Listening in an Anechoic Chamber - a report

[Mart68]

What a waste of money to rent an anechoic to use it to compare fucking USB cables of all things.

The audiophile privilege is too much.

That was my first thought too. And they didn't even test them blind so it was a complete waste of time and effort.

 

[JJB70]

Ditto.

During the development of Silver 5L I spent two days in a 5m x 5m x 2m room (Imperial College, London). I have later tested the Silver 5L at Southampton (UK) University when they refurbished their 9m x 9m x 7m chamber (on of the largest in the UK) back in 1996.

Both were horrible experiences. Very valuable for development but for pleasure, no!

I spent time in the Southampton one, also anechoic chambers in BAE and defence establishment installations. I used to do a lot of warship design work and acoustic signature can be the most important performance metric for certain equipment so they spend frighteningly large sums getting it right

 

[LTig]

Ditto.

During the development of Silver 5L I spent two days in a 5m x 5m x 2m room (Imperial College, London). I have later tested the Silver 5L at Southampton (UK) University when they refurbished their 9m x 9m x 7m chamber (on of the largest in the UK) back in 1996.

Both were horrible experiences. Very valuable for development but for pleasure, no!

Count me in. Sometime around 1980 I visited the anechoic room of the now called KIT. It was weird and I felt a kind of air pressure in my ears, similar to when you loose height fast. It got better when the sound engineer played noise over a speaker which was not audible as such but stopped the feeling of pressure. I don't remember having listened to music though.

 

[Raindog123]

I’ve spent a lot of time in the largest anechoic chamber in the US (at Edwards AFB), and felt just fine:

 

[sarumbear]

I’ve spent a lot of time in the largest anechoic chamber in the US (at Edwards AFB), and felt just fine:

View attachment 181955

Is that an anechoic audio or RF chamber?

 

[Raindog123]

Is that an anechoic audio or RF chamber?

RF

In reality it attenuates both. But is designed, certified, and used for certain RF frequencies/signals.

 

[sarumbear]

RF

In reality it attenuates both. But is designed, certified, and used for certain RF frequencies/signals.

Do you know its cut-off audio frequency?

 

[Raindog123]

Do you know its cut-off audio frequency?

No… I could ask, but it would take a while. And no guarantee they’ve ever characterized it for acoustics.

 

[sarumbear]

No… I could ask, but it would take a while. And no guarantee they’ve ever characterized it for acoustics.

I have downloaded their manual and spec sheet. It seems it has never been tested below 100MHz.

 

[Inner Space]

There is simply no way you can build an anechoic room that works in the musical spectrum in a residential size property. You can at best achieve a "dry" room. Do please look at some examples of anechoic rooms.

Wrong, I'm afraid. My best room has ten feet of absorption on each of the four walls, and effectively more than that on 89% of each of the floor and ceiling. It's more anechoic than most research chambers, of which I have experienced many. But then, it started out 30' x 30' x 14', which is generous for a residential room, by most standards. Do please engage your imagination before you post.

 

[youngho]

Wrong, I'm afraid. My best room has ten feet of absorption on each of the four walls, and effectively more than that on 89% of each of the floor and ceiling. It's more anechoic than most research chambers, of which I have experienced many. But then, it started out 30' x 30' x 14', which is generous for a residential room, by most standards. Do please engage your imagination before you post.

Wow! So you end up with a 10' x 10' x ??? space? I can't imagine having effectively more than ten feet of absorption on most of the the floor and also the ceiling when the starting height was only 14' to begin with: 14' - 10' - 10' = ???

 

[Inner Space]

Wow! So you end up with a 10' x 10' x ??? space? I can't imagine having effectively more than ten feet of absorption on most of the the floor and also the ceiling when the starting height was only 14' to begin with: 14' - 10' - 10' = ???

