The magic of stereo
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Steve williams
Site Founder, Site Owner, Administrator
Tom, this is another thread here that also fascinates me and I wonder if this is similar to your work
http://www.whatsbestforum.com/showt...onics-What-it-is&p=34403&viewfull=1#post34403
http://www.whatsbestforum.com/showt...onics-What-it-is&p=34403&viewfull=1#post34403
Magic Stereo! Facsimile...
Live music is not Stereo, it is Multidimensional.
Can you record that multidimensionality? That is the question Frank! (Not you Frank, another one.)
...And then reproduce it, in Phase, in your own Different room, and with Two Loudspeakers?
That is the other question Frank! Or should I say the Quest!
I think that those two processes are completely different and cannot be connected with the same dots, in the different spaces, from the grooves, or the zeros & ones, with the same auditory verity!
For sure you can be totally satisfy in the Live situation, and in the reproductive process of your own home, but does it make it the Real thing? That's not another question Frank, it just doesn't!
But the satisfaction remains because we know and we feel and our brains reconstruct the missing dots, in tandem with what's coming from our Stereo loudspeakers, and enters our ears.
And that, is the simple 'Magic'!
At night, when the sky is dark outside, and the stars are dancing in their nocturnal hall,
and that all the children are sleeping, and that I'm sleeping as well;
I can hear Music playing in the background.
My dreams are becoming Musical. But it is not in Stereo then. It is in Magic!
Yesterday, I went to bed early. But just before that I was listening to some Classical Opera music from the r.a.d.i.o. And I was at peace, relaxing and comfortably numb.
It was not in Stereo then, it was in Angelical and Grandiose space of a Hall!
Today, I woke up early. But just before I woke up I was in a dream.
Sometimes I remember my dreams very well, and this morning I did again!
It was about my best friend...
Bob
Live music is not Stereo, it is Multidimensional.
Can you record that multidimensionality? That is the question Frank! (Not you Frank, another one.)
...And then reproduce it, in Phase, in your own Different room, and with Two Loudspeakers?
That is the other question Frank! Or should I say the Quest!
I think that those two processes are completely different and cannot be connected with the same dots, in the different spaces, from the grooves, or the zeros & ones, with the same auditory verity!
For sure you can be totally satisfy in the Live situation, and in the reproductive process of your own home, but does it make it the Real thing? That's not another question Frank, it just doesn't!
But the satisfaction remains because we know and we feel and our brains reconstruct the missing dots, in tandem with what's coming from our Stereo loudspeakers, and enters our ears.
And that, is the simple 'Magic'!
At night, when the sky is dark outside, and the stars are dancing in their nocturnal hall,
and that all the children are sleeping, and that I'm sleeping as well;
I can hear Music playing in the background.
My dreams are becoming Musical. But it is not in Stereo then. It is in Magic!
Yesterday, I went to bed early. But just before that I was listening to some Classical Opera music from the r.a.d.i.o. And I was at peace, relaxing and comfortably numb.
It was not in Stereo then, it was in Angelical and Grandiose space of a Hall!
Today, I woke up early. But just before I woke up I was in a dream.
Sometimes I remember my dreams very well, and this morning I did again!
It was about my best friend...
Bob
Last edited:
Amazing, using Etymotics ER4Ps plugged into my laptop. Some of this seems to be due to a binaural recording (intended or not). But the apparently uncompressed dynamics also contribute to the sense of a real space.
You have me intrigued, Bob, who is this pretender!
But also confused, is it me you talk to or not?
Very poetic, your post, must have been a good wine ...
Frank
Bob,
Great post.
Recreating as much as possible of this multidimensionality is the main purpose of the audiophile activity.
As you refer, due to our human nature, the magic can happen is unexpected ways and conditions. Audiophiles can only increase the probability of getting it!
You have me intrigued, Bob, who is this pretender!
But also confused, is it me you talk to or not?
Very poetic, your post, must have been a good wine ...
Frank
No Frank, I wasn't addressing you at all. It was simply me using a second imaginative person in my post, and I do have a brother named Frank.
But after I finished my post and made some minor corrections, I saw your name above, and that's why I added "not you Frank, but the other one", as to not confuse anyone and certainly not you. I never saw your name before I posted and it is only by pure coincidence that I picked that name for the purpose of my post. I tought about changing it for another name, but instead I just decided to add a small note, to not confuse anyone.
