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High Resolution Audio: Does It Matter?

j_j

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Which ones?
I am only familiar with Mercury and the Decca tree using 3. Most of the others used variations on the spaced omnis and crossed cardioids in my recollection which may be suspect, I am old.

There are many other methods. The "multimiking" I refer to is using many mikes inside the orchestra and then mixing them down to stereo. Somebody thought it was a good idea at DG and made a bunch of thin-sounding 2-channel recordings, thanks to the zillions of comb filters thus created.
OTOH
I don’t like all the extra speakers and cables needed for multi channel either, any minuscule spatial special effects one may get from applying some sort of algorithm to make multiple channels out of two is faux and not worth owning extra equipment for.

I do have a centre and rear channels for the rare occasion I watch a film so have tried this faux surround but went back to stereo in the end.

First, the center channel playback in a proper system must match L and R.
Second, Center is the primary channel for good 3-channel spatial audio.
Third, no you can't make it up out of 2 channels, you ***must*** have three properly produced channels to start with, and no, movies don't count.
Fourth, no, center is not "just for voice". That's a thing that's necessary for cinema, but not for home listening.

upmix systems are not multichannel, they come under the heading of "special effects" to me, and I'm also quite unimpressed.
 

Blumlein 88

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So bottom line, while overkill and wasteful of space, recording at 88.2 khz or 96 khz takes these possible filter effects out of the picture, right? Or out of the window of audibility?
 

j_j

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So bottom line, while overkill and wasteful of space, recording at 88.2 khz or 96 khz takes these possible filter effects out of the picture, right? Or out of the window of audibility?

With a sensible filter (and some ADC's don't!!!) yes. That's also true at 64kHz, of course. I can't come up with anything beyond 64kHz being as cautious as possible.
 

Blumlein 88

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With a sensible filter (and some ADC's don't!!!) yes. That's also true at 64kHz, of course. I can't come up with anything beyond 64kHz being as cautious as possible.
Read your ideas on this many years ago, and they make sense. When recording or playing back for most gear 64 khz isn't one of the choices. So 88 or 96 are the next best.
 

j_j

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Read your ideas on this many years ago, and they make sense. When recording or playing back for most gear 64 khz isn't one of the choices. So 88 or 96 are the next best.
Oh believe me, I know. 32 and 64, for narrowband and wideband, make all the sense. So we don't do that.
 
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krabapple

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Which ones?
I am only familiar with Mercury and the Decca tree using 3. Most of the others used variations on the spaced omnis and crossed cardioids in my recollection which may be suspect, I am old.

Deutsche Grammaphon was/is famous for it. Karajan was a fan. If you don't know about that, look it up. It means mic'ing subsections, or even individual instruments, of the orchestra separately. Far more than just 3 microphones. Then mixing all those tracks down to two.
 

krabapple

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upmix systems are not multichannel, they come under the heading of "special effects" to me, and I'm also quite unimpressed.

They are not multichannel recordings, obviously, but upmixers render multichannel output from them. And as you doubtless know, it's not the same as silly 'all channel stereo' or 'party mode' (all channel mono) effects....the algorithms actually do attempt to 'extract' and steer content to different channels. The results are hugely source dependent (as well as upmixer dependent) and range from simply 'embiggening' or creating greater sense of envelopment (steering 'reverb' to the rear channels -- this is what happens to 99.9% of 'classical' stereo tracks run through Dolby PLII) to surprising circular-surround-like 'panning' effects (try any 60/70s rock recording where heavy phasing was used). There are recordings where I prefer the 2 channel stereo upmixed to 5.1, to an existing dedicated 5.1 mix .

It goes without saying that matched and balanced and properly delayed speakers improve the experience...that's true of 'real' multichannel as well.
 

j_j

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Deutsche Grammaphon was/is famous for it. Karajan was a fan. If you don't know about that, look it up. It means mic'ing subsections, or even individual instruments, of the orchestra separately. Far more than just 3 microphones. Then mixing all those tracks down to two.

Yep, harsh, thin recordings. Consider, if you have n microphones in the same soundfield, you get n*(n-1)/2 comb filters, all in parallel. That is, unless you do something more than just add them all together in synchrony.
 

