The Advantages of Floor Coupled Up-Firing Speakers

Quote:
...
"I have very wide dispersion speakers in a very wet, large room."
...

That "large room" seems not to be the typical living room, which has to
suffer from low modal density and Schroeder frequency rather high.


The eigenfrequencies of an acoustical small room form a kind of subset
of those in a large room.

The auditive small room behaviour could be simulated using
a prepared reproduction system while listenening in the large
room easier than doing it vice versa. No ?


In the example you mentioned, the excitation of mirror sound sources
might have worked well, because distances (between speakers and walls)
were large enough. Modal density was quite high, so the room created
"ambience". But that is an idiosyncratic and subjectively reported example.
Though interesting and believable IMO.

Kind Regards
 
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We don't know enough about our hearing in order to objectively define optimal sound reproduction. On the other hand we have fully operational sound reproduction techniques.

You should add various and diverse fully operational techniques

some of them are more popular, mainstream, and some less popular, and some even considered weird by some

but popularity is no criterion for reasonableness

That's probably why Bob does not agree with the soundstage of speakers with low directivity. Did you already ask him about his post at Gearslutz?

well, the quoted opinion from Him was posted "27th October 2007" as last post in now probably dead thread
in additon Bob Katz is not a gearslutz frequenter, His last post is from "20th November 2009", I would not expect to be given any answer
 

You gotta be kidding ;)
who am I to expect an answer for such a highly abstract question about over 2-years old internet comment from such a busy man?
Myself I would consider such a person sending an e-mail with such a question a maniac.

besides it is not interesting why He wrote but how He wrote it - not "I dislike such imaging and soundstaging" but "I disagree with such imaging and soundstaging"

How can one disagree with a phenomenon? :confused:

On the other hand myself I would consider asking directly such a question the person concerned simply impolite.
 
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That "large room" seems not to be the typical living room, which has to
suffer from low modal density and Schroeder frequency rather high.

well, yes, but the crucial point is that He maintains that:

it should get better in small rooms

The auditive small room behaviour could be simulated using
a prepared reproduction system while listenening in the large
room easier than doing it vice versa. No ?

I don't know, but Dr Mouton says:

DRM: No, it should get better in small rooms.

the room created
"ambience". But that is an idiosyncratic and subjectively reported example.

it was not only ambience but also "holographic imaging" (another subjective opinion) and also precision and it is not only "idiosyncratic and subjectively reported example", there are more examples and people are making control rooms according to some theoretical assumptions and those control rooms work

another idiosyncratic and subjective report from gearslutz:

I've spent the past few hours listening to music without my usual early reflection absorbing side panels. I have to say it's an interesting experience. Everything certainly sounds wider, though a sum to mono is still a very small point in space in front of me. The really interesting thing is that great recordings still sound great, if a bit more open, but mixes that were on the edge of being too strident or brittle are unbearable. That could make it a hard choice to live with for the long term. OTOH, a good monitoring system is supposed to reveal problems

this approach is just less popular but it doesn't follow that being less popular it is as such not "reasonable" and only "idiosyncratic and subjectively reported" either that those more popular approaches are in contrast "reasonable" and not only "idiosyncratic and subjectively reported"


they are just traditional and believed to be reasonable
 
Quote:

"One major loudspeaker designer had to check that the center speaker was off, because in 2-channel stereo the imaging was so good that he couldn't believe he was hearing a phantom."

I assume even loudspeaker designers and recording engineers
to be (mostly) human beeings.

The optical presence of a center speaker is sufficient to distract
our hearing. Experiments in spatial hearing show, that the
presence of an optical stimulus may well overrule acoustic
clues for locatedness of a sound source.

Our visual system is the leading system when judging
the position of objects in those cases where optical and
acoustical stimuli are present. *

That is why i do not rate that cited occurence too much in its
relevance to spatial sound reproduction.

For making conclusions about spatial hearing one needs
very controled conditions and a minimum amount of test listeners.

To have optical stimuli out of the test setting is essential.


* That corelates to why large speakers with shiny surface or expensive
veneer always sound better. Never observed ? ;)


Kind Regards
 
Quote:
"
I've spent the past few hours listening to music without my usual early reflection absorbing side panels. I have to say it's an interesting experience.
...
"

I have no problem with that.

