Just wondering what you think of this first attempt of my recording of a local wood, there's the main subject that I get closer to, then halfway through its just ambience, there is some traffic noise but was excited to try it out to see what the effects would be like, for me, I think it's not a bad first attempt, what do you think? I hope to get back when it's not raining, and maybe an early rise to catch the dawn chorus, but that's pushing my luck I think! It's a parabolic dish type, plugged into a Zoom F3, this is actually binaural, not stereo, so would love to hear your opinions. It's still going through builds and slight modifications.
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First test of my new mic in the local woods (1 Viewer)
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Jon.Bryant
Well-known member
Sorry, but what do you mean by the recording is binaural?
My understanding is that for binaural recordings, you use a dummy human head, with the two mics set in the ears. The idea is then that the dummy head creates the kind of reverberations that happen in our skulls, and help us judge sound direction. Apparently it is not just the time difference and signal strength that we detect, but a sound to our left actually reverberates through our skull, changing frequency, and we detect this also in our right ear…. And vice versa.
I understand that binaural tries to capture the effect that happens in our skulls, and the result is best appreciated using headphones - the captured sound should be played back direct into the ear, to be as near as possible to what the dummy head captures. On this basis, if this is binaural, listeners should use headphones to assess the recording.
What I don’t understand is
1/ How can you place a dummy head in a parabola?
2/ If you can fit a dummy head in a parabola how can the two mics be in focus, when the mics are circa 7 inches apart?
3/ If you have overcome the above, how can a highly directional mic like a parabola, be ‘compatible’ with a binaural recording, which is meant to capture a more 3D sound? I would have thought for a start that the dish would block sounds from behind. For higher frequencies the focus of a parabola is very narrow, so there seems to me a contradiction here - sounds above, to the right or left and out of focus, would then presumably sound more distant, compared to sounds in focus… so a kind of warping of the soundscape. I think this happens with a stereo parabola, but then you are generally wanting to capture the subject, with a quieter ambiance.
4/ Finally, was the mic static or handheld and how do you intend to use it in future? I normally focus a parabola on a target, and often hand hold the mic to track the bird. For this reason I am not that sure about stereo or binaural creates the desired effect. A bit like the target standing still and the world spinning around it, as you move the mic. Whereas this effect does not seem to apparent of displeasing, I think that if you really want to capture a sound and the spatial relationship, the mic needs to be static.
I will try listening with earbuds to see if I can detect any binuaral effect. But if you can explain what you have done and how you think it works, it would be interesting.
My understanding is that for binaural recordings, you use a dummy human head, with the two mics set in the ears. The idea is then that the dummy head creates the kind of reverberations that happen in our skulls, and help us judge sound direction. Apparently it is not just the time difference and signal strength that we detect, but a sound to our left actually reverberates through our skull, changing frequency, and we detect this also in our right ear…. And vice versa.
I understand that binaural tries to capture the effect that happens in our skulls, and the result is best appreciated using headphones - the captured sound should be played back direct into the ear, to be as near as possible to what the dummy head captures. On this basis, if this is binaural, listeners should use headphones to assess the recording.
What I don’t understand is
1/ How can you place a dummy head in a parabola?
2/ If you can fit a dummy head in a parabola how can the two mics be in focus, when the mics are circa 7 inches apart?
3/ If you have overcome the above, how can a highly directional mic like a parabola, be ‘compatible’ with a binaural recording, which is meant to capture a more 3D sound? I would have thought for a start that the dish would block sounds from behind. For higher frequencies the focus of a parabola is very narrow, so there seems to me a contradiction here - sounds above, to the right or left and out of focus, would then presumably sound more distant, compared to sounds in focus… so a kind of warping of the soundscape. I think this happens with a stereo parabola, but then you are generally wanting to capture the subject, with a quieter ambiance.
4/ Finally, was the mic static or handheld and how do you intend to use it in future? I normally focus a parabola on a target, and often hand hold the mic to track the bird. For this reason I am not that sure about stereo or binaural creates the desired effect. A bit like the target standing still and the world spinning around it, as you move the mic. Whereas this effect does not seem to apparent of displeasing, I think that if you really want to capture a sound and the spatial relationship, the mic needs to be static.
