soundproof:

The risk of placing BL5s in too small rooms is that you'll know not to turn them up, but then you have people visiting, who hear what they cost, and who "want to hear what they can do." So you turn them up, and the result is quite muddled, and you begin losing confidence in your speakers, thinking they're not any good.
They are, trust me - B&O is not paying me to write this! But they need volume and a room that resonates properly to be outstanding.

I find the PDF very good. Unfortunately I have to place the speakers in the corners, and it is not a possibility to placed them facing the double door. Interesting idea though!

So I totally get the point about them needing air, but would the 9s do a better job?

I have Pentas, but I would like a bit more clarity, and 3s are to small. I have had them for a week of testing, and was missing bass. Also sometimes I am having a party, which would be to much for the 3s.

a loudspeaker between the beolab 3 and beolab 9 would be perfect!

I would listen them first before you buy them Christian

Christian:

I do not have to consult anyone on this, my strategy is: First get the speakers, then the wife....

A strategy for which you deserve applause!

But what happens at upgrade time?  Or will that include the wife also?

koning:

a loudspeaker between the beolab 3 and beolab 9 would be perfect!

I would listen them first before you buy them Christian

I have, but only in shops. I have always liked BL5 more than 9s...

I might try to talk my dealer into having them both for audition, even though he knows that I will buy second hand.

soundproof:

s/pdif over analog...

Putting a pair of BL5s inside a too small room is not recommended

Soundproof, how would I/we know if the BL5s are using s/pdif (from the Beocenter 2) rather than powerlink?

Unfortunately I think I made the mistake where my source room is too small for my BL5s and possibly too populated with furniture!

Hi Soundproof,

Great article and thanks for the tips.

However, what would be the minimum room size you would recommend to adequately accommodate the BL5s?  I live in a Victorian house and I have a dedicated room for listening and cinema viewing.  The room size is 4m wide by 5.5m long and 3m high ceiling.

I house my BL5s approx 0.5 m from the wall - equal distance from the back and side wall and symmetrical in-line.  My BL5s each sits on top of a piece of solid granite base, which is about 340mm square (the same size as the diameter of the BL5 base) and 30mm thick. I had them specially cut by my local marble merchant and I found this arrangement improves the bass quality tremendously - more focussed bass by reducing the induced bass boom since the listening room is of solid floor construction as with all Victorian houses.

For listening test, I use the xrcd produced by JVC called Best Audiophile Voices.  This cd brings out the true colour in BL5s!

KC 

moxxey:

soundproof:

s/pdif over analog...

Putting a pair of BL5s inside a too small room is not recommended

Soundproof, how would I/we know if the BL5s are using s/pdif (from the Beocenter 2) rather than powerlink?

Unfortunately I think I made the mistake where my source room is too small for my BL5s and possibly too populated with furniture!

Hi Moxxey,

The speakers auto-detect an s/pdif signal, and give that priority to the analog over PL. When I use a LINE IN connection to the speakers, and have the s/pdif attached, I can connect the s/pdif to the source (for instance my Beogram CD 6500 which has s/pdif OUT), and this signal takes over, after a half-second pause, even if the Beosystem was sending an analog signal to the speakers.

This also happens if the two signals are not the same source, it's always the s/pdif that takes presedence, as it's recognized as a "purer" signal by the speakers.

As to the second point, depending upon the furniture, it may be useful as bass dampers if the room doesn't have air. If it's all wood sticks, then it won't dampen, of course.

I think I should clarify a point. The BL5s are powerful speakers, made to deliver realistic sound levels without distortion. But if played at realistic sound levels in too confined a space, you risk overpowering it leading to apparent distortion because of room interaction, and you have to turn the music down. When that's the case, the speakers aren't working at optimum, but they're still doing a very good job. What I can say, is that the smaller the room, the more critical the placement of the speakers and listening position - and you may find it worthwhile to experiment with that. (From moving them close to walls to far out on the floor!)

KCW:

However, what would be the minimum room size you would recommend to adequately accommodate the BL5s?  I live in a Victorian house and I have a dedicated room for listening and cinema viewing.  The room size is 4m wide by 5.5m long and 3m high ceiling.

I house my BL5s approx 0.5 m from the wall - equal distance from the back and side wall and symmetrical in-line.  My BL5s each sits on top of a piece of solid granite base, which is about 340mm square (the same size as the diameter of the BL5 base) and 30mm thick. I had them specially cut by my local marble merchant and I found this arrangement improves the bass quality tremendously - more focussed bass by reducing the induced bass boom since the listening room is of solid floor construction as with all Victorian houses.