Blumlein 88

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Yep, harsh, thin recordings. Consider, if you have n microphones in the same soundfield, you get n*(n-1)/2 comb filters, all in parallel. That is, unless you do something more than just add them all together in synchrony.
Way back one of the DG LP horrors I purchased had a chart in the sleeve which showed the layout of the orchestra and where the microphones were. I think there were 42 microphones. It sounded dreadful. Like you say all the combinations of comb filtering. The music sounded shredded.
 

tuga

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Way back one of the DG LP horrors I purchased had a chart in the sleeve which showed the layout of the orchestra and where the microphones were. I think there were 42 microphones. It sounded dreadful. Like you say all the combinations of comb filtering. The music sounded shredded.

And if the recording sounds too "dry", use reverb or do it in a church. :facepalm:
 

Frank Dernie

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Deutsche Grammaphon was/is famous for it. Karajan was a fan. If you don't know about that, look it up. It means mic'ing subsections, or even individual instruments, of the orchestra separately. Far more than just 3 microphones. Then mixing all those tracks down to two.
Of course, multi track recordings but that came much later and, of course loses all hall ambience (so fine for studio recordings) and any phase integrity in the mix (if that matters). It does give a potentially lower noise floor though because there is so much less ambient noise.

You can certainly manipulate the sound with microphone positioning and this multi track means much more manipulation is possible - post recording too, which is useful if the recording has faults.
When I first started making my amateur recordings in the mid 1960s microphone position was the main means of balancing the recording.

Personally I still prefer the sound of a pair of microphones over the conductor's head to a multi track mix down. Quite a few years ago somebody involved in a new recording of Handel's Messiah linked some clips of two versions on one of the hifi forums, one from the simple mike pair and one a multi-track mix down. I preferred the ambience of the simple recording but they decided to release the multi-track version. It is still a nice recording but I was disappointed not to be able to buy the simple recording since the ambience and spatiality seemed much more natural to me. I appreciate the clarity of the mix down and can see why some may prefer it.
I am not one of them.
 

Frank Dernie

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First, the center channel playback in a proper system must match L and R.
Second, Center is the primary channel for good 3-channel spatial audio.
Third, no you can't make it up out of 2 channels, you ***must*** have three properly produced channels to start with, and no, movies don't count.
Fourth, no, center is not "just for voice". That's a thing that's necessary for cinema, but not for home listening.
These are amongst the reasons I am sticking to stereo. Even if there are a limited number of recordings with 3 or more channels done properly I don't have any. I have a lot of music and performances I like collected over the last 58 years. At home I would rather listen to music I like on a simple system than music I like less, chosen purely for sound quality, on the best system available. HiFi shows proved this to me decades ago :)
 

Rednaxela

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Personally I still prefer the sound of a pair of microphones over the conductor's head to a multi track mix down.
Do you by chance know if this is an example of such a recording?

From the booklet:

85BF822E-2FF5-45FA-B545-BF7A91879F9F.jpeg
15679547-67D9-468C-951A-A8F3120B40C2.jpeg



(Sorry for the off-topic question.)
 

Blumlein 88

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And if the recording sounds too "dry", use reverb or do it in a church. :facepalm:
I think the recording I'm thinking of was done in a church. It was just dreadful. I've heard some recordings with quite a few microphones sound pretty good. DG didn't know how to do it in the 1980s or whenever that was.

I've done a few recordings in churches. As much as I like a good two or three microphone recording you have a higher chance of a good result with a stereo pair of cardioids up front, and a couple omnis further back in the building. Mix the omnis in until you get the amount of room sound you want. Go a little close with the pair up front.

Then when I've been lucky a pair of spaced omni's up front can be pretty special. I was once recording a practice session having some good results with a pair of spaced omnis up front, and a pair of hypercards out in the middle of the building pointed toward the ceiling. A technique I read about from some Japanese recording people. Seemed to get a more decorrelated ambiance that wasn't heavy and over-powering the way some omnis in that spot can be.
 

Blumlein 88

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Do you by chance know if this is an example of such a recording?

From the booklet:

View attachment 216149View attachment 216150


(Sorry for the off-topic question.)
Well there are at least 4 microphones in the picture. Two over each shoulder of the conductor and one for each choir.

Usually the classic techniques were not like this picture. Maybe if they were omnis.
 
