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Inside High-res audio: PCM vs MQA vs CD: 2L Sampler Comparison

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#22
So, we can 'see' high frequencies problems with most HiRes files. But can we 'see' (or 'spot') a difference between a 16 bits and 24 or 32 bits files in the hearing frequencies? Amirm explained us he was able to spot the difference in hearing tests, but can it be 'seen' in the graphs?

I can't hear over 15.3KHz, does it make sense to pay for 24bits Hires files? that is my question?!
 

PO3c

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#24
Thanks, I rather have that PCM 44.1 with the 19.4kHz artefact down -110dB rather than MQA with a full spectrum of noise from 16kHz at -96dB. Remember this noise will still be there even when unfolded.
 

PierreV

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#25
So, we can 'see' high frequencies problems with most HiRes files. But can we 'see' (or 'spot') a difference between a 16 bits and 24 or 32 bits files in the hearing frequencies? Amirm explained us he was able to spot the difference in hearing tests, but can it be 'seen' in the graphs?

I can't hear over 15.3KHz, does it make sense to pay for 24bits Hires files? that is my question?!
I think @amirm explained his "trick" on Hi-Res tracks and that it was essentially based on the noise floor. If I remember well, it involved pushing the level way up on silent parts. At least that's how I understood it. That wouldn't be a factor for me as I never was bothered by the CD noise floor.
 

simbloke

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#26
Hi! This videos are very informative! Thanks for all!

I have just downloaded this free tool for linux:

https://www.sonicvisualiser.org/download.html

and I think I've found an ultrasonic pure tone in one of my favorite hi-res tracks. :D
Nice. I just found 29kHz tone in a file I recently extracted from my one and only DVD-A disk (96/24, 2 channel PCM). Hopefully my DAC bothers with sensible filters but who knows.
 

Frank Dernie

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#27
So, we can 'see' high frequencies problems with most HiRes files. But can we 'see' (or 'spot') a difference between a 16 bits and 24 or 32 bits files in the hearing frequencies? Amirm explained us he was able to spot the difference in hearing tests, but can it be 'seen' in the graphs?

I can't hear over 15.3KHz, does it make sense to pay for 24bits Hires files? that is my question?!
The maximum frequency storable is dependant on the sampling frequency not the bit rate. The bit-rate determines the dynamic range.
If you hear to 15.3kHz 44.1 sampling rate will be storing all frequencies you can hear.
IME whilst the "silent" bit between tracks may be more silent with 24-bit than 16 bit I have never seen or heard of a music recording with greater than 96dB of dynamic range, so 16-bit can store all the music from the loudest to the quietest parts.
That means 16-bit is fine for music (unless you want to turn the volume up a lot in the "silence" between tracks where 24-bit will be better) so 44.1/16 can store all audible (by me, and probably you) parts of a music recording.
20-bits of dynamic range may theoretically be used for film sound tracks, but I doubt it ever actually is because if it was almost no domestic system would be able to play it.
 

Frgirard

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#28
Your taste are not my taste. It's not sharable. The measurements are the only thing shareable.
You can measure a wine in is Chimical composition by chromatography. You cannot measure if the win is bad or good.
A speaker you can
 

AudioSceptic

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#29
Another video in this series analyzing objective quality from the label 2L in PCM, MQA and CD. As before, these videos were produced in 2017 although not much has changed since then (other my comment that Amazon did not offer HD content).

I'm starting to wonder if there are any hi-res files from anyone that have anything other than noise above, say, 24k. Even if there are, who can hear that content, assuming their equipment can reproduce it in the first place? It would be good to know if these Linn samples measure up any better <https://www.linnrecords.com/recording-download-format-test-album>

Just think of all the storage wasted on stuff that is either noise or content that no one can hear.
 

xaviescacs

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#32
I'm starting to wonder if there are any hi-res files from anyone that have anything other than noise above, say, 24k.
Earlier in this thread I posted an example of a 88.2 kHz 24 bit track that does, since all spectrum is correlated with the music. I can only see a flaw in the spectrum analysis, namely a pure tone that appears at ~ 23300 kHz that appears when the overall volume is low. I've cheked other files of the same recording and it appears on all of them, so it looks like something inherent to the recording system, since all tracks were recorded in different days, with different orchestrations, etc. It is a recent recording aimed to be published in SACD format, so it would have been a surprise to discover that the half of it is garbage. I've purchased it from Qobuz, by the way.
 