My comments about Small vs Sufficient room volume for these speakers are relative to an untreated room, where they're just plopped into place, usually because that's where it's handy to have them.

Once you begin paying attention to the principles of speaker placement, listening position, reinforcing the speaker base as you have done - thinking of where items of furniture can act as bass traps, or where a carpet can kill any secondary+ reflections, etc -- then you have begun doing things that will help the room play along better. Many of these things will help overcome the problems caused by the room being too small - and then it's a calculation between what it costs to fix a small room (in money and aesthetics), compared to moving the setup to a larger room.

The challenge is what to do about the energy BL5s generate when used at a realistic volume, whether you're listening to a solo guitar player or a symphony orchestra - and the paradox is that with an untreated and small room, where the placement is random, you may risk that the room is cancelling out the potential realism, because interference is created by the shortcomings of the room. (Standing waves, room modes, flutter echo.) Whether the room is small or large, china vibrating on a glass shelf will cause interference of its own, at certain volumes.

Here's an illustration by Ethan Winer, showing why large rooms have advantages:

It's impossibly (or insanely) expensive to counter all the unwanted effects of having speakers in a walled-in space, but the larger room provides greater volume for the sound energy to dissipate in, without creating energy "heaps". At the bottom, you see the frequency response of the smaller room going up and down in power (dB), with clearly marked highs and lows along the frequency spectrum. What's happening is that sound-waves are interacting, sometimes adding up, sometimes subtracting, creating a very uneven response where you'd want it as flat as possible.

The larger room above has similar additions and subtractions, but there are a lot more of them, the difference between high and low is smaller, and the overall effect is of a much more even response. You don't notice the highs and lows so much. So - even with room calibration in the BL5s, you could still have them in a room where the bass will be working against itself, because of the size of the room - and particularly noticeable at higher volumes, because that's when a lot of excess energy starts trying to find ways to go.

One nice thing about older houses, is that there's a lot of wood in the walls and floors, and that this can help absorb a lot of the excess energy - on the other hand, as we've seen in other threads, sometimes such rooms are so soft that they breathe with the bass pulses, taking the edge off the bass - so it's all a balancing act.

Your room is not too small. Ethan Winer (see below) would actually have wanted it to be a little shorter, to achieve an ideal room proportion of 1:1.28:1.54 - where the ceiling height is the base figure. Following those proportions, you can see that your width is quite good, and that the length is an issue.
Ideal room sizes/proportions describe a space where many of the negative byproducts of sound waves reflecting off the walls are avoided because the surfaces interact properly. Paying attention to speaker placement, where you listen, and possibly the use of bass traps, can create a very good listening space in your room.

And then, as I write below, it's also important to consider that the BL5s are a special creature - using side reflections, so you want to accommodate for those.

Ethan Winer knows a lot more about this than I do, and if you have the time one evening, reading through this will probably result in better listening: http://www.ethanwiner.com/acoustics.html#sizes%20and%20shapes

And Cardas has another, just as thorough discussion: http://www.cardas.com/content.php?area=insights&content_id=26&pagestring=Room+Setup (Note that at the bottom of each page, you can click through to the next.)

It's important to recognize that people discussing acoustics don't always agree - so don't get confused if Cardas, Winer and others don't see eye-to-eye. For instance, some of the recommendations they'll come with don't apply to the BL5s, because these are actually using side reflections to enhance the sound, where many audiophiles consider any reflection a potential source of problems.
The entire idea behind acoustic lenses is to add dimension to the sound created through them with side reflections. At any rate, the reflections that most often cause problems result from the bass - and even there, the BL5s have their own remedy: the room calibration.

So don't think you're in trouble because you have BL5s, compared to ordinary speaker designs, you're already way ahead. But you want to make certain that they're allowed to shine. Working with the room can give tremendous benefits - just thinking about what the furniture adds or subtracts will be an ear opener! (When I took all the furniture out of my listening room, it became too responsive - with too much room tone (echo). Just bringing in the couch helped dampen the room considerably towards the ideal.)

Hi Soundproof,

Just wanted to say thank you, yet another wonderfully detailed, informative and enjoyable thread!

While I may not own and or plan to buy BL5 at present, I hope that a pair of these amazing speakers exist in my future and look to putting your advice to good use.

I'm also sure that many of your points apply to other 'lesser' speakers and will assist many in setting up our rooms and listening conditions to make the most of the equipment that we have.

Thank you again,

Laurence.

Hi Soundproof,

many thanks and I certainly will read the article by Ethan Winer.  At the moment, I am very happy with the BL5 set up/configurations and perhaps, when I have more time, will experiment with different configurations to ascertain any improvements.