I will try listening with earbuds to see if I can detect any binuaral effect. But if you can explain what you have done and how you think it works, it would be interesting.
Jon.Bryant
Well-known member
Now listened to it with earbuds. Strangely I get the impression that everything is now behind me. Could this be because the dummy head was facing outwards and is mainly capturing the reflected sound (hence coming from behind the head). If so it would be interesting to try facing the head inwards to capture the reflected sound as if it was in front of the hearer.
I cannot really detect anything above or below - everything sounds slightly above me, but on one level. Perhaps this is due to the soundscape - Wren, Chiffchaff and ambient noise. It would be interesting to try a recording with something obviously at a different level - say a Song Thrush singing from the top of a tree.
As I say everything sounds strangely behind me, so I suspect the dish does block (or substantially reduce the balance of sound) for 180 degrees.
Finally the Chiffchaff does seem to wonder around from behind central to behind right, even mid song. Could tjis be because of refocusing the parabola.
It will be interesting to see if others hear the same ‘behind you’ effect.
I cannot really detect anything above or below - everything sounds slightly above me, but on one level. Perhaps this is due to the soundscape - Wren, Chiffchaff and ambient noise. It would be interesting to try a recording with something obviously at a different level - say a Song Thrush singing from the top of a tree.
As I say everything sounds strangely behind me, so I suspect the dish does block (or substantially reduce the balance of sound) for 180 degrees.
Finally the Chiffchaff does seem to wonder around from behind central to behind right, even mid song. Could tjis be because of refocusing the parabola.
It will be interesting to see if others hear the same ‘behind you’ effect.
I am still playing with the design is some ways, but, for my own "at home sat down in comfy chair" wearing my good closed backed headphones, this recording, even though I occasionally wafted to dish about a little to pin the source, is a raw recording, and an edited one with the "perfect" cuts in editing would have given you a false sense of what it was I was doing, but, if I try again, I will edit down for "perfect" still shots and try to only capture movement from the birds themselves, if any. The ambience that is going on that is surrounding the subject, and on my little walk, did that sound binaural (externalised) to you?
The little bird, for me at least, seemed to be in front and slightly above at some points, within my bubble of what surrounds me (with my eyes closed).
I have been making binaural microphones since 2013, and the conventional way that most people assume would be correct for binaural recordings, I feel are not quite correct, as possibly demonstrated here? in my opinion, but at the end of the day, you, the listener are the ones to be the judge of that, if listened to correctly, either via headphones, neck speakers, or even correctly placed stereo speakers.. If one were to assume you can't use speakers, and never try them, then the assumption lives on, however, if you position the speakers correctly, then binaural cues can be very immersive, PLUS, you can add your own binaural cues from your own ears, and are able to move your head left/right a little and the originating sound will be where it should be, and not follow your head movement, again, only by trying this would the assumption of it not failing would be realised, please note.. this works in a small movement, not extreme.
If you ignore the technical side of what it is I am doing, and listen to the recording in a very detailed manner, and to scrutinise it, what is your opinion of it? While wearing headphones to start of course?
Your question 1/ How can you place a dummy head in a parabola?
You can't in the traditional sense, but, a head is actually unimportant. This dish is 36cm in diameter.
Your question 2/ If you can fit a dummy head in a parabola, how can the two mics be in focus, when the mics are circa 7 inches apart?
You can't in the traditional sense, but, a head is unimportant, the ears are vital, I'll let you use your imagination in how you think I have done this, for now (more fun that way).
Your question 3/ If you have overcome the above, how can a highly directional mic like a parabola, be ‘compatible’ with a binaural recording, which is meant to capture a more 3D sound?
Compatible? I don't know what you mean, as anything binaural, is exactly that.
Binaural audio are perceptions that are externalised from the head, as with vision, it is externalised. So any recording that appear to be externalised have some form of binaural information infused with the sound, or else, it would be perceived inside the head, and likely to be stereo, or mono.
Your question 4/ Finally, was the mic static or handheld and how do you intend to use it in future? I normally focus a parabola on a target, and often hand hold the mic to track the bird. For this reason, I am not that sure about stereo or binaural creates the desired effect. A bit like the target standing still and the world spinning around it, as you move the mic. Whereas this effect does not seem to apparent of displeasing, I think that if you really want to capture a sound and the spatial relationship, the mic needs to be static.