Sorry for the little confusion as the coincidence was some kind of magic and I didn't want to fully destroy it.
The name Frank has a very deep meaning to me; not only because its the name of the brother that I luv deeply, but also because it is a popular friendly name on many films. "My good pal Frank"! "So Frank, when are we going to rob that bank?" ...And so on...
* By the way, I tried to access the link from Tom (Danley), and just couldn't!
And I very seldom drink. I do luv wine, but I stop drinking a long time ago. My mind is in perfect control! Sorry again for the small inconvenience. Also this site is brand new to me and I'm not used to you guys yet. You seem to be all very well calibrated in many things Audio related, and also on the professional level. There are few people here that I am quite familar with, like Kal, and Roger, and I'm sure there are more because I've into this hobby for over 40 years, like other members here.
And I was also a subscriber to most Audio magazines since the seventies. So I read a lot of articles and reviews from several people in this business, plus much much more...
Anyway sorry for the small off track here, it was certainly not my intention.
I just expressed an opinion at the moment from few posts that I read in this thread. And from that I'll see where we can go on the goal of what's best. Because after all, Live music is the very best.
And in our own rooms, in our Stereo systems, what we are doing is listening to some drivers in our speakers, and to an audio signal that was transfer through some electronic components, and before that it was recorded on a recorder machine from some microphones.
It is still amazing what we can get though; the emotions are real strong and that's what makes us pursuing it even further. It's worth it! It is Magic because to listen to what has been taped before is a total new experience, in the sense that we can concentrate in a total different way than the live event.
It is one thing to be there, and another to be transported!...
Bob
You and I are on the exact same page.
...I will add to this that the emotional, or more precisely the spiritual preparation, and the choice of our quality recordings have as much to do than the mechanical tools we are also using, in the purpose of self inflicted auditory and emotional satisfaction. But you already know that. Simply put; for the magic to be happening, it is an ensemble of pure simplicity and complicity.
Might is well finish my post on a good sounding note, no?
Bob
All very nicely put ...
I can only wholeheartedly agree with you, Frank's tend to be a very pleasant amd amiable breed of people, though perhaps not everyone here would totally agree ...
Frank
I can only wholeheartedly agree with you, Frank's tend to be a very pleasant amd amiable breed of people, though perhaps not everyone here would totally agree ...
Frank
I want to add this.
For me, Stereo is easier to digest and comprehend and get used to.
Beside, many speakers have wide dispersion, and they mimic the dispersion of a Concert Hall.
And a Hall has walls, a ceiling and a floor; same as our rooms.
Multichannel SACD versus Stereo; I prefer the magic of Stereo!
For ne it is more powerful, emotional, and better contolled...
Five speakers is much harder to control by the recording engineer, tougher to control in your own room, as there is no speakers on the side or behind you in a Hall, and the phantom image created by your two front mains is also a better controlled sound propagation than a recreated center speaker in another space and time. This is where the gain from simplicity comes into play.
We have much more experience with two, like an happy couple in their mutual complicity, than the complexity of several more interludes.
Indeed, the magic of Stereo is not so magic after all; it is well balanced and well executed and well proportionated in a calculated equilibrium of simplicity and dual complicity.
I'm just in it for the same reason as anyone else!
Bob
For me, Stereo is easier to digest and comprehend and get used to.
Beside, many speakers have wide dispersion, and they mimic the dispersion of a Concert Hall.
And a Hall has walls, a ceiling and a floor; same as our rooms.
Multichannel SACD versus Stereo; I prefer the magic of Stereo!
For ne it is more powerful, emotional, and better contolled...
Five speakers is much harder to control by the recording engineer, tougher to control in your own room, as there is no speakers on the side or behind you in a Hall, and the phantom image created by your two front mains is also a better controlled sound propagation than a recreated center speaker in another space and time. This is where the gain from simplicity comes into play.
We have much more experience with two, like an happy couple in their mutual complicity, than the complexity of several more interludes.
Indeed, the magic of Stereo is not so magic after all; it is well balanced and well executed and well proportionated in a calculated equilibrium of simplicity and dual complicity.
I'm just in it for the same reason as anyone else!