Yeah, it's essentially a little listening room burrowed into a 30'x30'x14' block of Basotect, packed floor-to-ceiling over 89% of the area, hence the weird math. The 10'x10' exposed part of the floor is essentially untreated, apart from a rug. The 10'x10' exposed part of the ceiling has 2' treatment inside it, plus a thick cloud. The treatment was by far the most expensive part of the system, but honestly I think that's the best way to go.

 

[youngho]

Yeah, it's essentially a little listening room burrowed into a 30'x30'x14' block of Basotect, packed floor-to-ceiling over 89% of the area, hence the weird math. The 10'x10' exposed part of the floor is essentially untreated, apart from a rug. The 10'x10' exposed part of the ceiling has 2' treatment inside it, plus a thick cloud. The treatment was by far the most expensive part of the system, but honestly I think that's the best way to go.

That's impressive. Like non-environment taken to completion because of the lack of soffit-mounting.

 

[DVDdoug]

Mentioning USB cables gave me a "bad feeling" too... Especially since that's the 1st thing they experimented with. And then they "heard" differences... "...a more focused sound image and improved lower frequency presentation. No freekin' way a USB cable can do that!!!

 

[Hipper]

Yeah, it's essentially a little listening room burrowed into a 30'x30'x14' block of Basotect, packed floor-to-ceiling over 89% of the area, hence the weird math. The 10'x10' exposed part of the floor is essentially untreated, apart from a rug. The 10'x10' exposed part of the ceiling has 2' treatment inside it, plus a thick cloud. The treatment was by far the most expensive part of the system, but honestly I think that's the best way to go.

I would be interested to know more about this, including any useful measurements, such as decay times, ambient noise levels, frequency response.

 

[dasdoing]

My best room has ten feet of absorption on each of the four walls, and effectively more than that on 89% of each of the floor and ceiling.

all that for a private listening room?

 

[abdo123]

Yeah, it's essentially a little listening room burrowed into a 30'x30'x14' block of Basotect, packed floor-to-ceiling over 89% of the area, hence the weird math. The 10'x10' exposed part of the floor is essentially untreated, apart from a rug. The 10'x10' exposed part of the ceiling has 2' treatment inside it, plus a thick cloud. The treatment was by far the most expensive part of the system, but honestly I think that's the best way to go.

Where do you live and are we allowed to visit?

 

[sarumbear]

Wrong, I'm afraid. My best room has ten feet of absorption on each of the four walls, and effectively more than that on 89% of each of the floor and ceiling. It's more anechoic than most research chambers, of which I have experienced many. But then, it started out 30' x 30' x 14', which is generous for a residential room, by most standards. Do please engage your imagination before you post.

10' absorption on almost all surfaces in a 30' x 30' x 14' room is not what is called a residential property. Who has 14' ceilings other than in a public place? My imagination is fully engaged but your language skills seems to be less so. Or you live in a palace, then I apologise to his Lordship

 

[sarumbear]

Yeah, it's essentially a little listening room burrowed into a 30'x30'x14' block of Basotect, packed floor-to-ceiling over 89% of the area, hence the weird math. The 10'x10' exposed part of the floor is essentially untreated, apart from a rug. The 10'x10' exposed part of the ceiling has 2' treatment inside it, plus a thick cloud. The treatment was by far the most expensive part of the system, but honestly I think that's the best way to go.

I have never seen any measurements for a 360" absorber. Basotect data goes as far as 100cm, 4" and it shows that at low frequencies it is as good as transparent. Naturally there is a difference between 100mm and 760mm but still...

 

[dasdoing]

I have never seen any measurements for a 360" absorber. Basotect data goes as far as 100cm, 4" and it shows that at low frequencies it is as good as transparent. Naturally there is a difference between 100mm and 760mm but still...

40cm seams to be as good as 305

Gearspace.com - View Single Post - Basotect air flow resistivity numbers/thickness

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Multi-layer Absorber Calculator

at these thicknesses you need a much less denser material to improove:

Multi-layer Absorber Calculator

that means bascily fluffy stuff you find in pillows