I was hand holding it, future use probably on a stand. It is very directional, and has not been optimised for correct mic positioning yet.
I am wondering, if like when you use binoculars that perspective is flattened, that the binaural focus of the main subject would also be flattened (or brought simply closer), and the spurious environmental stuff outside the focus spot is more of a true sense "binaural" without the flattening effect, so perhaps this would create a subject standing out very proudly form any background sounds, if any were captured at the time, you could always layer a new sound on top of the main subject I guess, but I have not tried this, and is not something I am looking at, but could be a side effect in this particular use.
I am very excited to play with this idea, and I have only had one other opinion so far, and they seemed to think it was pretty good, so hoping for more than one opinion of this rather from a personal nature friend.
I would love any opinions of the bird call be it positive or negative, I know it's a raw recording and not edited so that it's just the bird, there are other aspects of the recording that I have deliberately left in so that the experience of using the microphone is experienced.
Great! (i posted my reply and then saw your new post)
Binaural in the traditional sense does have the unwanted effect for some, not all, that the sounds can be perceived behind them, simply due to the shape of your ears being quite different to the ones used to make the recording. I did move from one position to another, so went under the chiffchaff 180 to the other side on a higher point in the wood, less than 20 meters or so.
You seem to think everything was slightly above you, though as I point directly at the subject, then the angle of the ears could be positioned differently so that the reflections from the dish hit the ears at a different angle, I will look into that. Thank you for taking the time to listen!
Jon.Bryant
Well-known member
Yes, quite possibly, but I would also be interested to understand if the head is mainly picking up bounced sound, therefore reaching the head from behind.
I have an ambisonic mic (which I admit I don’t use as often as I should). The 4 track ambisonic recording can be ‘rotated’ and then the sound rendered to binaural. But when you do this there are a large variety of heads that you can select for the rendering process. I understand that it is important to get the dimensions as close as possible to the listener to get the best effect - and I am sure this would be the same if using a physical head to make a proper binaural recording.
This is a slight ‘problem’ with binaural - it is not such a good effect for people with non standard heads. I haven’t tried rendering my recordings to different heads yet, but I can see that I could end up having to produce recordings for me, the wife and potentially friends (…although they may think me a bit weird when I ask to measure their heads). For wider distribution, perhaps options with head dims in the metadata!
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Jon.Bryant
Well-known member
I suppose it depends on what your definition of binaural is? In my understanding binaural is meant to capture a 3D sound, so in a perfect setup we perceive things as being all around us - in front, behind, above, below, left and right.
A parabola applies unequal gain to different frequencies - the higher the frequency the more gain, but the narrower the focus (so maybe a 15 degree cone for a high pitched sound). The unequal gain is meant to recreate nearness - if you record something like a Common Nightingale that sings over a broad frequency range the ‘balance’ will be different from the frequency balance had you used a non parabolic mic. As high pitched sound decays quicker than low pitched sound, this distortion of the frequency balance is as if you had stepped forward and were much nearer to the bird. The Sound Aproach suggested parabolic recordings were more bird’s ear, rather than human ear sounds - it can be as if you were sat on the branch in front of the singing bird.
The focus then becomes front and centre and the ambient a little incidental. The Common Nightingale in focus sounds very close, but the Blackbird out of focus has a ‘true’ frequency balance (assuming the mic has a flat frequency reponse), and is also markedly quieter quieter. The mic creates a large distortion of the 3D world, and a directional recording - by this I mean a recording where things in focus predominate.
I personally have tried to use binaural for sound scapes. But then I want the Reed Warblers to sound like they are the reed bed in front, the bittern more distant on the left, the blackbird singing from the scrub behind, and the Swallows flying around and over my head. I wouldn’t want a Reed Warbler to sound like it was right in front of me and to dominate, or the sound behind me to be blocked.
With a parabola if you can capture a 3D sound, then the swallow example above becomes a bit weird. The in focus bird sounds like it is very close, but when it flies out of focus it sounds like it has suddenly taken on a burst of speed and zoomed further away.
All that said, I can see that a bird’s ear recording of a bird in focus, with a 3D(ish) capture of the incidental and ambient sounds in front of the dish would sound pleasing. I presume this would work best with a static target, do that the world does not spin, by altering the mic direction.
