best room for sound

[bottleneck]

bass bins wont be built until I have a room capable of taking them.

they really are a force unto themselves.

 

[oedipus]

oedipus, I'd like to build some horn loaded bass bins .. so that wont be a problem.. but is the room good ?

..this is an example...

I just want the basics as right as possible..

The issue with big rooms (like your first choice), is that in winter you can freeze to death. I lived in a huge flat once, the living room had 12' ceiling and it was 20x25 or so, and for 6 months of the year was completely uninhabitable!

Which reminds me of this joke:

husband Get your coat, I'm going down the pub.
wife Am I coming with you?
husband no, I'm turning the gas off.

If you like to sit say 10' back add 4 feet to the front wall and back wall (so 18') and then the speakers need to be between 8 and 10 feet apart, so add at least 4' to the nearest wall, so width between 16 and 18 feet. And go for 8 foot ceilings.

A reasonable rule of thumb is avoid rooms which have dimensions which are multiple of each other (ie share a common factor) eg. 24x16x8.. It's a little bit trickier than that in practice, because depending on the construction, and the reflection/absorbtion, from an acoustic standpoint the dimension can actually be different. (Which is trivially revealed by measurement - and tools like Cara are no substitute for actual measurement).

The other thing to watch out for is large "coupled cavities" (hall ways to other rooms, or a door to a kitchen, stairways etc.) They can screw things up.

Generally symmetrical construction and layout is good too - along with as few doorways as possible (because it is sods law you'll want to put a speaker in front of a door).

Finally, that sub you're looking at is impressive, but in really big rooms, I'd expect you'd need 4. In my 20x14x8 room I have TWO 15" velodynes and sometimes it isn't quite enough (even though the velodyne is a much smaller box, that "problem" is resolved by using huge amounts of power.)

Tenson is probably a good person to help you measure and resolve slap echo ("spot treatment") and bass boom (traps). I'm a fan of using EQ to resolve bass boom.

 

[Shuggie]

With your speakers get the biggest room you can - full stop....Richard

Quite right. If you start with a big room, then almost anything can be achieved, assuming that it's not a cube and every surface is covered with marble! If you start with inadequate volume, then there is very little that can be done to make a really good listening room, and it's too easy to overcook absorption. the downside of a big room is, as has been pointed out, the power required to get a decent listening level.

Cheers

Shuggie

 

[melorib]

Without beeing paranoid, I did this choosing my last home:

1- Golden ratio, 24'x 15'x 9'

2- Concrete walls and floor

3- No wall common to a neighbour, except the ceiling

4- Isolated the ceiling with 2" cork + sheet of pladour

5- Furnished taking care to have different surfaces facing each other, like bookshelf on the right, plain wall on the left, maybe with diffuser

6- No hard surface furniture, glass or metal, heavy courtains, etc...

They say it is easier to treat a regular shapped room than one with cathedral ceiling or odd shape...

 

[andyoz]

One thing that strikes me Bottleneck looking at your current set-up is you're almost doing 'nearfield' listening with the speakers so close to the couch - direct to reflected energy ratio will be high.

If you were to purchase property in Picture 1 (for example), it indevitably looks like the speakers will be MUCH further away from the listening position than you have been used to. Have you ever listened to gear in those conditions and did you like it? I personally enjoy it but others may not and it may be a case of going from one extreme to another for you.

Having a larger room has two main benefits provided you can get enought power into the room:

i) a lower Schroeder Frequency, and
ii) speaker/listening position can be moved away from room boundaries to reduce interference effects (i.e. comb filtering, etc)

Also, what's the max. ceiling height for the room in Picture 1 - I think that photo is making it look higher than it actually is?

 

[Stereo Mic]

Number 2 Chris.

And it's worth remembering that placing your proposed loudspeaker setup in any of these rooms will make them quite cosy in reality.

If you want to hear how interconnecting areas affects the sound, come over and I'll open up the doors or block the chimney with acoustic wool. You will be surprised.

I always favour solid construction, as you can tune the resultant room gain quite easily. Lossy construction will see you adding more and more bass reinforcement to no affect. If it were me, given the investment you are making, I would model the prospective rooms in 3D on Cara and take some measurements. It'll probably take a week of hard work but ultimately will save you a lot of worry.