AudioSceptic

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#33
The maximum frequency storable is dependant on the sampling frequency not the bit rate. The bit-rate determines the dynamic range.
If you hear to 15.3kHz 44.1 sampling rate will be storing all frequencies you can hear.
IME whilst the "silent" bit between tracks may be more silent with 24-bit than 16 bit I have never seen or heard of a music recording with greater than 96dB of dynamic range, so 16-bit can store all the music from the loudest to the quietest parts.
That means 16-bit is fine for music (unless you want to turn the volume up a lot in the "silence" between tracks where 24-bit will be better) so 44.1/16 can store all audible (by me, and probably you) parts of a music recording.
20-bits of dynamic range may theoretically be used for film sound tracks, but I doubt it ever actually is because if it was almost no domestic system would be able to play it.
And if it could, would we be able to listen to it without hearing damage? A really quiet room is supposed to be 20-30 dB SPL, so 120 dB (20 bits) added to that gives 140-150. Conversely, if we take 120 dB as the maximum, we wouldn't be able to hear the "bottom" 20-30 because it would be below ambient noise.
 
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#35
So, Amir described that an advantage of DSD is that it pushes noise from the audible band into higher frequencies. So, why not, as a next step in digital mastering, simply filter out everything above ~40-50Kz and then downsample to a lower rate? Or, perhaps that is just how well-mastered music is produced in the first place...? I guess I'm just not following why you would leave all that inaudible high frequency stuff in the file.
 

PO3c

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#36
To a regret, the video record without subtitlings. Tell shortly - what format has won?
For each one of us to decide by looking at the presentation :)

For me clearly MQA can't be fixed. I has crap performance from 15-16kHz.

While hi-res PCM easily can be resampled with a suitable filter and could prove to be the best performer in a presentation like this.

For DSD we can't alter content in the digital domain. Not sure I like to feed all this ultrasonic content to my 100kHz amp.
 

Frank Dernie

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#37
And if it could, would we be able to listen to it without hearing damage? A really quiet room is supposed to be 20-30 dB SPL, so 120 dB (20 bits) added to that gives 140-150. Conversely, if we take 120 dB as the maximum, we wouldn't be able to hear the "bottom" 20-30 because it would be below ambient noise.
Indeed.
And despite enormous excitement about DACs with 120dB SINAD there hasn't been a speaker tested so far capable of exploiting it, and my guess is outside exotics and some studio main monitors there aren't any.
 

voodooless

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#38
my guess is outside exotics and some studio main monitors there aren't any.
Really? Have any links? I doubt that any speaker ever made will be able to hit the CD audio mark SINAD (within halfway decent bandwidth), let alone 120. 80 would already be a major feat. Hell, making a measurement setup that can do that would already be a major accomplishment.
 

Frank Dernie

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#39
Really? Have any links? I doubt that any speaker ever made will be able to hit the CD audio mark SINAD (within halfway decent bandwidth), let alone 120. 80 would already be a major feat. Hell, making a measurement setup that can do that would already be a major accomplishment.
There are a few horns that can reach 120dB,
https://www.genelec.com/1236a and the ilk.
I haven't measured it but I think my Goldmund Epilog 1&2 might and the full Epilog can.
 

voodooless

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#40
There are a few horns that can reach 120dB,
https://www.genelec.com/1236a and the ilk.
I haven't measured it but I think my Goldmund Epilog 1&2 might and the full Epilog can.
Yes, SPL.. that's not SINAD. Compression drivers will probably have around 2% distortion at 120 dB, meaning a 33 SINAD. Cones will do a bit better, but not by much.

1620395583487.png

Thet even spec upto 3% for the compression driver. No idea at what SPL this is speced, I bet it's not 120 dB.
 
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