I will wait with baited breath for you to explain your method.
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Thank you for clearing that up! Here's an insight to where I am coming from, as I can clearly see where you are in regard to the technical abilities and equipment you use for your interesting hobby, and passion.
It's a bit long, sorry.
Ok, 3D sound, that's one way of saying "binaural", so What is "binaural" Binaural audio, when listened to correctly would be sounds perceived as if they were external from the head, if you have good hearing, it is the way that you are perceiving sounds yourself, right now.
Many people confuse binaural as with stereo, which is quite disappointing to say the least, not that I suggest that you are implying that, it's just the nature of reality that this confusion exists.
Instead of "3D" we use "binaural" everyone should realise that it is sound which is externalised, there are thousands of "binaural" labelled video on YouTube that are merely stereo, and ignorance is gathering momentum by the fact that people who see that, simply assume that binaural is stereo. So frustrating really.
Then, a sore subject for many, if it (binaural) does not seem to meet the confines of the technical speak of many years of written papers where much research has taken place, so anyone new there, are immediately bombarded of the dogma that surrounds it, as long as everyone agrees with what everyone else says, them all is good. and woe betide anyone who tries to suggest anything else, ouch!
So then, if we drop all the technical aspects of what it is, and how it supposed to be capture etc etc etc... What does it sound like?
If by chance it is externalised, then by nature itself means it's binaural in some form, as it is externalised, there is no other way to externalise sounds other than infusing some kind of new information that mono or stereo do not have by their very nature. When I was a child my father purchased some stereo headphones, they had a volume control on each cup, and when I experienced that for the first time I was confused as the sounds were inside my head! For my entire existence of my 11 years on the planet, I had experienced sound externally continuously, until then. It took many decades and an accidental viewing of the virtual barber shop on YouTube that got me thinking about externalised sounds again. Fortunately, I did NOT look for what it was on the Internet, but I simply experimented with various mics and combinations of really stupid ideas that were driving my curiosity to find the reasons. for MONTHS I was experimenting, looking for the perfect contraption that would give this externalisation. I'm not one for giving up, so after I had run out of ideas, I resorted to the boring hard work of thinking, and thought and thought I did, mostly when I couldn't sleep at like 3am in the morning. Anyway, I realised that it was all down to the ears, and to prove this hypothesis at the time I asked a friend to help me cast my ears, and from there everything fell into place, I found the answer and successfully managed to realise how to capture binaural audio (3d sound I called it at the time) all by myself, a huge ego boost it was. From that I found many nuances of binaural audio, and still find little bits that add to the incredible subject of it as I still find the time to think about it, still with me? Bated breath, breathing hard enough?
So my incredible journey of binaural audio is ongoing, to this point in the area of audio, parabolic dishes. It's very fresh to me, so finding new angles of it is happening most of the time. Naturally, ears inverse most of the sounds to the ears canal, as reflections off the pinna, so adding a dish, another reflection is taking place, the ears are looking to the inside of the dish, and it was suggested that the ears should be upside down, but turning the dish upside down didn't really have that much effect, and i think it is the angle of the pinna to the dish that is important at the moment. I do think that the perspective is changed as you pointed out, I still think it is flattening it like visual flattening when using binoculars, but I am only guessing there.