Bob
All very nicely put ...
I can only wholeheartedly agree with you, Frank's tend to be a very pleasant amd amiable breed of people, though perhaps not everyone here would totally agree ...
Frank
Alright Frank, everythting seems to be under control now!
See, Frank & Bob = Stereo! ...Now is that Magic or not?!
Bob
Tom, you're gonna hate me for saying this, but I don't have a problem with stereo OR mono. Most of the recordings I use for fine tuning my gear at the moment are old fellows, almost none of it is stereo. The imaging, soundstage, etc has to be there for me irrespective of whether it is stereo or mono, I couldn't care less about the stereo imaging being correct, it will automatically be so, if the mono sound is up to the mark ...
Frank
Tom, I've posted before that I share your view about 2 channel reproduction. Like many members in our forum, I've heard several SOTA representations of 2 channel reproduction and, no matter how good it is, and no matter how good the recording, I always feel like I'm looking through a window where the music is playing instead of sitting/standing in the room where the music is playing.
I wonder how much number 1 on your list in this thread (your thread) is part of the explanation:
http://www.whatsbestforum.com/showthread.php?2562-Engage-Yourself-Mentally-First
I wonder how much number 1 on your list in this thread (your thread) is part of the explanation:
http://www.whatsbestforum.com/showthread.php?2562-Engage-Yourself-Mentally-First
Now you've got me curious, Ron, when my system is working well I actually get the "looking through a window" effect, which to me is desirable, when the system is not working well then the music is in the room, so to speak. So this is back to front to what feels right to you ...
Would you care to elaborate on your version of "looking through a window"?
Thanks,
Frank
Bob Carver's Sonic Hologram Generator does that for most well-recorded music (well not the 360° wrap around because that's not how an orchestra is laid out, but I do remember watching the movie What Lies Beneath one evening and hearing crickets directly behind me , about 20' back in the room, during a night scene and being non-plused over the possibility of a cricket in my room.. it was the movie soundtrack! Without the Hologram, it came from the speakers. That was before I had surround speakers.. just the array in front.
To this day, when I play some of my Japanese recordings, like The Weathering Continent, some audiophile listeners ask me if I'm playing a 36-channel recording through 36 speakers.
The thing I've found most destructive to the illusion of stereo and 'space' is human vision. I brought a complete stranger into my studio one time, blindfolded and had him listen to a piece of music. He thought that the room was the size of an auditorium and when I yanked off the blindfold, he was staring in disbelief at the fact that he was in fact in a much smaller space. When we see the room beforehand, our brain has to undo that reality to allow the mind to experience the space in the recording. Our eyes are constantly telling us it's a livingroom/den/basement, but the recording and our ears are telling us it's Symphony Hall. ?
I definitely agree about the distractions of vision. No doubt the reason a lot of us choose to turn down the lights and close our eyes Mark
My thoughts on those who don't like stereo and complain about how hard their brain has to work in order to believe in the illusion that should lie before them is that their stereo system/room interface really isn't very good. On most recordings, I feel like I could reach out and touch the musicians that are playing. I certainly don't feel like my brain is working overtime trying to solve differential equations in order to appreciate the illusion that I'm seeing and hearing. It's just there and it's highly enjoyable.
Tom-I know I got under your skin about this before and it's not my intent even though I admit that when I said I wouldn't recommend a Hafler DH-110 to someone I didn't like I crossed a line I shouldn't have because I upset you and hurt your feelings. I do apologize for that. Sometimes I need to be more diplomatic and politically correct in the words I choose to use. Or I need to preface my remarks by saying “forgive me” and/or put a smiley face at the end of a sentence in order to make everything OK.
I too once owned a Hafler DH-220 that I built from a kit and installed the Frank Van Alstine power supply mod which got rid of what Frank referred to as the "soup can" filter caps. The DH-220 was part of my system for years and it was bullet-proof. And then one day...I traded a Dynavector cartridge that I hated to a guy who was the original owner of a Dynaco ST-70 amp. I brought the amp home. I ordered a new set of Siemens EL-34 tubes and I cleaned the amp up. I installed the new tubes, biased the tubes, and sat down to listen. The funny thing here is that the Dynaco ST-70 and the Hafler DH-220 are both products of David Hafler. The DH-220 was just the modern whizz-bang mosfet amp with much higher power and better bass response than its 35 watt older tube cousin.