Very interesting ....

I wonted to buy BL8000 for years, and of course I read a lot about them and lack of bass, overpriced for their performance etc... but I could not resist. Therefore in the time of searching for speakers I was considerate to many of them but my hart was somehow always connected to 8000. I tried to listened them as much as I can, in the different shops while my business trip, and I realized that this statement was true, there was really little lack of bass. I didn't mind for that cos my interest in music is basically Jazz and Latino music.

After years of waiting I decided ( with permission of my wife :) to buy pre-owned markI from iconic-av.

One beautiful sunny day they arrived ....

I've put them on place where I previously decided to put them, turn them on and I something goes wrong .....

They sounded way better than all 8000 I've heard before ?????

Of course I was surprised, and I could not believe it how people can say lack of bass and being not warm !!!

I even went to the shop to listen again new BL8000 mark II, and of course mine sound way better !

I didn't know what is happening but I was happy.

Now I know !

After reading this thread and this PDF file about right position of speakers in the room, I realized that accidentally I've place them exactly how it was described in this PDF file !

Actually position of my BL 8000 is perfect to my room size ( distance from th walls, listening position ... )!

I tried to put them on a different position ( my wife try to kill me rearranging furniture ) and listen how they sound .... and wow ! they sound like a different speakers !!!!

So, now I realized how important is placement of the speakers ! Difference are huge !

nmartin771:

 

Now I know !

After reading this thread and this PDF file about right position of speakers in the room, I realized that accidentally I've place them exactly how it was described in this PDF file !

Actually position of my BL 8000 is perfect to my room size ( distance from th walls, listening position ... )!

I tried to put them on a different position ( my wife try to kill me rearranging furniture ) and listen how they sound .... and wow ! they sound like a different speakers !!!!

So, now I realized how important is placement of the speakers ! Difference are huge !

 

The good old "AH-HA!" moment rh? The surrounding environment of loudspeakers is indeed crucial. A basic concept of physical science. I believe it's a great thing to know; precisely why and how speakers physically work, and how we interpret sound.

I have a pair of BeoLab Pentas in a room that is 10 x 11.25 feet. How bad are these things choking? At high volumes, there is some noticable blurring. But thats blasting them. I remember seeing somwhere that the Pentas column and pentagonal box design minimized room reflections, but Im curious to see what room treatment will do. The bass will obviously get less peakey. But considering to my room constraints, will treatment help the speakers "breathe" more energy into the room or make the room sound larger? 

EYEdROP:

I have a pair of BeoLab Pentas in a room that is 10 x 11.25 feet. How bad are these things choking? At high volumes, there is some noticable blurring. But thats blasting them. I remember seeing somwhere that the Pentas column and pentagonal box design minimized room reflections, but Im curious to see what room treatment will do. The bass will obviously get less peakey. But considering to my room constraints, will treatment help the speakers "breathe" more energy into the room or make the room sound larger? 

BTW, Im using the Cardas placement method and all equalizers/boosters are off.

I believe one of the chief advantages of the Penta design was to eliminate standing waves inside the speakers - while the tall column provided for a more equal dispersion of the sound through the room - giving a greater soundstage.

Your room is near quadratic, which is usually a challenge, as there's a greater likelihood that you get peaks and valleys along the sound spectrum, as sound waves cancel out or subtract.
The best way to evaluate that is to run a frequency sweep through your speakers. A frequency sweep is a track that plays a range of frequencies - as you listen, you can determine by ear or using a dB-meter, whether the sound pressure level changes. It's quite noticeable - you'll hear the sweep frequency at what appears to be a regular level, and then it suddenly drops or rises dramatically, as it reaches a frequency where the interaction with the room is not as it should be. With square rooms, there are usually more such points along the sound spectrum.

Track 21 at this link gives you a sweep from 0-200Hz.
http://www.wavecor.co.uk/testdisk.html

You can download it to your computer, and burn a test-CD. If you want all the tracks, the link for that is at the bottom. Printing out the link-page gives you a handy reference for the tracks.

Here's a sample measurement of a room's response to sound from speakers. The surfaces are reflecting the sound energy, and the waves are interacting, amplifying or cancelling the sound, creating this jagged response curve, where the ideal is a flat one (same energy from low to high).

Great reading, Soundproof - as usual!

Based on one of the links you enclosed, I was wondering how two different approaches towards constructing corners of a room might affect its accoustics (picture enclosed).

Would 'adding corners' behind the front speakers (right picture) be an acoustical improvement or vice versa? Any experts here? :-)