Every microphone, so it seems, has a particular purpose, so a combination of a standard binaural microphone with a standard dish combo would be interesting, though, you could layer the sounds so that the recording of the subject wasn't duplicated on both the dish and binaural mic, I'm sure that would sound odd. So I wonder if this could do away with a combination, and bring it down to one mic (depending on the purpose), as the binaural cues that are not focused are subdued, and externalised, from the one and only recording I have made in the woods yesterday, I hope to go back there today, with a standard binaural microphone (not head) and the dish, just to compare the externalisation. I 3D printed the ears from my own ear and mirrored them so they were symmetrical (for aesthetics), it was by reading the forum that I put a baffle between each side of the dish, so this is a very new area of my binaural antics, and I am really enjoying it, even though the white paper technical aspects of binaural audio I am not following and don't actually agree with it, as I think at the beginning someone overlooked an aspect of it that has by default been excluded due to the physics of those technically brilliant - as my old boss said to me being too clever can get you into trouble, so maybe if there is something that has been overlooked, no one is looking for it, but myself, I think I have found the bit they overlooked, so anyway, the placement of the ear on the dish are completely in contradiction of the conventional means of recording binaural audio, and, if people think it does sound externalised and, more to the point, sound good to them, then what I am doing is pushing new ideas about it. What if I'm wrong~?? It won't affect anyone, or anything, people will still get binaural audio confused with stereo and vice versa and the tech guys can happily amuse themselves in agreement.. But what if I'm a cat? And about to ponce on the pigeons? haha
I wonder if you care to ponder, rather than timing differences, what if it is colouration of tones that a pinna induce onto the sound that is the fundamental aspect of binaural audio? As I have found a head is not important, and the distance between the ears appears not to be that important either, as long as it's not too extreme of course. The only way to realise it, is to make copies of your own pinna, and to experiment with them, so that many aspects of what you would find, could question the very core of the beliefs you had created with the technical aspects that are well known. If your brain is shouting at me here, I would accept that, and perhaps have another read, or if you are with me, and looking at it from a fresh angle, where do you think you could take this idea? Would you have any suggestions that I could try? Nature recording isn't my thing at present, so I'm quite green, most of my recordings are of people and the outdoors with binaural microphones. I am located in Lancashire, so if there is somewhere local to me, perhaps you could make some suggestions for me to get some more examples, and to put the prototype through some hoops.
Jon.Bryant
Well-known member
Sorry misread this. Is it shape or position of the ears? I thought it was more do do with position - how high up and far back the ears are on the skull. I also thought size of skull is important.
As I say, one techie paper I read suggested that the 3D effect is partially how our brain interprets sound that resonate through the skull to the other each, and not just sounds reaching the ear direct.
The pinna shape, they all have the same features, aka to a face, but all slightly different, so colouration maps are slightly different for all. So the pinna is vital to your map, else there is confusion, mostly front becomes back, as in your experiences.
I have removed the head and experimented with shorter distances between the ears, my latest incarnation proved the function, as the guy I recorded shouted out to me while listening back to the recording! (a question I asked on the recording) , so I decided to try the dish, it's just as an idea, nothing more, I think it works quite well considering it's in a dish, my assumption of its function was quite wrong, in a nice way.
I have removed the head and experimented with shorter distances between the ears, my latest incarnation proved the function, as the guy I recorded shouted out to me while listening back to the recording! (a question I asked on the recording) , so I decided to try the dish, it's just as an idea, nothing more, I think it works quite well considering it's in a dish, my assumption of its function was quite wrong, in a nice way.
3dpan
Well-known member
My first impression, listening on Sennheiser HD560S, is very good. Good spatial effect, direction and distance, from the peripheral birds (mostly in the right field).
The main subject does sound distorted. You are using the F3 presumably in 32bit float, so I wonder if maybe your mic capsules are overloaded ?
Which capsules are you using.
I would like to see a pic or two of your parabolic etc arrangement.
I have built my own DiY SASS mic for widefield stereo of dawn and twilight chorus.
I also use a commercial "stereo" parabolic mic (540mm dia) for concentrating on a single bird call, supplemented with a lower level stereo ambient field.
I also use the ZOOM F3 recorder.
NB, I use the term "stereo" out of ignorance, maybe I should think binaural ?
The main subject does sound distorted. You are using the F3 presumably in 32bit float, so I wonder if maybe your mic capsules are overloaded ?
Which capsules are you using.
I would like to see a pic or two of your parabolic etc arrangement.
I have built my own DiY SASS mic for widefield stereo of dawn and twilight chorus.
I also use a commercial "stereo" parabolic mic (540mm dia) for concentrating on a single bird call, supplemented with a lower level stereo ambient field.
I also use the ZOOM F3 recorder.
NB, I use the term "stereo" out of ignorance, maybe I should think binaural ?
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Hi, thank you for your opinion!
I did notice that the capsules did get it tough when I was closest to the bird, the capsules in this test was AOM5024, normal mics I would use would be EM272-Z1. I'll try them sometime.