If anyone here can tell me that there is any comparison what so ever between the sound of the ST-70 and the DH-220 as far as realism in the vital midrange goes, please go visit your audiologist immediately and see if your hearing can be helped or if it’s too late. The older cousin trounces the DH-220. I sold my DH-220 and never looked back. My point to all of this is that if you are still using low-budget SS stereo equipment from the early to mid 1980s that was never designed or intended to be SOTA in its day, you might want to think about that when you complain about your lack of an illusion when listening to stereo instead of pining for a format that you wish would rise Lazarus-like from the dead.
The funny thing is, the ST-70 isn’t even a really good tube amp even though a gazillion were sold and a gazillion more are for sale right now. But, it was good enough in the midrange to show up the DH-220 as the pretender it was and is. My next amp after the ST-70 was the ARC D-76 and it was everything the little ST-70 could never be. You live and learn. Check out the prices the Hafler DH-220 amps bring on the used market and the prices that Dynaco ST-70s are fetching. You can buy DH-220 amps for around $200 and a working ST-70 is going to cost you about $500. There is a reason for that.
In summary, the better your gear, the more realism it brings to the table. The more realism you have the easier it is to hear the illusion that 2 channel can and does bring to the table. Conversely, the worse the gear is, the worse the illusion is and your brain has to work much harder. The moral to the story is be nice to your brain and buy better gear.
Tom-I know I got under your skin about this before and it's not my intent even though I admit that when I said I wouldn't recommend a Hafler DH-110 to someone I didn't like I crossed a line I shouldn't have because I upset you and hurt your feelings. I do apologize for that. Sometimes I need to be more diplomatic and politically correct in the words I choose to use. Or I need to preface my remarks by saying “forgive me” and/or put a smiley face at the end of a sentence in order to make everything OK.
I too once owned a Hafler DH-220 that I built from a kit and installed the Frank Van Alstine power supply mod which got rid of what Frank referred to as the "soup can" filter caps. The DH-220 was part of my system for years and it was bullet-proof. And then one day...I traded a Dynavector cartridge that I hated to a guy who was the original owner of a Dynaco ST-70 amp. I brought the amp home. I ordered a new set of Siemens EL-34 tubes and I cleaned the amp up. I installed the new tubes, biased the tubes, and sat down to listen. The funny thing here is that the Dynaco ST-70 and the Hafler DH-220 are both products of David Hafler. The DH-220 was just the modern whizz-bang mosfet amp with much higher power and better bass response than its 35 watt older tube cousin.
If anyone here can tell me that there is any comparison what so ever between the sound of the ST-70 and the DH-220 as far as realism in the vital midrange goes, please go visit your audiologist immediately and see if your hearing can be helped or if it’s too late. The older cousin trounces the DH-220. I sold my DH-220 and never looked back. My point to all of this is that if you are still using low-budget SS stereo equipment from the early to mid 1980s that was never designed or intended to be SOTA in its day, you might want to think about that when you complain about your lack of an illusion when listening to stereo instead of pining for a format that you wish would rise Lazarus-like from the dead.
The funny thing is, the ST-70 isn’t even a really good tube amp even though a gazillion were sold and a gazillion more are for sale right now. But, it was good enough in the midrange to show up the DH-220 as the pretender it was and is. My next amp after the ST-70 was the ARC D-76 and it was everything the little ST-70 could never be. You live and learn. Check out the prices the Hafler DH-220 amps bring on the used market and the prices that Dynaco ST-70s are fetching. You can buy DH-220 amps for around $200 and a working ST-70 is going to cost you about $500. There is a reason for that.
In summary, the better your gear, the more realism it brings to the table. The more realism you have the easier it is to hear the illusion that 2 channel can and does bring to the table. Conversely, the worse the gear is, the worse the illusion is and your brain has to work much harder. The moral to the story is be nice to your brain and buy better gear.
garylkoh
WBF Technical Expert (Speakers & Audio Equipment)
Your wish is my command. Track 22 on this disc -
http://www.amazon.com/Stereo-Review-Chesky-Records-Surround/dp/B000003GHE
Hi Guys
Tomelex, you have a good ear for details, you are correct, to the right side about three houses down IS a right angle bend in the road. It was me that walked out to the road, I was trying to be quiet haha. It was a very quiet day, only a few little noises like somebody hammering on a different street etc.
