Do your 96kHz files contain 44.1kHz music?
Oct 2, 2012 at 1:33 AM Thread Starter Post #1 of 19
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This evening, I happened onto a Positive Feedback article by Teresa Goodwin, titled:
 
[size=large]Are Your High Resolution Recordings Really High Resolution?[/size]
 
In the article, Teresa describes how to use Audacity to display a file's Spectrogram and/or plot a Frequency Analysis.
 
It didn't take long for me to discover some surprises among my HDTracks 96/24 downloads:
 
 

 
 

 
 

 
 

 
 

 
Mike
 
Oct 6, 2012 at 12:09 PM Post #2 of 19
Subscribed.
 
Interesting. I haven't taken the plunge and bought anything of HDTracks yet. I would feel a bit cheated though if i had not gotten what i paid for. 
 
Oct 6, 2012 at 12:13 PM Post #3 of 19
Subscribed. Not only do they offer horrible masters, but they're also now gipping customers. Awesome.
 
Oct 6, 2012 at 12:30 PM Post #5 of 19
Quote:
I was under the impression HDTracks were the place to buy?

Well, it is. 
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 But is it. 
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Oct 6, 2012 at 1:31 PM Post #6 of 19
It's a bit of work to check even one track with Audacity, but the five examples I've shown at the top of this thread are the only five tracks I've checked - one track from each of five different albums, but I've downloaded many more 96/24 albums from HDTracks, and frankly, I'm not interested in checking the rest of them. I literally don't want to know about having been ripped off (whether due to malice or negligence), when it's too late to complain - especially having found problems in two out of five randomly selected tracks.  I wouldn't feel prepared to file a complaint with HDTracks until I had expended a LOT of effort checking every last one of them.  
 
What's done is done, but from now on, I'm going to check the first track of every album I download (from any provider of "Hi-Rez" music), as soon as that track completes and the 2nd track starts to come down. I will cancel the remainder of the download, if ever I find another 44.1-kHz file disguised as an 88.2- or 96-kHz file.  I'll then contact the vendor, explain why I cancelled downloading the remainder of the album, and demand a refund.  
 
Checking at the time of download makes a lot more sense than complaining months later, and in truth, I've not brought this to HDTracks' attention, nor given them an opportunity to correct the wrongdoing, because I'm not willing to spend countless hours checking every last track I've ever downloaded from their servers.
 
I intend to continue doing business with them (if they'll have me) because I really do like some of their remasterings, but I'm going to make sure that the butcher doesn't have his thumb on the scale.
 
Ignorance was bliss.
 
Mike
 
Oct 6, 2012 at 2:28 PM Post #7 of 19
Quote:
It's a bit of work to check even one track with Audacity, but the five examples I've shown at the top of this thread are the only five tracks I've checked - one track from each of five different albums, but I've downloaded many more 96/24 albums from HDTracks, and frankly, I'm not interested in checking the rest of them. I literally don't want to know about having been ripped off (whether due to malice or negligence), when it's too late to complain - especially having found problems in two out of five randomly selected tracks.  I wouldn't feel prepared to file a complaint with HDTracks until I had expended a LOT of effort checking every last one of them.  
 
What's done is done, but from now on, I'm going to check the first track of every album I download (from any provider of "Hi-Rez" music), as soon as that track completes and the 2nd track starts to come down. I will cancel the remainder of the download, if ever I find another 44.1-kHz file disguised as an 88.2- or 96-kHz file.  I'll then contact the vendor, explain why I cancelled downloading the remainder of the album, and demand a refund.  
 
Checking at the time of download makes a lot more sense than complaining months later, and in truth, I've not brought this to HDTracks' attention, nor given them an opportunity to correct the wrongdoing, because I'm not willing to spend countless hours checking every last track I've ever downloaded from their servers.
 
I intend to continue doing business with them (if they'll have me) because I really do like some of their remasterings, but I'm going to make sure that the butcher doesn't have his thumb on the scale.
 
Ignorance was bliss.
 
Mike

I know there was the big debacle of certain HDTracks having seriously poor mastering. But then, I've heard the defense that HDTracks
just distributes, they don't have control over the mastering. Which yes, I presume I'm being unreasonable when I want quality control.
 
But then this...I'm not sure how much more blatant things can get. I fear how widespread the problem is. Do you chalk that up to failure of quality
control, or something more...
 
Oct 6, 2012 at 3:25 PM Post #8 of 19
Well, we have no way of judging malice vs. negligence, but even negligence can't be scolded too harshly in a market where no one is complaining.  The distributor has no incentive to spend money on quality control if everyone is blissfully ignorant of quality issues.  
 
I, the consumer, should police the quality of what I buy - I can't expect anyone else to do it for me, not for every product.  Hi-rez music downloads are well beyond the FDA's jurisdiction.. 
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So, let's get off the sofa and start using Audacity to check our downloads as they are being received.  If anyone finds anything, they can post it here in this thread, along with a  happy ending, hopefully, to how the complaint was handled.
 
Mike
 
Oct 7, 2012 at 2:30 PM Post #9 of 19
I've got an HDTracks download in progress, as I'm making this post - their 96/24 Fleetwood Mac Rumours album.
 
