Is a "dead room" the ultimate room?

Hi-Fi Corner
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Is a “dead room” the ultimate room?

Before discussing the “dead room” problematic we should establish what a perfect listening room is.

The answer to that question is both simple and extremely complex.

The perfect room would be a room with no boundaries, no walls.

Having walls results in interactions between direct sound (from the speakers) and reflected sound (from the walls).

In short, what you hear not only is what your speakers fire at you. And that’s bad.

Direct sound + Reflected sound = problems.

So yes, the perfect room would be no room at all.

Three options:

  • Place the HiFi in a large back yard (no walls)
  • Headphones (nearly no walls)
  • An anechoic chamber (no reflection capable walls)

The two first options are nice, but not for a speakers based system.
So what about the anechoic chamber?

Well, building an anechoic chamber is both complex and extremely expensive.

More importantly, we mammals aren’t designed to live in a reflexion free environment.

I won’t rephrase psychoacoustic textbooks; we all can access them online, or buy them (I did).

In short we don’t feel well in a reflexions free environment. We need at least some kind of hard floor.

That leads us to a so called “over damped” or “dead” room.

But what’s an “overdamped” or “dead” room?

Those expressions are often used but probably not well understood.

A “dead” room is a room that over absorbs, or doesn’t reflect, frequencies within the 1800Hz-5000Hz range, and above of course (medium driver and tweeter).

The unpleasant feeling we experience in such a room is the result of an inadequacy between what we see and what we hear.

Now my point :

Most of our listening rooms aren’t designed for music replay. In fact, most of our rooms are simply horrible from an acoustic point of view.

So why not “over absorbing”?

Not only the sensible 1800Hz-5000Hz range, but everything from 70-80Hz up to 20kHz. That would be possible with a lot of “broad band traps” (wrongly called “bass traps”).

Such a room would feel (not sound) rather unpleasant, a least for us mammals.

But …

…when hitting the play button, we would get the sound from the speakers, and speakers only, which is what we all wish we could have.

Unpleasant room when silent, perfect room when playing music

So why not a "dead room?"

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The elephant in the (dead) room, is that most speakers are designed and voiced tailored to common room anomalies.
Getting the room alive enough to sing along in a pleasurable way is a positive in my book. Although, your welcome to throw my rule book out the window - as long as you don’t have some big gubbins box in the way.

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They are indeed tested in common (but treated) listening rooms, but measured in nearly anechoic chambers. That’s true for Magico speakers, but for other brands as well.

Some Naim speakers were designed to somewhat accommodate small rooms (close to wall placement). A few other brands do that as well.

But I believe that most speakers (high performance or not) are simply designed to sound good.

There is no such thing as a standard, or common, living room. Each room has its own frequency response. It’s impossible to design a “one size fits all” speaker.

Of course, I share your opinion here.

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Yes. And, if finding that your room has troublesome nodes - that doesn’t mean every speaker will excite them. But you probably know that for sure.
Just saying some speakers will fit better in a dead room and others better in a common room usually found within that buyer of a specific model.
Some designers really have their finger on the pulse and get it right. A certain buyer for a product should have x and y in place for it to function properly.
Others of course could take a more universal approach.

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Very definitely a completely dead room would be unpleasant when not playing music. What it would be like with a stereo hifi system I don’t know, but I guess probably odd because in nowhere that you normally hear music is it completely devoid reflection, and although the front image should be perfect, I suspect that the deadness from sides and rear would make it seem very unnatural.

As I’ve recounted elsewhere the best I have ever heard any system sound was my own, lesser system compared to now, when I played it in the garden. There would have been some reflections from ground, vegetation, and wall of house some way behind, but very minor compared to the direct. At the same time there was ambient background noise of a garden, so ears relaxed.

So I think something near to dead, but definitely some ambient sound, requiring a degree of reflection, also adding slight reflection with music (but diffused not as an echo).

That is with stereo. And I suspect requires good ‘clean’ speakers as deficiencies such as significant colouration might be ome more noticeable without the muddying effect of room. Surround sound is a different matter, the ambience provided for you so might be exactly like in the concert hall in a dead room.

(Link to garden experience detail: What's the best-sounding system you've ever heard? )

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I don’t know about the science, but a friend of mine has a studio. .You can hear everything, but it’s not pleasant to listen to music in. Guess that’s what’s meant with a dead room.

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An attempt to explain the “science” behind it for anyone in the thread that may be interested. Forgive any obvious comments…

Sound is a wave. We like to see it as a curve on paper but actually it is a series of compressions and less dense areas of air particles.

