Here's a classic "OMG I can hear him moving around" recording that works with the cheapest of headphones: https://www.youtube.com/watch?v=IUDTlvagjJA Most of the audio experience quality comes out of the production phase, and artists can put as much or little effort into that as possible and consider several mediums of listening (headphones, TV, surround, concert, vinyl) and make tradeoffs for the medium's particular experience.
I don't know about double blind trials but people do tests on their own. It's further complicated though because the hardware you use could be optimized for certain types of music, e.g. have a read through http://arstechnica.com/gadgets/2014/07/some-of-the-worlds-mo...
Did you think about your experiment? What's your own conclusion, and what other conclusions would you expect others to make? "Just think about it" is not a very convincing argument.
The microphones would probably be the bottleneck in reproducing the sound. If your microphone setup doesn't perfectly model the ears of the listener (with respect to how the headphones are worn and their frequency response), you're not going to be able to plausibly reproduce the whole sound field using a stereo recording. That has little to do with sample rate, though.
A long time ago, recordings were made by putting a microphone or three in a place near where the audience was sitting at a performance.
If you get it right -- don't flip the phase of the signals, use appropriate microphones, and get good levels all the way through, record to a really good medium -- you can get amazing results.
If you are certain that the music will be played back through headphones, you can embed two mikes in a mock-up of a human head -- better yet, inside the ears, and require playback through in-ear monitors -- and get an amazing sense of realism.
That's not the way most music is produced these days, though. That's like a single-author software project with everything written from scratch: there are some, but not many.
Music is rarely made in real-time at a live performance. It's usually made in an editing suite after dozens, hundreds or even thousands of individual recordings, samples and synthesized effects are made, gathered or licensed. These elements are brought together, altered, fused, and made into a final bitstream that represents the producer's best effort at realizing their musical intent.
You can get amazing things out of that process, too. Works that could not reasonably be made any other way.
However, in that workflow, the original real world spaces in which the source materials were made -- if any -- are mixed and lost. To produce stereo in a two-channel final recording, many tracks are simply assigned to one channel or both channels at specified volumes. This loses or confuses phase and delay information that humans use for spatial location.
The crossfeed filters are another post-processing step, this time in the hands of the audience playing it back, that can simulate some of that spatial location information. It can do this to a greater or lesser degree; the more information available at the beginning of the process (about spatial location), the more can be introduced.
Eventually we might see artists routinely producing multiple final products, some of which have been rendered to virtual spaces for headphones or IEMs, others being set for surround configurations or stereo playback. Better software tools will help with that -- a scriptable 3D GUI that places your virtual instruments and virtual audience in a virtual ambience could be immensely useful.
I am by no means a professional audio engineer, but I p?l?a?y? ?o?n?e? ?o?n? ?T?V? am a lifelong audio enthusiast, so these are my clearly my opinion, but:
I once did an experiment recording a solo piano concert in a beautiful music hall. One instrument only, not a band or a group. I created two setups for the recording, one was with two traditionally-placed high-end mics, and the other was with a binaural head recording unit sitting in the audience.
Afterward, I asked several people to compare the two recordings and give me their opinion.
Many comments about the traditional mic setup were quite favorable ("this recording is very clean" or "very pristine" or "this sounds like a good CD recording", etc.). But without exception, every person who then listened to the binaural recording gasped or exclaimed about how realistic it sounded. About how it sounded like they were sitting there in front of the piano. Some even had goosebumps.
The very-good-but-standard stereo setup recorded reverb, overtones, harmonics and so much more in a beautiful way, but the binaural recording caught the subtle cues and millisecond differences in right ear-left ear perception that can fool the brain into thinking it's live. It's not just about 'stereo separation' or 'left-right panning'.
Check these out (ONLY WITH HEADPHONES) for an idea of why binaural audio is so interesting (even better if you close your eyes and do not move your head while listening):
https://open.spotify.com/track/6CXy9faZUH6K49dcJOikK9?si=b8b...https://open.spotify.com/track/2U46YhTirldVjofuErenz7?si=579...
