Soundtrackmixer, you are so right i think.
We don’t hear like a pair of microphones, when recordings sound “real” it is usually more the skill of the mix engineer than a real “captured image”.
This makes evaluation of loudspeaker difficult as one is using the ‘believability” as a major criteria and that is the sum of the flaws in all the parts including the room and using source material that you have never heard first hand.
If one was willing to set stereo aside for a moment and go with one channel, that can be telling I think.
Many people have measurement microphones now days and have sound cards that outperform the tape recordings I grew up with.
I would urge people with both to make some for fun recordings around your house. Just record the noises all around you, These sounds are the ones you are most familiar with AND organic sounds are often harder to reproduce than music (as they are not usually harmonic in nature).
Unless you compress them or clip or are noise limited, they are full dynamic range.
The down side is a measurement mic while flat in response is omni directional which your ears are not so the recording has more “room sound” than what is experienced firsthand..
With one speaker, you can hear another aspect about loudspeakers that is not measured.
Here is how it is manifested. Imagine a black curtain, behind it are two loudspeakers. You play a soft dry voice through each and you can clearly tell where each speaker is and estimate how far behind the curtain each is.
Now, you play a soft voice with short and long reverb and rolled off highs through each. Like before it is easy to tell where each is but one still sounds like it’s right behind the curtain and the other now sounds farther away in an ambiguous location behind somewhere.
I ran into this odd effect working on some speakers for work some years ago. Like the MTF’s being some kind of an indicator of resolution at the listing position, I am sure this what I called spatial identity is part of stereo imaging too. The idea being we hear with two ears and could only localize the loudspeakers physical depth IF what was reaching each ear was enough different (a complex radiation pattern).
Two identical signals (like a single source in the distance or simulated by two identical equidistant sources)“sound like” straight ahead somewhere mono phantom (or floating in your head not having the clues your outer ears normally provide). When auditioned outdoors (no room) , when the loudspeakers depth location is easily localizable by ear, it is more likely to present a mono phantom as a right and left source with an image in the middle. When the speaker is less localizable in depth, it is less likely to be audible as a right and left source which can make the mono phantom image stronger.
Best,
Tom Danley
Danley Sound Labs
We don’t hear like a pair of microphones, when recordings sound “real” it is usually more the skill of the mix engineer than a real “captured image”.
This makes evaluation of loudspeaker difficult as one is using the ‘believability” as a major criteria and that is the sum of the flaws in all the parts including the room and using source material that you have never heard first hand.
If one was willing to set stereo aside for a moment and go with one channel, that can be telling I think.
Many people have measurement microphones now days and have sound cards that outperform the tape recordings I grew up with.
I would urge people with both to make some for fun recordings around your house. Just record the noises all around you, These sounds are the ones you are most familiar with AND organic sounds are often harder to reproduce than music (as they are not usually harmonic in nature).
Unless you compress them or clip or are noise limited, they are full dynamic range.
The down side is a measurement mic while flat in response is omni directional which your ears are not so the recording has more “room sound” than what is experienced firsthand..
With one speaker, you can hear another aspect about loudspeakers that is not measured.
Here is how it is manifested. Imagine a black curtain, behind it are two loudspeakers. You play a soft dry voice through each and you can clearly tell where each speaker is and estimate how far behind the curtain each is.
Now, you play a soft voice with short and long reverb and rolled off highs through each. Like before it is easy to tell where each is but one still sounds like it’s right behind the curtain and the other now sounds farther away in an ambiguous location behind somewhere.
I ran into this odd effect working on some speakers for work some years ago. Like the MTF’s being some kind of an indicator of resolution at the listing position, I am sure this what I called spatial identity is part of stereo imaging too. The idea being we hear with two ears and could only localize the loudspeakers physical depth IF what was reaching each ear was enough different (a complex radiation pattern).
Two identical signals (like a single source in the distance or simulated by two identical equidistant sources)“sound like” straight ahead somewhere mono phantom (or floating in your head not having the clues your outer ears normally provide). When auditioned outdoors (no room) , when the loudspeakers depth location is easily localizable by ear, it is more likely to present a mono phantom as a right and left source with an image in the middle. When the speaker is less localizable in depth, it is less likely to be audible as a right and left source which can make the mono phantom image stronger.
Best,
Tom Danley
Danley Sound Labs
Tom's spatial identity is something that becomes dominant when the system overall is working well, even mono recordings lose all connection with the reproducing speakers and develop a great sense of depth, if the cues were picked up by the microphones.
At an optimum level it becomes impossible to localise the speakers in a directional or depth sense, even if you move up to and deliberately try to "hear" the speakers working ...
Frank
At an optimum level it becomes impossible to localise the speakers in a directional or depth sense, even if you move up to and deliberately try to "hear" the speakers working ...
Frank
fas42,
I think you just described a pulsating sphere.... I have never seen a speaker that did not give some clues as to position if I walked up to it if it was a full range device. Even on omni speaker is going to have a source component to the sound. Perhaps outdoors from a distance you could achieve something like that.
I think you just described a pulsating sphere.... I have never seen a speaker that did not give some clues as to position if I walked up to it if it was a full range device. Even on omni speaker is going to have a source component to the sound. Perhaps outdoors from a distance you could achieve something like that.
This is a behaviour that can only occur if the sound is very, very clean. And possibly it will depend on how an individual's hearing apparatus is wired up inside, I haven't done any "rigorous testing" of such. I know it happens for me, and so I've made it the goal line when I working on improving a system.
