There's very little going on below 30 Hz, and what is happening is definitely not musical. There might be the odd rumble.

To put it musically, the difference between 20 Hz and 30 Hz is around a semitone, the smallest increment in music (excluding music from some cultures). The only instrument capable of reaching below is a pipe organ, and even then I've heard organ music (at a decent volume) on the BeoLab 9s, and they really push out the low frequencies with lots of ease...

i like the rumble effect in movies; will the lab 9's without a sub give you this effect or do i need to use my beolab 2 as well. If i could i would buy lab 5's but i cannot justify the extra cost over the 9's- which to my ears sound really pleasant.

Does anyone know if you can set the cross-over points using a beosystem 3?

Hi Dave,

While bowing to your definitely "mountaineous" knowledge compared to the molehill I've gleaned, I'd like to draw your attention to a few things.
In your paper "Design considerations for an idealized surround sound listening space" you write that in order to achieve best possible room reflection properties:

Loudspeakers need to be at least 6' from any wall or else installed in the wall. (Bottom of page 4, top of page 5. link

In your article "What about BIG studio monitors" you touch upon the need to manage room reflections, and write as follows:

All enclosed spaces have reverberance, except anechoic chambers. Along with the concern with standing waves (which are comparatively easily managed, thank God), the placement of loudspeakers in a room, relative to walls and listeners, seriously affects the low frequency performance of the speaker in the room. There are two primary engineering approaches to dealing with this: (a) mount the speakers in the wall, so that it becomes part of the boundary of the room, or (b) place them far enough into the room that the low frequency interference problems become low enough in frequency to not be an issue. Five feet from the nearest wall would be probably minimum – I know, I know, you’ve still got the floor to worry about, but it turns out that the first null from the floor reflection is usually high enough (ca. 500 Hz.) that it can be dealt with other ways, if you want to bother.

Here you indicate a minimum of five feet - for loudspeakers in general in a listening room.
(Page 3: )
 

The above, of course, conforms well with general recommendations about speaker placement for best possible reproduction of sound in small listening rooms (such as living rooms, music rooms, etc.) Cardas and others have made similar recommendations with specific placement relative to surrounding walls.

Another matter entirely is what the room (if it's small), the room aesthetics and the opinion of others who also occupy the room will allow. BeoLab 5s are quite a dominant feature in a room and placing them "in your face" out on the floor probably takes some diplomatic skills for some.

While I'm full of admiration as to what B&O can accomplish with their speakers, I'm also non-plussed when it comes to how they show them in photography - often up against the wall in rooms with masonry walls and concrete or marble floors. Any speaker would have a hard time creating good sound in such a hyper reflective hard-walled environment. 😁 

As to the bass correction on the BL5s it's definitely an advantage, but in my opinion one shouldn't buy indiscriminately into the "will correct problems with the bass and can be placed anywhere" claim. As an owner of a pair I have been using them in different rooms, with different placement (up against walls, far out on the floor, stages in between). Even with calibration performed I find the speakers produce quite different results in bass sound pressure relative to where they are in the room. I have run bass sweeps from 0-120Hz through them, and gone hunting for dips and peaks in the signal, of which there can be quite a few when they are in the wrong place. (Even in my present listening room which is quite good for the purpose).

I am personally astonished by the Acoustic Lens Technology because of its ability to disperse sound in ways that I feel better mimic how various instruments create sound. My understanding from reading your thoughts on sound dispersion is that one should actually work with the room reflections, rather than try and defeat them totally (creating the "deadened listening booths" that some think are an ideal) - and to that end, I have followed many of your recommendations (not being afraid of featureless and smooth side walls, for instance; and even trying to point the speakers straight into the room, rather than using toe-in). 

Could I suggest something? That you actually set down your thoughts on the best use and placement of the speakers you have contributed to with your ALT design? You're years and years ahead of what any of us can figure out on our own!

I had a pair of F3 Audiovector which I loved derely, and I changed to BL9. The first month I truly missed the mid range, and had the same experience of metallic highs, and very very deep bass, but no midrange.

This does change over time...!!!!!!!   When they have matured you will enjoy the musical picture. Believe me.... They will never sound as Audiovector's but they have their own smooth picture which I trust that you will come to love over time.

 The Dane

I often find that a lot of hifi systems seem to have 'too much' midrange. I mean sure, it sounds nice and 'open', but it doesn't sound very natural. As someone who plays multiple instruments daily, I've noticed that what audiophiles in fact think is a very natural sound, is actually a very midrange-biased sound. String ensembles seem to come out worst, usually sounding really 'pushed' and harsh in the mids, wheras this never happens on BL9s/5s/maybe 3s.

Niveau,

 I am glad my ears didn't deceive me and that others have discovered it. The problem with letting the speakers "wear in" is that you don't really know what you are going to get until after you have spent the money.