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D

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More or less. the Fc is actually the transition band of the filter and the width is fc*2, not fc/2 in frequency, and the width in time is inversely proportional to fc, i.e. the faster the cutoff, the longer the time response. The key to making sure that there is no possibility at all of a problem is pretty simple, move it up a few kHz, and it's all over, so to speak. You can't get detection when it bounced off the eardrum. The mathematical model here is somewhat of a match to something resembling an actual cochlear filter, but this is actually a touch better (in terms of smear), and a few orders of magnitude easier to actually calculate.

The bump at the end also exists at the beginning, but isn't shown here because of when I started and stopped the analysis. It's way, way down.

Later I will show what a filter with a wider transition band is like. But now I'm outside digging up an overgrown patch of horseradish.

My bad. By Fc I meant the sampling rate. A slip due to my formal education years notation I'm used to, in another language.
I think we're saying the same thing, if we swap Fc with Fs.
 
D

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...
You will also note that the "spread part" in the middle is wider, and much more similar to the "overall" response.
...

View attachment 216104

I'm not sure what you're referring to here. I see a shorter time "smear" around the cut off frequency, indicated in black.
I also see a more wide band initial detection time, extending all the way down to the bass frequencies, around 10 time units, indicated in green.
However, the bass region looks a lot more rugged after the first detection than in the sharp cut off filter example. It does have an initial rise around 10 time units that's similar to the rise around Fs/2, but then rises and drops a couple times (highlighted in red).
So could we possibly be talking about a trade-off?
I also used the correct english naming convention on the frequency scale.

1656852113758.png
 

anmpr1

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And if the recording sounds too "dry", use reverb or do it in a church. :facepalm:
I've heard some recordings with quite a few microphones sound pretty good. DG didn't know how to do it in the 1980s or whenever that was.
It wasn't just a DGG thing. Bad recordings, I mean. Someone had to make the decisions, and we must remember how in the 'early' days of stereo a lot of people wanted a stereo demonstration to show off their hi-fi. If they bought Igor and David Oistrach, they wanted to hear Igor and David, even if their violins were louder than the Wiener Symphony that was behind them. Something to show for their extra dollar, which was what a stereo record cost.

Few people really thought of 'natural' sound, at least in the context of living room imaging and accurate placement of instruments in their records. Why? Because a lot of music lovers placed loudspeakers wherever they were unobtrusive--their idea was simply to fill the room with sound. Think back. If you don't remember people with hi-fi systems in the '60s (maybe you were too young), then look at photos of subscriber systems from old Audio magazines. Audio typically featured reader's systems. Typically, loudspeakers were not set up with pinpoint imaging in mind, but rather hidden/placed in locations no one would think about doing, today.

In important ways, early and mid classical recordings were not that different than pop recordings. Consider the EMI Ring--the first released stereo recording of that work. It was a major event, but really was an event in artificiality. Multiple short takes, with the best of the bunch subsequently spliced together to form each extended act. Rheingold anvils? Reports tell how real anvils (that were difficult to record because transients would overload the tape head) were used, because of a desire for 'authenticity'. How authentic were they in the final mix? Sadly, the contrast between anvils and orchestra is not a happy one. While orchestral parts and singing highlight the venue's acoustical properties (echo/reverb), the anvils were placed in the center of the mix, scrunched up, monophonic, and really out of place, not keeping with the sonics of the rest of the recording. They could have used a little 'artificial' reverb within the context of this highly artificial recording.

My recollection, FWIW, was how audiophiles were less concerned over how it was recorded, than the poor quality of the physical product you bought in stores. In the US you paid about a dollar more for DGG imports, in addition to a dollar more for stereo over mono, but the quality of their vinyl was no better than what you'd get from domestic RCA or CBS. That concern, and not how many microphones were used, was the biggest concern to consumers.

Finally, I have to wonder how much the recording industry was influenced by manufacturers of pro gear. Did microphone and console 'reps' push their gear to record execs in questionable ways? Was it simply the appeal of 'flash and bling'? From a human nature standpoint, who wouldn't want to work in a fancy million dollar studio, with all the latest multichannel gear at your finger tips?

In any case, once 'audiophile' oriented classical recordings (featuring better miking techniques and quality vinyl) made the scene, consumers had a choice: 1) top tier artists, but poor quality recordings that you might not want to listen to for very long; or 2) high quality recordings, but average artists that you might not want to listen to for very long.
 
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