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Post by liffy99 on Dec 3, 2019 13:20:57 GMT
Hi Martin. I would disagree - a 12 bit recording WILL capture the fidelity of your analogue source. But it will just have a higher, probably unacceptable, noise floor. I appreciate you suggest listening to various recordings and different formats but simply doing that does not show whether they are any better or worse than, say, 16 bit versions. They have probably been remastered to aff3ct their tonal balance, loudness etc. You can ONLY come to a reasonable conclusion by listening to different resolution versions of the SAME recording. I will dig out the web links to the sources I have mentioned before. Pop over to Glastonbury and let’s see if either of us can tell the difference between 16 and 24 bit !
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Post by liffy99 on Dec 3, 2019 13:38:02 GMT
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Post by MartinT on Dec 3, 2019 14:55:22 GMT
You can ONLY come to a reasonable conclusion by listening to different resolution versions of the SAME recording. I've done that in the past with test files of the same music at different resolutions, but I agree that it's all subjective. I'm hoping someone will come along and explain why the theory of 70dB or so dynamic range for an analogue tape does not map to what I hear in a well mastered digital transfer.
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Post by petea on Dec 3, 2019 15:29:49 GMT
Interesting. I had just watched that video and it helped explain a couple of things that I was struggling with, especially transients. My knowledge of A/D is in optics and I think therein comes a problem as the conversion process is very different, but often (incorrectly) used as an analogy. I also read the article that lead me to the link that you also give. And it was in that that I read some points that might help to explain what I have heard (and possibly therefore misinterpreted).
The example was a demonstration of recordings made (or at least sampled at) different bit-depths and sampling frequencies from a single master. The purpose was to show off file-based audio and to try and sell you a Melco music server (I ended up buying one from their main competitor for both technical and aesthetic reasons and not because of the slightly annoying presentation / presenter!). During the demonstration it was clear that vocals especially became more nuanced as the bit depth / sampling frequency increased. It was fairly subtle, but it was there. Given the above, why was that? One point made in the article was the perception of differences as small as 0.2 db. Could the D/A reconstruction at the higher frequency (even if only for certain waveforms) have caused minute volume changes that affected ones perception (or, if one is cynical, were the high rate/depth files recorded with more gain!)?
The other thing that came from the article was the presence of frequencies above the audible spectrum in high rate/depth files causing distortion. Opting to exclude them was considered the better option although as long as one's amplification and speaker setup etc could handle those and prevent them doing anything other can reproduce 'natural' harmonics then that seems also to be a valid option. - the way that super-tweeters seem to affect lower frequencies in the way they do seems to fit the 'taking the strain off' theory I guess. And while on that subject, there is a flaw in his visible spectrum / audible spectrum analogy I think. It is correct that one cannot see IR, but you can feel it - in the same way one cannot 'hear' certain frequencies, but you can feel them and in some studies on UHF, subjects do respond to frequencies well out of the range of audibility, and so I do not think that they can be discounted completely (of course whether one can reproduce them or their affect is another question - and were there there in the recording and from the musical performance?).
Something else that has been buzzing around in my head for a few weeks has been a comment someone made on the forum about hearing something new in a recording as a result of a change made and then not being able to un-hear it when they switched back. I can think of several instances where that has happened, but usually hearing something 'new' when my system was 'improved' in its resolving power and then finding I could hear this new revelation using another, less 'capable' system, after. I could hear it because I know it was there? And which version was correct in the first place? And was it sampling rate / bit depth, overall resolution etc the cause?
Anyway, thanks for posting these thoughts and links. Really interesting stuff I think.
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Post by liffy99 on Dec 3, 2019 19:31:05 GMT
Good reply and yes, possibly, harmonic impact of uhf may, just, be sensed by the body outside of our normal range of hearing. Who knows. But even so, the differences must be so vanishingly small I doubt they could really impact the musical enjoyment. Of greater impact is probably the various forms of ‘placebo’ effect - e.g. I have just put a better (more expensive ?) cable in so it must sound better. Whilst comparing a number of 16/44 and 24/96 tracks from the same source I also struggled with the comparison method. For instance I would listen to track A, then track B, and more often than not, prefer the latter. Then it dawned on me that once I had listened to track A first, I was more aware of what I was listening to in track B (I.e. actively looking to find a difference). So then I started listening to tracks in random order - A then B, B then A etc. But even then I seemed to prefer the second track. At the end I am convinced I cannot, with any reliability, tell the difference. If there are differences they are so tiny as to be irrelevant.
On a side note, anyone know the S/N ratio of studio quality tape decks ?