Steve, I can ‘t tell you guys exactly how it was done but I can tell you and Fas42 the process.
Well, I am not sure where to start.
I have been interested in sound most of my life, I am an inventor, not a formally trained engineer.
About 30 years ago, I was lucky to have worked for a company and boss that purchased one of the first TEF machines, a TEF 10.
It (at the time) was amazing in that one could measure things in acoustics rapidly that could not be measured at all or at least very slowly. While my job was developing acoustic levitation transducers for space based container less manufacturing, loudspeakers were my interest.
Over the following years I got to use the newer TEF machines etc at Intersonics, we became known for “goofy / exotic acoustic measurements”. One experience was pretty weird / fun / interesting for me, if you like Egypt;
http://www.livesoundint.com/archives/2000/julyaug/pyramid/pyramid.php
A continuously troubling aspect was in tying what one saw in a measurement to what one hears as a sonic property.
Anyway, my point is that after doing a million measurements on all kinds of stuff, you start to assemble your own view of “how things must work”.
Sound is one of the few things that is near black art, I mean the principals are known but what one has in a given real situation is often very hard to discern being in 3d , invisible and frequency variable.
Coherent addition;
Take a subwoofer at a given drive level. Measure the amplitude AND polar distribution. It have a response and having no directivity (being small compared to the wavelength) has a spherical radiation pattern (or half when on the ground).
Take a second identical subwoofer, same drive level, place it very close to the first and now one has coherent addition and also still has spherical radiation. The level is raised 6 dB however not the 3dB one would expect by simply doubling the power. The difference is when the sources are acoustically small and less than about ¼ wavelength apart, they “feel” each others radiation resistance, the y sum into a single larger more efficient source.
If one were to reverse one of the two, in a perfect world, they totally cancel out, the principal behind active sound cancelation.
Interference pattern;
Take the two subwoofers, in phase again, place them farther apart at say 1 / 2 wavelength at frequency X. Now one finds an interference pattern, cancelation nulls are crated in line with the sources and a doughnut radiation pattern is formed. At spacing’s larger than about 1/3 wavelength, one produces an interference pattern of lobes and nulls. The larger the acoustic spacing between sources, the larger the number of lobes and nulls in the interference pattern. Also, now if you were to reverse one source, you simple re-arrange the radiation balloon.
Consider what is required IF one were designing a speaker one of who’s goals is to provide the same frequency response and phase over a large listening area? I don’t mean the two hot seats at the couch but in a movie theater, music venue or Church? It is EXACTLY the things like the interference between drivers that causes the lobes and nulls, things that cause one seat to measure much differently than another even when the room is excluded, it is a homogeneity in the pattern one is trying for, ultimately, to produce a portion of a simple expanding sphere over the whole band.
Consider what is required if you were designing a speaker to be used in a large reverberant room?
The primary object here is to confine the radiation pattern, to produce the highest “front to back” ratio so that the sound goes where the people are and as little as possible anywhere else.
A strong part of what governs a speakers polar or spherical radiation patterns is the interference between drivers that produces lobes and nulls instead of a simple pattern.
Consider what is required if you were designing a speaker who’s spectral response should not change with distance only the loudness, it must be constant directivity.
Anyway, in order to make speakers that did this, I needed to eliminate the interference between drivers.
In the 12 years or so I have been working on these single source speakers, starting with the Unity horns and current Synergy horn, there has been a progression towards an actual single acoustic source to where now an SH-50 can reproduce a square wave over a decade wide, spanning the crossovers which have no apparent phase shift. As these got better and better, they had several sonic properties which were not obvious in any measurements. If I listened to just one speaker I heard two things, the sound got “simpler”, less busy somehow (this I assumed was because the time smear was getting smaller and smaller) and the weird one, it got harder to hear how far away it was with your eyes closed.
I mean standing say 10 feet away with your eyes closed, listening to a voice, one can easily hear the exact direction, BUT it became very hard to hear how far away the speaker was. A speaker like the SH-50 for example, one can remove the grill and walk up to it and even with your head in the horn mouth, the source is floating somewhere in front of you.
