How big should a great listening room be?

[charleski]

This recent study concluded that, "the length-width ratio should be within 1.15–1.45 to get a reasonably good frequency spacing of the room modes"
Preferred dimension ratios of small rectangular rooms

As far as size goes, he points out that if the longest dimension of your room is under 8.6m (which is quite large for most domestic situations) then all the room modes will be above 20Hz. So we can conclude that in most cases (with smaller dimensions) it's the size ratio that becomes important. Of course the room needs to be big enough that you can sit a meter of two away from the speakers.

 

[antennaguru]

I'm very pleased with my main room that is 17.5' X 21.5' with an 8' high ceiling.

 

[rdenney]

what size does that translate to?

At about a millisecond per foot, a ten-foot longer path for the first reflections?

Rick "who has very few first-reflection surfaces except the front and back wall" Denney

 

[Trell]

This recent study concluded that, "the length-width ratio should be within 1.15–1.45 to get a reasonably good frequency spacing of the room modes"
Preferred dimension ratios of small rectangular rooms

As far as size goes, he points out that if the longest dimension of your room is under 8.6m (which is quite large for most domestic situations) then all the room modes will be above 20Hz. So we can conclude that in most cases (with smaller dimensions) it's the size ratio that becomes important. Of course the room needs to be big enough that you can sit a meter of two away from the speakers.

As usual, it depends on your specific circumstances. These types of calculations makes assumptions on the materials of the walls, which makes the math easier but real world application less relevant.

 

[MediumRare]

This works for me. Note, the mains are not as close to the wall as they appear, but also as close as WAF will allow. Also, MLP is an equilateral triangle to speakers 8' apart. I get very tight, non-directional bass and a precise 2D soundstage about 150 degrees. Was very easy to EQ the bass given the effective lack of modes. Would get more 3D soundstage with more distance to the front wall, I believe.

 

[eric-c]

In addition to the room nodes, there are practical considerations. Is the room for 2 ch listening only? 2 ch with subs? Multi channel listening? If MC, it may look weird if you have a very large room and 5 speakers in the "middle" of a "large" room. I assume it is a dedicated room so optimal speaker placement is not an issue whether it is 2ch or MC.

 

[Ron Texas]

pics of Goldilocks?

She looks like Scarlet Johansen.

 

[GD Fan]

Agreed that ceiling height is hugely important. Living in this gritty city ain't easy (or even necessarily recommended) but 12' ceilings make listening in an otherwise smaller space far more enjoyable.

 

[Marc v E]

Let's say you want to reduce the amount of room treatments needed, and DSP "tuning" required as well.

You are building a new room onto your house, or you are going to buy a new house.

How big should the listening room be?

It's not a matter of how big but what shape.
The sound bounces around. If you want to minimize the reflections the speaker should ideally be built in your wall and that wall be a semi circle. In that way you minimize the reflections coming to your ears.
Then the seating position should not be close to a wall again because of reflections.
At least that's the way I understand it.

In a real world application where houses and rooms are built like boxes that translates to:
* place your speakers away from the back wall and side walls. Experiment what it does with the sound (measure) and decide on the best position. In most cases 1 meter should be fine.
* place your listening seat/sofa away from a back wall.
* use subwoofer(s) and eq.
* use curtains, soft surfaces to absorb the sound to dampen a highly reflective room.

If you build a house from scratch you could do what recording studio's do:https://www.startpage.com/av/proxy-...49aa4a70d46699c7663b59a17507ff8bf4b35a2e33dd7

 

[Chromatischism]

Agreed that ceiling height is hugely important. Living in this gritty city ain't easy (or even necessarily recommended) but 12' ceilings make listening in an otherwise smaller space far more enjoyable.

I hope I can get a larger room some day. I have 8' ceilings with the Acoustic spray-on stuff applied (basically drywall mud with styrofoam balls mixed in). It sounds good to me but it's an intimate, detailed sound. Imaging is great. Almost spooky realistic how sounds catch me off-guard at times. However for multi-channel I do wish my speakers were a little more spaced out.

 

[charleski]

As usual, it depends on your specific circumstances. These types of calculations makes assumptions on the materials of the walls, which makes the math easier but real world application less relevant.

Increasing the absorption coefficient simply reduces the magnitude of room modes, but doesn’t alter their frequency spacing. Whatever the nature of your walls or room treatments, an optimal result will still be dependent on making sure the room modes are as evenly spaced out as possible.

 

[abdo123]

what size does that translate to?

Doesn't matter, as long as there is at least 3.5 meters distance between each Speaker and the closest reflective surface.

If you want sublime sub-bass then all room dimensions should be longer than the 20Hz wavelength so higher than 17.5*17.5*17.5 meters. It's cheaper to do multi-subs though.

 

[charleski]

Doesn't matter, as long as there is at least 3.5 meters distance between each Speaker and the closest reflective surface.

If you want sublime sub-bass then all room dimensions should be longer than the 20Hz wavelength so higher than 17.5*17.5*17.5 meters. It's cheaper to do multi-subs though.

It’s the half-wavelength that matters (see Toole chapter 4, particularly figure 4.21). But 8.6m is still pretty big for most people.

 

[Mart68]

Based on my experience of many different houses I reckon a room 30' by 20' by 10' (high) is pretty much perfect, Needs to be brick and concrete though, no bouncy wooden floors or reverberating walls.

Not easy to find rooms that size in this country though and a house with rooms that size would be very expensive unless it was in the ghetto, Like six figures expensive.

 

[abdo123]

It’s the half-wavelength that matters

perhaps I should have made the word 'sublime' in bold. If we're talking about absolute perfection then every wave must have the full necessary space to 'unfold' or 'expand'.

 

[Georgeadv]

In a slopped ceiling situation, where the speakers should be placed?

on the ascending or descending side?

 

[Gregm]

So my experience is that a bigger room with either proper treatment or other means to tame reflections can't be beaten by a smaller room.

I second this -- my recent experience moving from a 5.5 x 7.5m room (near ideal measurements) to a much smaller one confirms this on all counts.

 

[MediumRare]

Doesn't matter, as long as there is at least 3.5 meters distance between each Speaker and the closest reflective surface.

If you want sublime sub-bass then all room dimensions should be longer than the 20Hz wavelength so higher than 17.5*17.5*17.5 meters. It's cheaper to do multi-subs though.

So I need to live in a blimp hanger?

 

[abdo123]

So I need to live in a blimp hanger?

Thats one of the reason why concert halls are so big.

I might, but got to find it. Been years. I will try but no promises. How bad are the dimensions? There are ways to cheat the sound waves. Stacking can work and trifold standing partitions can work.

it's L shaped.

 

[Jim Matthews]

In a slopped ceiling situation, where the speakers should be placed?

on the ascending or descending side?

I suppose where you can comfortably sit determines seat placement.

I have my speakers under the sloping dormer, so it's like a horn.