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Post by petea on Dec 3, 2019 19:57:01 GMT
A Studer A820 in 2 track mode at 30 ips using 1/2" tape was quoted at 77 dB. I have a couple of Nagra IV-S field recorders and they are about 70 dB at 7.5 ips. I've never seen figures quoted for 15 ips though.
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Post by liffy99 on Dec 3, 2019 22:35:17 GMT
Thanks. So a 13 bit equivalent (78dB) is about as good as tape gets then. Any ‘details’ captured below this level will simply be masked by the noise.
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Post by MartinT on Dec 3, 2019 22:35:57 GMT
Of greater impact is probably the various forms of ‘placebo’ effect - e.g. I have just put a better (more expensive ?) cable in so it must sound better. . . . Then it dawned on me that once I had listened to track A first, I was more aware of what I was listening to in track B (I.e. actively looking to find a difference). So then I started listening to tracks in random order - A then B, B then A etc. But even then I seemed to prefer the second track. There is no placebo effect if you don't want there to be one. I am ruthless with evaluating my equipment and have moved many things on that didn't work out. I have no need to kid myself and completely reject this placebo effect nonsense. A/B listening is fraught with issues, not least that you're actively trying to hear a difference. Things don't work like that. Better to make a change, relax and spend the entire evening listening to the changed setup. Then revert the following evening. You will soon become aware of differences, if any. If you hear no difference over a prolonged period, then the change has no effect. A/B listening ruins any possible enjoyment of the music and therefore the purpose of making the change in the first place.
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Post by MartinT on Dec 3, 2019 22:39:19 GMT
Thanks. So a 13 bit equivalent (78dB) is about as good as tape gets then. Any ‘details’ captured below this level will simply be masked by the noise. I still don't agree. You can utilise more bits to resolve all the levels above the noise floor up to the ceiling level. If you use 24-bit encoding, for instance, you may well burn 4 bits on the noise but you'll still be using 20 bits on the music signal.
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Post by liffy99 on Dec 5, 2019 9:19:22 GMT
This is a really interesting conversation, so hope you don’t mind the exchange. I may seem a bit (excuse the pun) of an evangelist on this one but A chief concern is why are we being overcharged for wholly unnecessary ‘hi res’ recordings ? Understanding how digital audio works can save you money ! Martin, you still seem to believe that more bits equals greater resolution. It does not,. This is a mathematical fact. When you increase bit depth sure, you are improving the ability of each sample to get closer to the actual value of an analogue waveform. Given that the an analogue signal is highly unlikely to ever correspond to a fixed bit number (e.g. it may fall between 0101100110001110 and 0101100110001111) the difference to the nearest digital value is called quanization error. This error manifests as unwanted noise and has no effect whatsoever on the fidelity of the waveform. It is simply noise that is far, far below the music signal and hence sets the threshold of the possible sn ratio ( and therefore dynamic range). We can discuss the effects of dither, and the benefits of 16 or 24 bit files, but noise levels are already so vanishingly low in red book as to be inaudible, especially against the ambient noise level in your room. Please note that there is no commercially available DAC on the market today capable of better than 21 bit capability, and the rest of our systems, it is probably a bit less than that. We have not touched on sampling rates (which determine the frequency response) and I accept there may have been issues with early anti-aliasing designs where some ultrasonic frequencies could leak back into the audio band (see anti-aliasing) but DACS and ADCs are much better these days. The following explains it better than www.head-fi.org/threads/24bit-vs-16bit-the-myth-exploded.415361/As you say, long term listening is probably better than back to back comparisons as we are psychologically unable to dismiss the placebo efffect entirely. Even the order in which we listen to comparison tracks can influence our perception. In any case, the differences we are discussing here, if they exist at all, are so small as to be not worth worrying about. By the way, I am no expert in all this stuff but sad enough to enjoy reading about it. And the proposition that 24 bit audio is just not worth it has been borne out by my ears / system to my satisfaction. Time to organise a double blind test perhaps ?.?
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Post by MartinT on Dec 5, 2019 9:49:27 GMT
Not quite: more bits can more closely track the resolution of an infinitely varying waveform.
One key question is: what is the 'resolution' of an analogue master tape? Don't be too quick to answer that one!
If I fail to explain something in my mind I keep on thinking about it. I know that higher resolution music *can* sound better, so I need a theory to fit it. I am not sure whether quantisation noise is quite as benign as you suggest and that the waveform characteristics 'lost' between two data points are more significant than first seems. However, I suspect that it all matters.
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Post by John on Dec 5, 2019 10:24:29 GMT
Having a chat with a friend about what is important in bringing you a better sound Higher bit rate files or better jitter control I think jitter is far more important
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Post by petea on Dec 5, 2019 10:54:32 GMT
Worn out after Page 6!
