup (here the absorbers are on their own. I now moved some of them to cover the diffusers as mentioned in the post)
 

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Nikhili

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I relocated last month to my old home in Jaipur and am rattling in what is a fairly large space. The 'music room' is a resonant space, with marble floor and a window and very little furniture at my disposal.
Egg cases can be a cheap and effective room treatment option. The ones that house 30 eggs probably cost few rs. each!
 

soundbuff

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I have had the same problem. These new construction technologies with Concrete walls do a terrible job of sound absorption. I put in a Ikea Besta solution on one end, it helped a lot.
Yes, I might bring in a bookshelf, although I don't have that many books on me right now. Unlike books CD cases won't help absorb sound. Thanks for your suggestion.

Hey, I'm using the Nankarrow Neoweave absorbers and Nankarrow NeoFuse absorber-diffusers from AuralExchange to a moderately satisfactory effect. My living room also has terrible flutter echo. I put these panels on my front wall and the sound is noticeably better.

The person from AuralExchange mentioned to keep the absorber-diffuser panels on the front wall and I've had them behind my LCR.. while the sound improved, there was still a lot to yearn for. It went from unable to listen to satisfactory. I finally had time this week to relook at improving the acoustics in my room.

I was doing blind trial & error of keeping the absorber panels to cover the glass windows, beneath the painting frames but to no satisfactory effect, until yesterday.

I wondered if the absorber-diffuser panel was causing too much of diffusion which is resulting in the echo. So, I simply placed a few absorbers on the diffusers and voila.. the sound stage has improved tremendously. There is still some room for it to become kickass.. but for now, I sleep peacefully :D

Edit: Attaching the picture of my setup (here the absorbers are on their own. I now moved some of them to cover the diffusers as mentioned in the post)
Thanks for your detailed response and the attached picture. From what I could make out the first step is to go with absorbers rather then diffusers. I could place tow rows behind the speakers (On either side of the curtains in my case) and see if that has any impact. Did you consider having something on the top corners of the walls. I was wondering if that would make a difference.

Egg cases can be a cheap and effective room treatment option. The ones that house 30 eggs probably cost few rs. each!
Yes indeed that is an inexpensive solution. May be I can try it out along with the cartons. Would these function as absorbers or diffusors or both? In any case the commercial offerings are no less ugly!
 

dannyarcher

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Thanks for your detailed response and the attached picture. From what I could make out the first step is to go with absorbers rather then diffusers. I could place tow rows behind the speakers (On either side of the curtains in my case) and see if that has any impact. Did you consider having something on the top corners of the walls. I was wondering if that would make a difference.
I did not want to do anything with the top corners of the walls for the hassle.

And yes, I'd recommend you to buy a few actual absorbers to start with. The NRC is the key. The make do stuff.. I don't know how well they absorb/diffuse.
 

Analogous

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Yes indeed that is an inexpensive solution. May be I can try it out along with the cartons. Would these function as absorbers or diffusors or both? In any case the commercial offerings are no less ugly!
Cartons spray painted would look nice too

I found this explanation online:
When sound is spreading, part of it is gradually diffused and part of it is weakened due to the absorption of air molecules over distances, this is more apparent in the open air; but indoors sound is much less diffused or weakened, instead it is mainly reflected and absorbed by the surface of materials in the room.

When sound wave meets the surface of a material, part of it is reflected, part of it passes through the material, and the rest of it is transferred to the material. The part of sound wave transferred to the material enters the pores of the material and causes the friction and viscosity resistance between the air molecules and the wall of pores, thus certain part of sound energy is converted into heat energy and is absorbed in this way.