1. We all have to change things sometimes, otherwise live gets boring.

2. Is an absorber always an advantage ?

If the absorber is very frequency dependent (usually it is) the reflected
sound from that particular wall may be a more (spectral) likely copy
from the original without the absorber.

Brain has to integrate the reflection on a hard surface:
"Aha there's a wall". Nothing unusual.

If there is a frequency dependent absorber our brain has more to do,
to form a "coherent" picture of the environment.
More effort = less fun.

Simplest way is to avoid the reflection.

In an average listening environment a constant directivity loudspeaker
causes reflections to be of similar spectral content like the original sound.

The exercise from Linkwitz i posted before goes into that direction.

To me by the time it is not so important whether a speaker has narrow
or wider dispersion. Although i prefer some directivity, to me it is more
important, to have no sharp discontiuities in angular dispersion
depending on frequency.

If that is given, you can prepare the room by placing
absorbers to achieve wide band absorbtion.

But given e.g. a 2 way speaker with 20cm Bass and 2cm Tweeter
near a side wall, any HF absorber on the side wall will alter the
spectral content in the whole listening room over proportional.

Kind Regards
 
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this approach is just less popular but it doesn't follow that being less popular it is as such not "reasonable" and only "idiosyncratic and subjectively reported" either that those more popular approaches are in contrast "reasonable" and not only "idiosyncratic and subjectively reported"


they are just traditional and believed to be reasonable

That's correct and Toole argues that additional lateral reflections are preferrable for recreational listening - even for professionals. But again you have to ask what reality looks like. Only few engineers use different control rooms for recording (critical listening) and mixing (make it sound "right" so the recording "translates" well into any listening room). I doubt that anybody is capable of rating how a recording will sound like in various domestic listening spaces while mixing in a quasi anechoic "non-environment" control room (worst case). As a result the recording is made for the control room acoustics and not for any other space.

That expands the discussion to another interesting point: music changes with the space it's played in. Church music, music for concert halls, music of cultures living outside. So "realistic sounding" might not be stereo's purpose at all.
 
Unfortunately mastering affects the spatial attributes heavily. Adding compression and all sorts of "esoteric" effects has become standard practice.

Maybe it's these effects I dislike about some "synthetic" recordings. Can you tell me some studio productions that in your opinion are very high quality in terms of mixing/reverb and purist in terms of mastering? No hit-parade stuff, please.
I prefer testing to citing books.;)
 
Do mastering engineers have any influence on what we are talking about, other than contributing their opinion? Most of us will never have the chance to listen to a track before and after mastering, but I can't believe it has any influence on imaging.

Yes.

Compressors can squash the depth out of recordings or bring them to a nice coherent pleasing level depending on how it's used or if it's needed in the first place.

EQ will have an effect on depth of the recording as well. If all they are thinking about is filling in the spectral content often you will hear recordings depth of field squashed out by high end boosts. As a sound gets further away there will be less high end and less bass generally.

MS Processing can be used which can even out the spaciousness or distort it.

It's hard to say that these things are bad exactly though. They are just tools. Dry unprocessed recordings can seem less realistic and basically underwhelming imo.

Problems in the control rooms can have an effect on the end recording as well. If the control room attenuates the way the high end is perceived this will show up as the inverse in the end recordings - overly bright spectral balance. This is the same for any other thing that the engineer is trying to control. If the room exaggerates the ambiance then the end recording might end up too dry or vice versa.
 
Hi Tinitus,

even though mostly wave guide designs with narrow dispersion
are referred to as "Constant Directivity", there are more
techniques capable of a more or less frequency independent
directivity (in a certain frequency range). Even wave guides
cover only a certain bandwidth.

An well working omni-source is in fact a constant directivity
source. In my understanding the term means directivity to
be independent from frequency nothing more and nothing less.

Even a "Wide Dispersion" system can be "Constant Directivity".

There are dipole OB designs of appropriate driver and baffle sizing
which meet the criteria quite well, also semi open bass and midrange
cabinets with kardioid dispersion.

As i mentioned before also distributed mode loudspeakers can
be made "large bandwidth constant directivity".


Kind Regards
 
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