I concluded that one can hear things” about a radiation pattern such that one can obviously hear the source, all the way to real no clue how far away it is. If the radiation pattern is a simple balloon, there is much less information about “where it is” and so what you hear is more of the unfettered source. While our products are rarely used to create a stereo image in commercial applications, the best part for me was that in a living room, the huge forward directivity and lack of source signature produces a totally real phantom mono image or an image anywhere between the two speakers and the enormous headroom made them effortless at any level I would choose.
If you have ever recorded or done live sound, you know her is no way around multiple mics and yet, the more you use, the less real it sounds. A problem similar to the one with multiple sources exists, if you have more than one microphone, you have encoded an interference pattern. You brain interprets these as spatial information however, the clues are mixed up relative to how you would hear them and so even two mic recordings are a pale image compared to live. In the case of the recording thingy, by not corrupting that information, you brain is free to interpret the incoming as depth and such or in the case of tomelex, could hear (correctly) a bend in the road several hundred feet away. That stuff was simply preserved without an interference pattern so your brain could recognize the patterns more firmly.
Where the loudspeakers can supply a continuous image in a full circle with 5-6 channels, I wanted a way to capture that sonic image live. Ultimately (a dream from the way old days) I want to capture and reproduce the upper half of our hearing sphere. One has to collect directional information but not encode the interference pattern multiple microphones collect.
Lastly, to be clear, I have put down what I see as of now, science is provisional, subject to change given a better explanation so things may be different tomorrow. On the other hand, we don’t even sell to the home market so I figure I can say what I think . I am glad there is some interest, I love this stuff.
If you’re interested there are a couple other recordings that might be fun, probably wait until your SAF if so equipped is out of the house before the train and be careful of the fireworks this can tax the most stud like stereo.
Bottom of the page here;
http://www.danleysoundlabs.com/technical downloads.html
Best
Tom Danley
Danley Sound Labs
Tomelex, you have a good ear for details, you are correct, to the right side about three houses down IS a right angle bend in the road. It was me that walked out to the road, I was trying to be quiet haha. It was a very quiet day, only a few little noises like somebody hammering on a different street etc.
Steve, I can ‘t tell you guys exactly how it was done but I can tell you and Fas42 the process.
Well, I am not sure where to start.
I have been interested in sound most of my life, I am an inventor, not a formally trained engineer.
About 30 years ago, I was lucky to have worked for a company and boss that purchased one of the first TEF machines, a TEF 10.
It (at the time) was amazing in that one could measure things in acoustics rapidly that could not be measured at all or at least very slowly. While my job was developing acoustic levitation transducers for space based container less manufacturing, loudspeakers were my interest.
Over the following years I got to use the newer TEF machines etc at Intersonics, we became known for “goofy / exotic acoustic measurements”. One experience was pretty weird / fun / interesting for me, if you like Egypt;
http://www.livesoundint.com/archives/2000/julyaug/pyramid/pyramid.php
A continuously troubling aspect was in tying what one saw in a measurement to what one hears as a sonic property.
Anyway, my point is that after doing a million measurements on all kinds of stuff, you start to assemble your own view of “how things must work”.
Sound is one of the few things that is near black art, I mean the principals are known but what one has in a given real situation is often very hard to discern being in 3d , invisible and frequency variable.
Coherent addition;
Take a subwoofer at a given drive level. Measure the amplitude AND polar distribution. It have a response and having no directivity (being small compared to the wavelength) has a spherical radiation pattern (or half when on the ground).
Take a second identical subwoofer, same drive level, place it very close to the first and now one has coherent addition and also still has spherical radiation. The level is raised 6 dB however not the 3dB one would expect by simply doubling the power. The difference is when the sources are acoustically small and less than about ¼ wavelength apart, they “feel” each others radiation resistance, the y sum into a single larger more efficient source.
If one were to reverse one of the two, in a perfect world, they totally cancel out, the principal behind active sound cancelation.
Interference pattern;
Take the two subwoofers, in phase again, place them farther apart at say 1 / 2 wavelength at frequency X. Now one finds an interference pattern, cancelation nulls are crated in line with the sources and a doughnut radiation pattern is formed. At spacing’s larger than about 1/3 wavelength, one produces an interference pattern of lobes and nulls. The larger the acoustic spacing between sources, the larger the number of lobes and nulls in the interference pattern. Also, now if you were to reverse one source, you simple re-arrange the radiation balloon.