But they function just like curved waves as you see in a rope you attach to something and when you give it a shake you see a curve run down the rope. But when it hits the end it reverses and comes back on the other side of the tope. It reverses the amplitude of the wave.

Same with sound when it hits a wall. It comes back with the peaks of the sound waves reversed.

When hitting other sound waves coming from the speakers what happens is that peaks in the wave will become larger if on the “same side of the rope” and cancel each other out if opposite. So a sound wave hitting a wall will perfectly cancel the exact same wave coming towards the wall. It’s called constructive and destructive interference.

So if the peaks increase each other you have a hot spot in the room and if they cancel you have a dead spot.

If the wave bounces off of something at an angle it reflects at an angle and can no longer have such a great affect on the incoming waves. That’s why sound rooms have all the weird shapes to reflect the waves.

In effect a normal furnished room does a pretty good job to disperse the waves while an empty room without sound boards sounds horrible.

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What was the particulars of your surrounding growth ?
Low shrubs ? Bramble ? Light petals or more sturdy ?
What was the moisture levels in the soil ?

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Listening to Steve wright Sunday love songs from the radio in my bathroom always sounds awesome, regardless of room effects.

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If you could go back in time and listen to David Oistrakh or Chopin playing their instruments in a medium sized room. Would you be worrying about the possible reflection/damping from windows and walls. I doubt it.

Musicians usually play and people listen to them in rooms.

And would you be pondering if filling Chopin’s piano with lead shot or sand, wittling the legs of his piano down to thin spindles and placing some oversize frame cups/ball bearings under the piano legs would bring any significant sound quality improvements. I’m sure some people would. :grinning:

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I detect a certain frivolity in the question, but:
One side 9ft tall dense Leylandii hedge 3ft deep, with 3ft high brick wall behind and beyond that mainly lawned neighbour’s garden. Other side assorted deciduous shrubs hedge about 3ft deep and 6ft high dense enough not to be transparent, with a lilac tree standing taller, no wall and again mainly lawned neighbour’s garden. Maybe 8ft average depth lawn in front of speaker patio, then vegetable/ flower bed with assorted veg and shrubs, mostly 3ft tall or less apart from runner beans at one side parallel to hedge. Then lawn again to listening area and all the way to patio against the house. 2ft wide concrete path alongside hedge both sides. IIRC had been dry for several days, certainly lawn not soft/muddy, but not baked either (not damaged by later visitor footfall).

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And recordings of performances in rooms capture the ambience - then are replayed in often smaller rooms (at least in Britain), and generally without the absorbent nature of a large group of people.

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Having done a dead room before I can say it is awful for music. It’s like being an ant trapped between massive headphones. The imperfections in a room are what give you the “live in the room feel”. The trick is to just take the edge off the problematic extremes.

Dead rooms are, conversely good for surround sound. Consider this: the purpose of surround sound is to remove the room and put you where the action is. The purpose of stereo is the exact opposite; to put the musicians in your room.

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I wonder if the room need some acoustic treatment in that case ?

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If I had to choose between this :

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Or that :

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I would choose the first to really enjoy the music in a lively not dead room.

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I think a bit of the problem here is that people talk of a ‘dead’ room and assume lots of acoustic panels , or they see a picture of a well treated room and assume its ‘dead’.

‘Well treated’ and ‘dead’ do not have to go hand in hand. To get a well treated live room you have to use the correct panels , in the right quantity and in the correct position.
Just sticking up loads of full range panels will give a dead sound.

If imperfections in a room give a ‘live feel’ then that is a room sound signature that will impinge itself on whatever you play , be it a studio or live recording.
I personally don’t want to put the musicians in my room , i want to be put in the recording venue with the musicians , be it studio , concert hall or outdoor event.

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On one of the LP/Cds recorded by Mike Valentine on his “Chasing the Dragon” label he demonstrates the difference between a small group recorded in a church and the same piece recorded ourdoors. Without feretting out the LP to check it does sound most odd when recorded in the garden, very diffuse, whilst the church acoustic is just “right”. Music is composed to be played and recorded in a room of appropriate size to the musicians involved. The exception being Handel’s Water Music perhaps?
A dead room or in extreme, an anechoic chamber sucks the life out of the music. They are used by loudspeaker manufactures to evaluate their products. KEF in Maidstone have one I think.
Which brings us back the ideal listening environment. A room with a degree of damping; not too much and not too little. All part of the fun of hi-fi!

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I suppose in reality there is no universal ideal listening room. Everyone will have their own requirements/likes/dislikes as to what they want to achieve.

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And the view

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