Headphones with a proper HRTF preserve that perfectly fine better than any actual speaker setup ever can. The typical demo for this functionality is https://www.youtube.com/watch?v=IUDTlvagjJA
>So let's just be crude engineers here. Every listener has 2 ears. Using headphones and 2 tracks (stereo) you can control precisely what sound is heard by each ear. You can replicate anything a human can hear, which includes direction in all 3 dimensions of space. This is very similar to 3D using glasses to make separate images each viewed only by one of your eyes. You could even go further with VR head tracking to alter the channels based on your head movement to turn your head to look at the sound source and have it move to be in front of you - maybe some VR people are doing that too but I doubt that is what is being branded "Atmos." Is it?
Notice how none of what you describe is standard stereo, except as a base layer, and 99.99% of music available in stereo doesn't magically offer that?
What stereo encoding of music in two channels can support on top of it, and the base stereo two-channel mixing and playing is not the same thing.
The whole spatial experience is added on top of that. All those extra "you can just" and "you can just" that you describe need extra logic on the DAW and mixing side to control the stereo field and translate positions chosen in a spatial mixer down into relative volumes and time differences in the streo field, so that you get the spatial placement. And of course you need extra logic and sensor and real-time processing to do the head tracking.
All of those are not just "stereo" the same way the web is not "just tcp", and Dropbox does not amount to the same thing as just "An FTP account, mounted locally with curlftpfs, and then SVN or CVS".
And then somebody had to re-mix those tracks from Eno, using the original multi-tracks (not just the master), make decisions about spatial placement for each element, and use Dolby Atmos software in some DAW or specialized mixing too to encode this down to stereo information.
(And that's just for the headphone case, Dolby Atmos extends to multi-speaker setups and cinema audio).
>There are some techniques to make a "dry" recording "wet," by basically faking the room tone, but they're, well, fake. Tossing in a little reverb and messing with the EQ is never going to give you the same effect as the natural acoustics of a concert space.
I disagree with this. It's certainly true of most "reverb" plugins, but it's possible to measure the frequency response curves of famous concert halls and exactly recreate the effect of sitting there, down to the details of how your head shapes the sound coming from different directions. It just comes down to how accurately you can measure the impulse response function. The physics implies that this is basically perfect, modulo the quality of our recording gear.
To do this, you set up microphones as your "ears" where you want it to sound like the person is sitting, and then go on stage and do one of two things. Either fire a blank from a gun, or play a tone sweep. (The latter is more common these days.) From the recording of the way the sounds bounce around the room, you can generalize all of the linear behavior of the reverberation (which is all you are interested in anyways.)
From this you get a convolution kernel, then just convolve that with your dry signal.
You can actually get something that sounds identical to a binaural recording out of this.
I don't know: the stuff I remember hearing was pretty amazing and there wasn't an ear measurement step in the listening process. If what you say is correct I wonder how perfect the match has to be in practice. (but, to the point regarding the magic headphones: this is something that could happen in the software if you're simulating the whole thing)
Based on experience, I would say that the most critical part of that chain is the recording technique and quality, followed closely by the audio reproduction.
To get the most amazing, lifelike experience you are seeking, however, (and in my opinion) you would most likely need to be using high quality headphones and a similarly high quality recording made using the binaural mic technique. This technique mimics how sound waves travel around your head and into your ears.
A good binaural recording will shine only when you listen with headphones, don't even bother trying with speakers. If you've never heard it before, it will probably shock you.
I thought this was going to be about adding spatial audio processing [1] to recorded music. One of the reasons recorded music is uncanny is that the act of listening to something with stereo channels piped directly into your ears is vastly different than listening to the same music in a room as it is affected by the room's dynamics.
There is a lot of work being done in VR research labs to simulate realistic audio by using the correct transfer function when playing the audio track. If done properly, listening to prerecorded audio of a concert would be indistinguishable from a live concert. But doing it correctly requires dynamically adapting the audio stream for the user's head & ear shape and ear position with respect to the audio source.
Synthetic spatial audio that passes a Turing test has been done in the lab but we probably won't see it in consumer devices for a few more years. VR headsets and Airpods are slowly getting there, but they don't simulate the user's ears.
Maybe my recordings are shitty mate, but in general they're REALLY good. There is another one called Holophony, which is a patented technique of recording binaural audio, (by some guy named Hugo) which is multitudes better than plain binaural recordings! I want you to check out if you feel the same way for these PROFESSIONALLY recorded holophonic recordings too:
I don't know about double blind trials but people do tests on their own. It's further complicated though because the hardware you use could be optimized for certain types of music, e.g. have a read through http://arstechnica.com/gadgets/2014/07/some-of-the-worlds-mo...
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