Consider what is required IF one were designing a speaker one of who’s goals is to provide the same frequency response and phase over a large listening area? I don’t mean the two hot seats at the couch but in a movie theater, music venue or Church? It is EXACTLY the things like the interference between drivers that causes the lobes and nulls, things that cause one seat to measure much differently than another even when the room is excluded, it is a homogeneity in the pattern one is trying for, ultimately, to produce a portion of a simple expanding sphere over the whole band.
Consider what is required if you were designing a speaker to be used in a large reverberant room?
The primary object here is to confine the radiation pattern, to produce the highest “front to back” ratio so that the sound goes where the people are and as little as possible anywhere else.
A strong part of what governs a speakers polar or spherical radiation patterns is the interference between drivers that produces lobes and nulls instead of a simple pattern.
Consider what is required if you were designing a speaker who’s spectral response should not change with distance only the loudness, it must be constant directivity.
Anyway, in order to make speakers that did this, I needed to eliminate the interference between drivers.
In the 12 years or so I have been working on these single source speakers, starting with the Unity horns and current Synergy horn, there has been a progression towards an actual single acoustic source to where now an SH-50 can reproduce a square wave over a decade wide, spanning the crossovers which have no apparent phase shift. As these got better and better, they had several sonic properties which were not obvious in any measurements. If I listened to just one speaker I heard two things, the sound got “simpler”, less busy somehow (this I assumed was because the time smear was getting smaller and smaller) and the weird one, it got harder to hear how far away it was with your eyes closed.
I mean standing say 10 feet away with your eyes closed, listening to a voice, one can easily hear the exact direction, BUT it became very hard to hear how far away the speaker was. A speaker like the SH-50 for example, one can remove the grill and walk up to it and even with your head in the horn mouth, the source is floating somewhere in front of you.
I concluded that one can hear things” about a radiation pattern such that one can obviously hear the source, all the way to real no clue how far away it is. If the radiation pattern is a simple balloon, there is much less information about “where it is” and so what you hear is more of the unfettered source. While our products are rarely used to create a stereo image in commercial applications, the best part for me was that in a living room, the huge forward directivity and lack of source signature produces a totally real phantom mono image or an image anywhere between the two speakers and the enormous headroom made them effortless at any level I would choose.
If you have ever recorded or done live sound, you know her is no way around multiple mics and yet, the more you use, the less real it sounds. A problem similar to the one with multiple sources exists, if you have more than one microphone, you have encoded an interference pattern. You brain interprets these as spatial information however, the clues are mixed up relative to how you would hear them and so even two mic recordings are a pale image compared to live. In the case of the recording thingy, by not corrupting that information, you brain is free to interpret the incoming as depth and such or in the case of tomelex, could hear (correctly) a bend in the road several hundred feet away. That stuff was simply preserved without an interference pattern so your brain could recognize the patterns more firmly.
Where the loudspeakers can supply a continuous image in a full circle with 5-6 channels, I wanted a way to capture that sonic image live. Ultimately (a dream from the way old days) I want to capture and reproduce the upper half of our hearing sphere. One has to collect directional information but not encode the interference pattern multiple microphones collect.
Lastly, to be clear, I have put down what I see as of now, science is provisional, subject to change given a better explanation so things may be different tomorrow. On the other hand, we don’t even sell to the home market so I figure I can say what I think . I am glad there is some interest, I love this stuff.
If you’re interested there are a couple other recordings that might be fun, probably wait until your SAF if so equipped is out of the house before the train and be careful of the fireworks this can tax the most stud like stereo.
Bottom of the page here;
http://www.danleysoundlabs.com/technical downloads.html
Best
Tom Danley
Danley Sound Labs
Stereo & Holographic Magic!
Some recordings out there are simply & truly magic!
I don't know about the Phase interaction or not but the Holography is "epoustouflant"!
One of those recordings is this one (Stereo CD) on 'fathom' records:
Bob
Some recordings out there are simply & truly magic!
I don't know about the Phase interaction or not but the Holography is "epoustouflant"!
One of those recordings is this one (Stereo CD) on 'fathom' records:
Bob
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