Stereo is use of two mics, or two channels, binaural is anything with ears, or, maybe even stereo mics that have reflections that cause similar tones of what the pinna do (inside enclosures etc) in my opinion.
Hope the pics go down well :O)
Attachments
3dpan
Well-known member
My parabolic mic has two pairs of AOM5024. My first SASS had two pair of EM272, my second SASS has two pair of AOM5024 (they're cheaper than EM272, and a bit more sensitive ?)
I haven't noticed a problem with the 5024 or 272 overloading, but maybe I'm not close enough to the subject.
So stereo mics with a baffle eg Jecklin disk would be binaural ?
It's well after midnight here, so I'll look closer at your pics tomorrow.
Cheers,
A.
Nope, because they do not have ears.
I think I was a little too close for the capsules crapping out a little, I find the EM272 superb for bird call, as they don't crap out, but only tried the AOM as I was also testing a new circuit with them.
I'm uploading a little video describing in a little more detail of the function of the dish, which is speculative, after talking to a friend about it, I realised he was a sound board and I explained it to myself, so that's going up shortly. My understanding of that was that there is a bird of prey that has binocular vision in the centre, and standard vision outside the centre, which could describe what is going on here, as the ears are not "hidden" by the dish until almost 180 degs to the side, so standard binaural cues are to the extreme left and right, and attenuated from the rear, and "zoomed in" at the focal point.
I wonder if it helps with how it's working for some?
Binaural dish test - youtube
Jon.Bryant
Well-known member
This is not quite how I understand binaural to be.
If I make a stereo recording, and play it out of speakers that are correctly positioned, then the sound appears external to me. In fact the sound 'is' external to me - it is produced by speaker cones that are some distance in front of me, and to my right and left. There are multiple stereo techniques and these can create various 'image width', but this can sound wrong - if you want it to sound as if the pianist is directly in front of you, you don't want it to sound as is the keyboard is 4m long!
Stereo has been a great success for music, where the sound is on a single plane, and we only have to have to recreate the sense of in front, left and right. The performers are virtually never above, below or behind us.
But what if you want to capture a wider sound? This is where I understand binaural, ambisonics and surround sound come in.
To me binaural has to be something more than just 'external from the head'. I has to give me the impression of three dimensions - that the sound is all around me, or at least that the sound is in front of me, but sounds to my left, right, up and down. This is why I say it would be interesting to hear a recording with birds clearly singing at different levels. I am not trying to criticise your set up, but to me at the moment I am not sure whether it is binaural or merely stereo (but with my odd ears, the impression the speakers are behind me!)
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Hi thanks for your detailed reply.
Binaural isnt very well understood, there are so many miscommunications about it, people labelling stereo as binaural is just one of them.
Stereo speakers, if you play stereo through them, you will not get anything that is above, or below, as you are hearing the sound from the speakers without binaural information.
If on the other hand you play binaural audio through them, correctly positioned, if you made a binaural recording of a bird in a tree above you, then, when played back through the speakers, you wouldn't hear the bird coming from the speakers, but from above the speakers, because the binaural information is included on the sound.
I understand the confusion you are going through trying to comprehend what it is I am saying IF you are using conventional ideas of what it is, as this is indeed in conflict to the comprehension.
If you place your headphones on your shoulders and listen to binaural aircraft coming in to land at a local airport, Cessna etc, then the low flying aircraft will be perceived above your head, and NOT coming from the headphone speakers on your neck.
Once you have the "penny dropped" moment, you will realise that it is the binaural cues of the sound that create the perspective as to where the sound is coming from. It took me months to realise what the "binaural" part of the audio was, and when it came I sat bolt upright in bed and said out loud "its my bloody ears", and having made casts of them, I have actually proven the hypothesis that it is indeed the pinna that are the "lenses" of the auditory world, just as eyes are lenses of the visual world, strange that both of them are externalised, an i don't mean speakers, I mean the perception of the sound is externalised, only really noticed with headphones unless listening to aircraft or birds in trees. I wouldn't expect anyone to "get it" without some examples and thinking to look at it from a different perspective than the one you were expecting, a bit like changing the colour of a fruit drink to orange and tasting strawberry, it will tell you something different as your eyes will try to deceive you, just as a preconceived idea to trick you into not looking at it from a correct perspective. I hope that makes sense to you.
