well, perhaps in most cases that's the fact
thanks for this "some can identify"
I believe that it can be made better, but yes, perhaps it is not an easy-and-for-all solution as I once thought
a note to the readers: with the exception of the sound-coming-from-the-floor experience:
You're not quite following - say the speakers are 8 feet apart, and you stand 2 feet to the right of the position of the right speaker - you're now standing 6 feet to the right of the centre line between midway between the speakers and the normal listening position. Where the sound subjectively is now imaged is along a line 6 feet to the right, and parallel to the centre line; it is not coming from between the speakers, nor from the right hand speaker 2 feet to your left. If you walk sideways now to beyond the left of the left speaker, the image will track with your movement, to beyond the left speaker.
No. I'm relating experiences, and this for me to date is the most likely explanation that I've come up with. Why the quality factor is critical is very obvious, because this 'effect' collapses once a nominal level of distortion intrudes - which is why the number of people who experience it is relatively small ...
interesting, what kind of distortions exactly? harmonic? IM? spurious resonances? diffraction?
all studies known show that human vertical sound localization ability is generally poor
perhaps FCUFS is not for all but - as example of our Colleague Elias shows - the conventional stereo isn't for all either
but ambience and ASW are two different kinds of spaciousness
A "real ambience" can be extracted theoretically but who does it in practice?
And I doubt that a realistic ASW can be generated with any surround or rear speakers.
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Probably what you'd term IM -- the hardest distortion to entirely eliminate is that which corrupts low level, high frequency detail in the signal - this is either largely lost, or has harsh, unpleasant overtones introduced, in both cases it's too hard for the human hearing system to decode.
This is easily heard when one puts on a 'difficult' recording, and then listens closely to the tweeter driver: this should be clean, easy to listen to - if it sounds a mess, or even somewhat unpleasant, then there's your problem ...
as IM products would be more audible on and near the axis of a distorting loudspeaker driver then perhaps there is also an advantage of using the off axis sound?
Yes, exactly. In a number of experiments people have positioned speakers in odd ways which subjectively has improved aspects of the sound, and I suspect strongly that this is part of the story there also.
I do somehow
It is expected that the 'real' ambience is recorded and is mainly contained in the L-R signal.
An externally hosted image should be here but it was not working when we last tested it.
I do somehow
It is expected that the 'real' ambience is recorded and is mainly contained in the L-R signal.
Expected according to some theory? What theory?
And what about ASW cues? Are they contained in the L-R as well? According to the same theory?
Graaf,
Still it wasn't that sound sources were all over the place (as one user described his FCUFS experiments) and I am very glad to hear that.
It could be not as much a matter of an individual high sensitivity to vertical localisation cues as of a professional (over)sensitization described by Toole in His book...and because of this sensitization You can hear things in a way others cannot.
as Dr Toole put it: "Audio professionals may have their own preferences - it’s all right, they are just different"
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Originally Posted by weltersys
"Of interest, turning the listening chair around so my back was to the operating speakers gave an inverted presentation, the general soundstage appeared to be elevated to near the ceiling, though instruments with little high frequency still sounded like they were behind and below."
very strange!
Looking on the bright side it was neither a very garbled wash of sound (as one user described His FCUFS experiments)
thanks again for taking Your time!
You're welcome.
I appreciate you attributing my locational ability to my being a professional sound engineer, but I just did a locational test with my girlfriend who is a nurse by profession, and blindfolded she could easily point directly to a sound source from any point above, below, or left and right of her.
By directly, I mean within a few degrees.
After the test I commented that she got much better after the first few tries, she replied, "I realized after you moved the noise you wanted more than just a general direction".
Hundreds of thousands of years of selective evolution has encouraged precise directional location both as a danger avoidance mechanism and aid to live prey capture.
The shape of the pinna gives better vertical azimuth perception to the front, but reduces HF sensitivity to the rear. The suppression of rear HF also gives a locational cue, more muffled sounds can be assumed to be rearward.
In the case of the FCUFS speaker at my back described in post #2811, the direct HF perception was slightly less than the first reflection off the opposing wall, giving the impression of the sound generally originating from that direction, while lower frequencies still were sensed from the source behind and below.
As far as others reporting "a very garbled wash of sound" from FCUFS, my test was done in a fairly "dry" room with relatively short reflective path lengths at thee listening position.