Generally sound absorption coefficient is adopted as the index for evaluating the sound absorbing performances of a material. It is the ratio of the sound energy absorbed by a material (E) to the overall sound energy previously spread and reaching the surface of the material (E0), also called sound absorption coefficient (α). Mathematically it is expressed as:
α = E/E0
In the formula:α is the sound absorption coefficient of a material;
E is the sound energy absorbed by material;
E0 is the overall sound energy previously spread and reaching the surface of a material.
Sound absorption coefficient is related to sound frequency and sound incidence direction, it adopts the mean value of absorption to sound from all incidence directions, and the frequency of the sound being absorbed should be explicit. There are usually six frequencies: 125Hz, 250Hz, 500Hz, 1000Hz, 2000Hz and 4000Hz. Any material is capable of absorbing sound; the distinction is that their absorbing capacity is largely different. If the average sound absorption coefficient to the above stated six frequencies α is bigger than 0.2, the material is called sound absorbing material.
Most materials have some ability of sound absorption, the capacity varies. Generally, hard, smooth and heavy materials in dense structure have weaker sound absorption quality but stronger reflecting power, such as terrazzo-concrete, marble, concrete, cement rendering wall surface etc.; whereas rough, loose and soft porous materials with interpenetrated pores inside and outside have better sound absorbing performance but weaker reflecting power, such as slag wool, animal fiber, foam plastics and wood wool board etc

I also understand some degree of reflection is desirable and a totally absorbent room (anechoeic chamber types) sounds horrible (like life after death)
As in so many things science does not have all the answers it seems:rolleyes:
 

soundbuff

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That was pretty lucid, even for a non science blockhead such as I. A complete dead room would be hard to achieve in a home however so that is not our big issue. It's the marble, cement and tiles that are our headache. Since I have limited cash at hand having bought new speakers, may be I will fill up the cartons with old rags or something. Maybe punch a few small holes in their sides, and paint them to look funky️
 

Analogous

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That was pretty lucid, even for a non science blockhead such as I. A complete dead room would be hard to achieve in a home however so that is not our big issue. It's the marble, cement and tiles that are our headache. Since I have limited cash at hand having bought new speakers, may be I will fill up the cartons with old rags or something. Maybe punch a few small holes in their sides, and paint them to look funky️
@soundbuff, I look forward to hearing of your trials and discoveries. You are off the beaten path for sure.
 

Analogous

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I found these by googling “cardboard and acoustic treatment” There seems to be a rather casual attitude towards the distinctions between sound proofing and acoustic treatment though

Cardboard acoustic panels can help reduce the transfer of noise by up to 40%. They can be hung on walls, attached to the ceiling, or suspended from the ceiling to provide noise absorption away from wall areas. Those suspended from ceilings can also act as baffles to help reduce the echo within a room.’



The egg carton idea suggested by @Nikhili seems do-able after reading this: https://www.soundonsound.com/forum/viewtopic.php

And then there was this: Egg cartons don't actually help reduce sound in a viable way. They may deaden certain sounds by absorbing sound waves and frequencies, but as far as effectively reducing noise, they aren't very helpful. They also aren't the best option for insulating a room from exterior noise.

https://soundproofexpert.com › egg-...

Soundproofing With Egg Cartons: Does It Really Work? - Soundproof Expert


Your trials may reveal the truth!
 

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Analogous

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Riverbank Acoustical Laboratories actually tested egg cartons and found that Egg Cartons do, indeed, have acoustical value. They measure NRC = 0.40.
However, the graph tells the rest of the story (link below). While commercial products exhibit a smooth curve, there is a "pothole" in the acoustical road with egg cartons...
1617841814019.png
Good to remember while acoustic foam (above thickness etc) absorbs sound better than egg cartons, it does not mean it’s better for room treatment?

carpet on the walls apparently absorb high frequencies well but do nothing to lower frequencies it seems : http://www.acousticsfirst.com/carpet-acoustical-test.htm
 
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sud98

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While every substance will absorb and reflect sound, the extent to which it absorbs and reflects will depends on its intrinsic nature.

Carboard boxes and Egg Cartons have a very narrow range of frequencies that they absorb, so if thats the problem area, then please go ahead and do so.

Materials, like thick curtains, would do a much better job for a slightly larger spectrum of sound.

A big reason for your older house not echoing would be a mix of materials used (Brick walls vs Concrete) or low ceilings vs high ceilings and also the furniture and furnishings.

Average NRC is a vague and usually useless measure. Buy or use stuff which will absorb sound in the range thats relevant to you. But do all these once you have fully furnished your room, else you will be over engineering stuff.

There are enough materials NRC and absorption range data available online.
 
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