Have a listen to some binaural examples with your headphones on your shoulders for a start, as anything you perceive from above will get your brain thinking "what is that!" because it will defy your comprehension, when you do not know what binaural information truly is. I am positive that any binaural bird recording that are above the mic in the trees, or at a distance to the left or right will have a big impact on what it is for you, only by listening differently will you discover the magic of binaural audio, as I did, through creative ways of listening and not of the conventional manner. I really hope that you can find some time to experiment with other ways to listen, as if we all stick to "only wear headphones" then you will never find out that there are other ways to experience it.
One last thing, if a head was really really really important for binaural, then why don't cameras have heads? As to be as closely in line with nature, the eyes are in a head, and there are two of them, yet, photography works without the head, and just a little box, just as binaural doesn't need a head, just two pinnas, as they are the lenses for the audio, just as camera lenses are for the film. I wish I could put it even more simply, but due to preconceived ideas this makes it a huge challenge, you have top move your perspective to a new way of looking at it, else you won't get it.
Did you see the little video i uploaded to YouTube in my message above? From that, you may find some connection, or maybe it will just confuse you some more?
Jon.Bryant
Well-known member
I have listened to and been very impressed by binaural recordings, so I am not sure what you mean by the 'penny dropping' - I do think that binaural recordings are possible, and that it is not some new-age rubbish made up by some 80's music producers. I personally have only had good 3D effect using headphone (despite my odd ears, and interesting I have never had the sensation the sound was behind me before). I suspect that a neck collar would also work, but have not tried one.
Where I think we differ in opinion, is that you consider that the binaural effect is ear shape, whereas from what I have read it is more to do with how sound resonates through our heads that helps creates our 3D world. It may sound implausible, but we only have to think how sound travels through brick walls, window glass etc. This resonance generally also includes a frequency change, depending on material density, and it is suspected that our brains can process this information. Our right and left ear drums are not therefore in a completely isolated sound chamber, only exposed to sound comming down the ear canal. This is why some recordists have tried to create very realistic heads with the same density and void structure as their own, in an attempt to capture the sound as if at the eardrum, including sound passing through the ear, and sound resonating through the skull. The apparent importance of head structure, also explains why software engineers such as the designers of the Reaper ambisonic to binaural rendering plugin, have focused on rendering for a confusing array of head dimensions (I think there may be over 100), rather than just simply different ear shapes. I can imagine that ear shape could impart binaural cues, but can you not also imagine that head structure may also be important to create the fuller set of cues and hence more spatial sound?
As I say, I personally cannot detect an up or down in your recording, so from what I have listen to, I am not clear it you have actually captured sufficient binaural cues, by using ear shape alone. It admit though that something is going on, because it sound behind me. If you give me a recording that has clear variation in height, I will humbly admit that the above - and a fair chuck of binaural literature - is incorrect and that ears shape is all important.
I am really not sure about your statement about listening through speakers. As the mics are capturing the sound, as if the mics were placed in our ears, then from what I have read, the sound needs to be played back as close as possible to the same position in our own heads - As I say, I have only experienced good 3D effect through headphone. The binaural recording technique captures the sound inside a head (or in your case ear), so it needs to be played as if it is inside our head. If we were to listen to binaural recording produced through correctly positioned speakers, then we are in effect passing the sound through our outer ear structure twice (the sound is also resonating through our head twice) - once in the dummy head and once in our own heads!. Perhaps we would still get some binaural effect, but this double pass may also muddy the binaural queues - the recording is as if it is above, but our own ears are telling us it is in front. For sure, your recording does not sound behind me, if I play it through my computer speakers (which may not be perfect, but I have reasonably well positioned).
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I agree with your statement about listening to binaural through speakers, and you ALMOST got it!!! You do indeed place your own binaural cues on to the sound, so that you can turn your head for a sound to the right and while turning left, it would appear to stay at the right because of your own pinna cues! I am very pleased that you tried thinking about this difficult subject in much detail.
Anyway, all this technical speak is taking us away from the original thread, which was "how does it sound"
We can get technical later if that is something that you, or others, want on another thread perhaps?