As far as I can tell, what's happening is that the direct sound from the drivers, and reflected acoustic information in the room is sufficient to override the remaining acoustic clues that the driver is the source -- the brain is "convinced" that the sound is coming from where the illusion has "projected" it ...
Frank
As far as I can tell, what's happening is that the direct sound from the drivers, and reflected acoustic information in the room is sufficient to override the remaining acoustic clues that the driver is the source -- the brain is "convinced" that the sound is coming from where the illusion has "projected" it ...
Frank
I could walk up to and around the whole speaker without the sound coming from the speaker at all. It was uncanny. Not 360 deg, but a fair amount. First time I heard it was a wooden Iwata horn on an Onken bass bin (don't remember the tweeter). It's one of those strange events you don't forget. The sound just didn't stick to the speaker at all. It always sounded like it was somewhere else. Have heard it since, but it's rare.
That is what I would have to infer from what you are saying, that you could not localize the horn, I would love to see that......
Seriously, and not being hard on you or anything but to have the image not connected to the horn or compression driver and floating somewhere in space not attached to the horn and driver.
Seriously, and not being hard on you or anything but to have the image not connected to the horn or compression driver and floating somewhere in space not attached to the horn and driver.
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Pano,
As FrankWW just suggested please describe the setup and room conditions to achieve this result. I am having a very hard time fathoming how it is possible with the on axis response from any and all horns I have ever encountered. I know the Iwata has an unusual outer contour but that shouldn't invalidate waveguide function and compression driver on axis response with rising frequency. If that be the case why haven't you ditched the Altec's and replaced them with the Iwata horns, sounds like audio heaven to me!
As FrankWW just suggested please describe the setup and room conditions to achieve this result. I am having a very hard time fathoming how it is possible with the on axis response from any and all horns I have ever encountered. I know the Iwata has an unusual outer contour but that shouldn't invalidate waveguide function and compression driver on axis response with rising frequency. If that be the case why haven't you ditched the Altec's and replaced them with the Iwata horns, sounds like audio heaven to me!
It's pleasing to see that Pano has experienced this, always good to encounter parallel occurrences ...
As he stated, it's a rare thing to have happen, because everything has to be "right". So far I've come across only a handful of people who understand what it's like ... as he says, it's spooky!! First time I got it it was a big shock, totally unexpected ... and I've been chasing it ever since ...
Big point: doesn't need horns, or directional sound, and such things. The absolutely essential requirement is super clean sound, because the ear/brain doesn't get fooled easily; efficient horns are an easier way to getting that quality of sound from the drivers, but I've done it with absolutely standard, boring boxes. Trouble is, the slightest problem with the quality of the playback and the "mirage" collapses, the sound drops back into the speakers, and it just becomes another hifi system ...
Frank
As he stated, it's a rare thing to have happen, because everything has to be "right". So far I've come across only a handful of people who understand what it's like ... as he says, it's spooky!! First time I got it it was a big shock, totally unexpected ... and I've been chasing it ever since ...
Big point: doesn't need horns, or directional sound, and such things. The absolutely essential requirement is super clean sound, because the ear/brain doesn't get fooled easily; efficient horns are an easier way to getting that quality of sound from the drivers, but I've done it with absolutely standard, boring boxes. Trouble is, the slightest problem with the quality of the playback and the "mirage" collapses, the sound drops back into the speakers, and it just becomes another hifi system ...
Frank
Because I've heard the Altec multi-cells do it too, when the planets align. Have also heard big coax on open baffle do it.
Yep, that's exactly my experience and pursuit.First time I got it it was a big shock, totally unexpected ... and I've been chasing it ever since ...
Me too, that's why I've been chasing it.
The rooms I've heard it in were mostly of good size, but not huge. Good acoustics and room treatment. I'm sure that helped. I'll try to describe more later, gotta run right now, another early morning gig tomorrow.
Attachments
![A5 [825] horn cab_515B directivity plot.gif](/community/data/attachments/313/313791-8ff180bd6fb1de473ccd53889eff14a7.jpg)
I would have to say to this question, no. Since this is my goal in the first place, I don't think they have to.
This is a definate no. My customers are looking for the best audio presentation they can get for their money.
I am going to say neither. I tailor my microphone set up to the acoustics of the hall. If the hall is acoustically excellent, then I use fewer microphones with a less directional pattern. If the acoustics are not so great, I closer microphone positioning, more of them with a tighter pickup pattern, and try to avoid the acoustics of the hall as much as I can. There is no one formula for any hall, they all require a multi-position points to capture the best out of the orchestra and the room itself. The content itself(the music) also play a huge role. Different microphone techniques will give different results for different music, in different halls. No one size fits all in recording techniques.
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No, this is stereo reproduction, both speakers working. And the track can be a conventional stereo recording, or true mono - it works in both cases. The key seems to be achieving below a certain level of distortion in the playback, at the point where the drivers couple to the air; the drivers don't have to be anything special in of themselves, but most importantly the treble has to be got right. Everything I've got this on, up to before the current unit, was standard 2 way, fabric and the like dome tweeters.
One thing that stands out, is that the room itself is unimportant: 3 different rooms, different shapes, heights; no treatment, no special placement ...
Frank
One thing that stands out, is that the room itself is unimportant: 3 different rooms, different shapes, heights; no treatment, no special placement ...
Frank
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How far do you set them in the hall, and how few microphones do you use?