In a larger, more reflective room with longer reflective path lengths and a more distant listening position, I have no doubt that I'd also experience "a very garbled wash of sound" from FCUFS.
Art
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Did I say theory ? In practise !
There are very few anechoic recordings available. Most recordings contain some 'ambiance', and if recording venue cannot provide it it comes from processor.I think ASW can be generated by multible front speakers. You really should try matrix stereo
Another method to generate ASW is by frontal early reflections, and for this reason I don't like to absorb the wall in front of me.
Sound coming from two pin sized locations spaced apart and no sound from anywhere else in the front sounds very unrealistic and unpleasant.
- Elias
c'mon! such an anecdotal evidence against scientific studies?
hundreds of thousands of years of selective evolution notwithstanding all studies show that human vertical sound localization ability is generally poor
therefore science speaks not about precedence effect in the vertical plane but just about localisation dominance
besides it were hundreds of thousands of years of selective evolution without any reflective ceilings
but it is not a matter of the pattern early reflections, it's a matter of the level of late reverebration
I have no doubt that in a big bathroom You would also experience "a very garbled wash of sound" even from Your regular speakers.
Did I say theory ? In practise !
in practice You can hear something but that's it - without some theory You cannot explain and You cannot reasonably expect that anything is contained in L-R because You don't really know what is going on
I think ASW can be generated by multible front speakers. You really should try matrix stereo
As You know my hearing is rather poor
I can't hear any sound coming from the floor, I don't miss those small details which are lost according to You and some others, to put it shortly - I am generally happy with FCUFS Linkwitz defends such position ...BUT with the front wall FAAAAR behind the speakers
On the other hand some instist (Floyd Toole among the many) that front wall reflection is nothing but bad. I think that in most typical listening situations they are right.
what You describe here is certainly not a FCUFS' sound
Many early humans were cave dwellers, caves have very reflective ceilings.
Obviously "all studies" do not show that human vertical sound localization ability is generally poor, as mine showed 100% of those tested had excellent vertical sound localization ability
.
throughout the evolution rather ocassional dwellers and a typical listening cave's
"ceiling" is rather dispersive Obviously "all studies" do not show that human vertical sound localization ability is generally poor, as mine showed 100% of those tested had excellent vertical sound localization ability
all academic and peer-reviewed
Thank you for making my point!
Potentially millions of people who own a 5.1 system can and do. I do personally. You no longer have to extract it from a recording, we record ambience directly to a track or several tracks.
Yes you do. The L-R signal is a difference signal that is full of decorrelated out of phase information. It is a signal that is extracted from the LT and RT coming from the front speakers. A decoder takes that information, delays it by a few millisecond and sends it to L/R surround speakers. You can use high speed logic circuits to increase the separation of the front and rear signals, and you can use a decorrolator to split the signal into a psuedo stereo signal.
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Sorry Frank, ain't buying what you are selling here. I think it is pretty widely known that ITD will cause the soundstage to shift to the speaker one is standing closest to. I don't care if the speaker is a flooder, omnidirectional or direct radiator. The only way to change this is to have a phased array speaker. DBX had one called the SF-1. 14 drivers where in the speaker, and the inner ouput of the speaker was stronger than the output closest to the wall. As you walked up to one speaker, you could clearly hear the other speaker. The center image did not shift as you moved around the room.
Sorry, putting my wallet back in the pocket.
Fair enough,
...What has to be understood is the most crucial aspect of achieving this effect is that the quality of replay has be sufficient, there is a very clear boundary of quality that must be reached. If you're 95% of the way there, 99% of the way, 99.5% of the way, to that quality, then what I talk about won't happen; all the things you mention will dominate - you will easily be able to pick out the speaker, the sound will obviously be coming from the speaker nearest you, etc, etc. And everyone will be able to rest comfortably with what the standard research says ...
If all the research has never had the quality of replay to that level, then obviously there will be nothing in the literature. And since that quality is damn hard to achieve, and maintain, this absence of investigation is easy to understand. In one sense this is a true bootstrap situation, one has to work on 'blind faith' that it exists, if it hasn't been personally experienced ...
I undestand. Still m-channel recs are a minority. And what about the ASW?
is this what Elias does?