Righ as the download of the first track completed, I opened the original FLAC file in Audacity and this is what I found (good news):
 
 

 
I will allow this download to complete.  No complaints...
 
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Mike
 
Oct 7, 2012 at 3:33 PM Post #10 of 19
Download completed. I used Audacity to check the last track, too - Goldust Woman - it's fine.  
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For the record, I timed the operation of opening the FLAC in Audacity, checking it, and then exiting Audaicity...
 
It takes 12 seconds to find out if a 96/24 download actually contains audio frequencies higher than than 22 kHz.
 
Mike
 
Oct 7, 2012 at 10:23 PM Post #13 of 19
All that extra money paying for frequencies you can't hear and you don't get them. . . that sucks. . . but it's also pretty funny. 
 
Oct 8, 2012 at 10:10 AM Post #14 of 19
Quote:
All that extra money paying for frequencies you can't hear and you don't get them. . . that sucks. . . but it's also pretty funny. 

 
LOL!  Within the context of your premise, it is indeed, VERY funny (and sad)!   
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Point   There are audible advantages:
 
Quoting an article at www.masgtering7.com:
 
Why is 96 kHz better?
 
It has to do with the Analog to Digital (A/D) converter. A Mr. Nyquist found out that the sampling frequency of an A/D converter must be twice the audio frequency we want it to convert. Humans hear up to 18 kHz, give or take, unless they have ruined their ears in front of Marshall stacks, 147 Leslie’s and other blasters.
 
So a converter with the traditional 44.1 or 48 kHz sampling rate can convert up to 22.05 of 24 kHz audio, well above what even a newborn can hear.
 
So why 96 kHz is better? To answer this question we have to dig deeper. If an A/D converter receives frequencies that are above the Nyquist frequency (e.g. overtones at 30 kHz) it does not simply ignore them. It ‘folds’ them back into the audible frequency spectrum, resulting in false tones. The solution to this problem is a filter in the analog part of the converter that filters all frequencies above 22 kHz, so they can’t fold back. These filters are called brick wall filters, because they stand there like a brick wall that doesn’t let anything trough. Unfortunately, small portions of the audio are bouncing back from this ‘wall’, creating so called artifacts (turbulence/ distortion) in the high frequencies that are audible. 
 
By raising the sample frequency from 44.1 kHz to 96 kHz (audio from 22.05 to 48 kHz), the filter frequency can be raised too (from 22 kHz to approx. 35 kHz). The filter can be smoother (like tilting the wall). The back-bouncing gets reduced and only affects frequencies above 20 kHz.

 
Quoting another article:
 
Why Record Ultrasonics?
 
As is widely recognized, most of us can ’t hear much above 18 kHz, but that does not mean that there isn’t anything up there that we need to record – and here's another reason for higher sampling rates. Plenty of acoustic instruments produce usable output up to around the 30 kHz mark – something that would be picked up in some form by a decent 30 in/s half-inch analog recording. A string section, for example, could well produce some significant ultrasonic energy.
 
Arguably, the ultrasonic content of all those instruments blends together to produce audible beat frequencies which contribute to the overall timbre of the sound. If you record your string section at a distance with a stereo pair, for example, all those interactions will have taken place in the air before your microphones ever capture the sound.You can record such a signal with 44.1 kHz sampling and never worry about losing anything –as long as your filters are of good quality and you have enough bits.
 
If, however, you recorded a string section with a couple of 48-track digital machines, mic on each instrument feeding its own track so that you can mix it all later, your close-mic technique does not pick up any interactions.The only time they can happen is when you mix – by which time the ultrasonic stuff has all been knocked off by your 48 kHz multitrack recorders, so that will never happen. It would thus seem that high sampling rates allow the flexibility of using different mic techniques with better results.

 
 
Counterpoint   There are no audible advantages:
 
Quoting an Audio Engineering Society report:
 
The authors report on a series of double-blind tests comparing the analog output of high-resolution players playing high-resolution recordings with the same signal passed through a 16-bit/44.1-kHz “bottleneck.” The tests were conducted for over a year using different systems and a variety of subjects.
 
The systems included expensive professional monitors and one high-end system with electrostatic loudspeakers and expensive components and cables. The subjects included professional recording engineers, students in a university recording program, and dedicated audiophiles.
 
The test results show that the CD-quality A/D/A loop was undetectable at normal-to-loud listening levels, by any of the subjects, on any of the playback systems. The noise of the CD-quality loop was audible only at very elevated levels.

 
Mike
 
Oct 19, 2012 at 10:04 AM Post #15 of 19
Here's a great lecture by the CTO of ESS (makers of Sabre DACs), where he says (paraphrasing) that there are things the human ear can hear, which can't be measured - a conclusion that, as an engineer, he accepted with some difficulty.
 
RMAF 11: Noise Shaping Sigma Delta Based Dacs, Martin Mallison, CTO, ESS Technology
 
http://youtu.be/1CkyrDIGzOE
 
Jump in at 00:51:40 (hh:mm:ss) if you don't care to listen to the whole thing.
 

 

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