I think this idea has great advantages, and some disadvantages, but like all microphones, each has a particular purpose, if this fits in with a new purpose, I think that would be awesome. I have more recordings done today, but I don't think they were as good as my first attempt, as it was busy with people families and dogs. I took a binaural mic and the new dish mic to compare, I'll have to try another day when it's not busy.
Jon.Bryant
Well-known member
Having looked at your video and pictures, it appears to me that
1/ The ears are not close to the focal point of the dish, so will not be gain from the dish. You can look up focal point of a parabola and measure your dish to calculate where this is, but on my various dishes it is 'within' the bowl of the dish - I can easily place a wind cover over the front of my dishes without it coming into contact with the mic. Your 'ear mics' appear to me to be to far our from the parabola cup.
2/ The ears are facing in, so appear positioned to capture the reflected sound. If you look at the maths for a parabola then only sound directly in front of the dish is reflected to the focal point where the mic is positioned. Sound from outside focus may hit the dish, but will not be reflected onto the focal point where the mics are. We could imagine this in reverse by considering a high powered torch, and the narrow beam - light reflected from the bulb is cast forward only. To try and further demonstrate what I mean, Telinga produce a Twin Science mic capsule - this mic includes a omni mic and a cardiodal mic, and by changing the position either one of these mics can be brought into focus and optimised. The omni is less directional, but the inward facing cardiodal is incredibly directional, as it rejects all sound coming from directly behind the mic and only picks up sound in focus reflected by the dish - ambient sound is effectively cut out. Stereo parabolas work by using omni mics - the target is captured from the reflected sound hitting the mic, which is concentrated and hence louder, but the stereo ambience is captured by the sound reaching the mics direct without reflection. This same mechanism creates a problem with your set up - do you face the ears out to capture ambience or inwards to capture the reflected sound in focus.
Given the above two points, I suspect that this is why I hear the sound as if behind me - the ears are predominantly picking up direct and not reflected sound as the mics are not positioned at the focus of the parabola.
1/ The ears are not close to the focal point of the dish, so will not be gain from the dish. You can look up focal point of a parabola and measure your dish to calculate where this is, but on my various dishes it is 'within' the bowl of the dish - I can easily place a wind cover over the front of my dishes without it coming into contact with the mic. Your 'ear mics' appear to me to be to far our from the parabola cup.
2/ The ears are facing in, so appear positioned to capture the reflected sound. If you look at the maths for a parabola then only sound directly in front of the dish is reflected to the focal point where the mic is positioned. Sound from outside focus may hit the dish, but will not be reflected onto the focal point where the mics are. We could imagine this in reverse by considering a high powered torch, and the narrow beam - light reflected from the bulb is cast forward only. To try and further demonstrate what I mean, Telinga produce a Twin Science mic capsule - this mic includes a omni mic and a cardiodal mic, and by changing the position either one of these mics can be brought into focus and optimised. The omni is less directional, but the inward facing cardiodal is incredibly directional, as it rejects all sound coming from directly behind the mic and only picks up sound in focus reflected by the dish - ambient sound is effectively cut out. Stereo parabolas work by using omni mics - the target is captured from the reflected sound hitting the mic, which is concentrated and hence louder, but the stereo ambience is captured by the sound reaching the mics direct without reflection. This same mechanism creates a problem with your set up - do you face the ears out to capture ambience or inwards to capture the reflected sound in focus.
Given the above two points, I suspect that this is why I hear the sound as if behind me - the ears are predominantly picking up direct and not reflected sound as the mics are not positioned at the focus of the parabola.
The setup is a "happy Accident" I have merely positioned the mics at a point where I can fix them to the dish, however, they have amplified the sounds, it may yet not be tweaked for prime focus. The dish is also squinted, as the front mic holding bars are pulled towards each other, slightly deforming the dish, which I believe may be another happy accident.
The ears face inwards, as they are pointing to where the sound is coming from, if pointing outward, the pinna flaps would attenuate the signal.
For me, the sound is at the front, as they are my own ears. I understand that there are lots of technical aspects of a dish, but i will not try to blind myself with that at present as it can hinder progress in some ways, especially if it's not fully understood. I must say that I do not always believe what I read, especially If I have figured out something for myself.
I have much to say about binaural audio, but most do not want to hear it, as it isn't with what the scientific community believe so will fall on "deaf ears" pun intended..
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