 

[bottleneck]

unfortunate that room '2' is the best.

I rather thought it might be. It's an amazing house in some respects (4 bathrooms! - I'll never be stuck for the loo!!)... but it's location is hideous, overlooking a rugby stadium.

With that one, I'd have to get my head around the old adage that you 'live on the inside' of a house.

I'll keep looking, just in case..

 

[bottleneck]

One thing that strikes me Bottleneck looking at your current set-up is you're almost doing 'nearfield' listening with the speakers so close to the couch - direct to reflected energy ratio will be high.

If you were to purchase property in Picture 1 (for example), it indevitably looks like the speakers will be MUCH further away from the listening position than you have been used to. Have you ever listened to gear in those conditions and did you like it?

God yeah.

My speakers sound shit right up close.

They were designed to be mid-field - and were used in their day as mid-field studio monitors, home theatre, and other applications in the mid field.

I've heard them further away in a good acoustic, and been spoiled by the memory ever since!

 

[SteveC]

There's much advice here that fits with my experience - I'd only add two things. First, stay away from L-shaped rooms (the symmetry argument - I've had a long struggle in getting a good sound in a 31 msq L-shaped room, I have a spreadsheet that will predict troughs and peaks qualitatively).

Secondly, if you have significant bass, then the bigger the better. Large rooms have many more ways to fit standing waves in, i.e., many more different bass wavelengths and multiple wavelengths fit in them, which is better because the net result is to even out the response, a bit like one would rather lie on a bed of hundreds of nails than dozens.

 

[bottleneck]

Hi Steve,

I'm guessing that wouldn't work with the vaulted/beamed ceiling of photo 1 - much to my chagrin..

 

[oedipus]

Here's a good introductory book that you should read:

Master Handbook of Acoustics
F.Alton Everest
ISBN: 0071360972
£17.15 @ amazon.co.uk

 

[bottleneck]

woo.

found a good un..

27x18, with what looks like 10 ft ceiling.

this one has french doors, and a visible archway to the dining room.

perhaps the more 'ideal' shape makes up for that however?

 

[melorib]

Very good size...

 

[andyoz]

That opening only looks about 5' wide on a 27' long wall.

Shouldn't be too bad.

 

[bottleneck]

Here is something interesting that I've just read:

" Basically, you need to look for a room with a physical long dimension of half the wavelength of the lowest frequency your monitor can produce - so for a 50 Hz monitor, you need 14 feet of room front to back dimension. A rule of thumb to remember is that every time the frequency reduces an octave, the distance needed doubles. Thus, for 25Hz, you need a 28-foot room. Here's a table to help you (in half wavelength - monitor low frequency to room):

60 Hz - 12ft 40 Hz - 16ft 30Hz - 24ft 20Hz - 32ft "

If we presume that the article is correct, this goes to show the meaninglessness of plumbing the depths with low frequencies in a small room.... or, to put it another way, your speakers may go to 30hz, but if your room isn't 24 feet long, you're never going to hear it!!

 

[Stereo Mic]

your speakers may go to 30hz, but if your room isn't 24 feet long, you're never going to hear it!!

Julian can attest to that being rubbish provided you are prepared to do your listening in the adjoining kitchen.

 

[julian2002]

or next door, or down the street or in fact in the next county....

 

[julian2002]

surely you'd still 'feel' the bass as long as it was high enough energy to vibrate your diaphragm or trousers. sound is a set of compression waves which travel out from the drivers at the speed of sound (duh) a 30hz frequency doesn't magically generate itself 24 feet away from the speakers. all you need to do to hear (feel) bass in a small room is wick it up...job done.

 

[walnut]

The rule of thumb figures are a bit out. The 27x18x10 room should be 'good' down to 21hz. Below that room distortion sets in, and you can hear it (all too well)!

For a domestic situation the 27x18x10 room should work well, though it would be best to close off the archway (e.g. double doors?).

Avoid stairwells / mezzanines / vaulted ceilings / rugby clubs (their noise) / adjoining neighbours (your noise)!

 

[oedipus]

You can't just look at a picture of a room and know what it's going to sound like..

It's like looking at a bit of kit and knowing what its going to sound like..

Oh wait