Interesting stuff though again and what I am getting from this is that if one does hear differences between 16 and 24 bit depth files it is more likely to be how the 16 bit file was created from the 24 bit master. So, assuming storage is not a problem for files or that bandwidth is not an issue when streaming, then a 24 bit file might be 'safer' / closer to the master than a 16 bit one (that assumes that the file / stream is of course not an up-sampled version of a 16 bit or lower file - I think HiResAudio are still the only bunch auditing every file they are presented) even though, in many cases there would be no audible difference The next issue of course is sampling frequency. Ignoring artefacts and other factors then, at least in theory, the higher the sampling frequency the better one would be able to 'record' transients and separate complex spectral mixtures. The penalty is of course file size and there will be a point at which any benefits become too small to be detected.
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Post by Deleted on Dec 5, 2019 11:01:01 GMT
Here's a thought for you, can your system actually resolve the 'extra' resolution first before passing comment? Straightforward thoughts here. Think of the bit rate as the size of the window, the sample rate as the amount of information that is captured in that window. If you a window a size that is 16 x 16 (red book 16 bits, 441000 samples per second), now this is a log scale not a linear scale, also a window 24 x 24 (still say 44100 samples per second)if all things being equal and you recorded a track with both formats identically using the same equipment according to the theory they should sound the same yes? Have any of you actually been able to do this at all? I am not knocking red book at all it can sound rather decent, in fact 80% of our demo's are with the read book format. However we record in various formats in our studio, most common is 24/96 or 24/192, for me personally I prefer a direct multiple of red book, my personal two most used are 24/176.4 and 32/352.8Khz. Can you discern them in an A/b test? a deaf monkey on speed could without question. This is for the non closed minded little individuals that model themselves on Napoleon who feel because there lot in life is not what it should be then by attempting to piss on everyone else's bonfire it gives them self satisfaction from the limited power job during the mundane working week. I will clarify this for you, the biggest single impact on the quality of sound regarding what ever format you play it on relies on two very critical procedures. The initial recording engineer has taken the time to set up the recording space correctly for the needs of each artist / orchestra / band, he or she has a passion for their work IE in making sure that the customer has the best possible sounds for their individual circumstances and the set up, mic placement, recording systems is fully optimized whether digital or analogue. Two in the mastering and transfer process the same care and attention is shown 100% Every wondered why some CD sound amazing and others are fit for beer mats, likewise some vinyl is only fit for a Frisbee! If these rules are adhered to then you will obtain very decent results, these days many records are made sweet-wise or for the mass radio edit market neither of which give rise to true sound quality imho. However it serves the masses well Our studio Studer 810 recorder we usually use either 15ips for high quality general recording around 70dB or for delicate coral, strings/piano and light jazz work 30ips (better mid band and top end) but the bass roll off at the bottom is around 30Hz though this does equate to a s/n of very close to 74dB. All of this is pretty superfluous unless the chain of recording has a quality assurance which stems from plugging in the first connection to the last fade on mastering finalizing. Some bits are just added random noise I would agree, however a genuinely recorded 24/96 or which ever format you wish done correctly and played back through a capable system will deliver a sound with greater stage depth, three dimensionality, improved spatial separation and a greater sense of ease and fluidity. No need to get into here, just bask in benefits of what is possible now
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Post by MartinT on Dec 5, 2019 12:52:40 GMT
Having a chat with a friend about what is important in bringing you a better sound Higher bit rate files or better jitter control I think jitter is far more important I agree completely!
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Post by jandl100 on Dec 5, 2019 13:17:30 GMT
There is no placebo effect if you don't want there to be one. I am ruthless with evaluating my equipment and have moved many things on that didn't work out. I have no need to kid myself and completely reject this placebo effect nonsense. Woof! That stopped me in my tracks. Placebo effect isn't a matter of choice, it's subliminal. Who knows what is going on in their subconscious? You'd need to be a robot to evade Placebo's clutches - even then the robot will be influenced by the conscious and subconscious biases of the people who programmed it.
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Post by liffy99 on Dec 5, 2019 13:26:24 GMT
Here's a thought for you, can your system actually resolve the 'extra' resolution first before passing comment? Straightforward thoughts here. Think of the bit rate as the size of the window, the sample rate as the amount of information that is captured in that window. If you a window a size that is 16 x 16 (red book 16 bits, 441000 samples per second), now this is a log scale not a linear scale, also a window 24 x 24 (still say 44100 samples per second)if all things being equal and you recorded a track with both formats identically using the same equipment according to the theory they should sound the same yes? Have any of you actually been able to do this at all? I am not knocking red book at all it can sound rather decent, in fact 80% of our demo's are with the read book format. However we record in various formats in our studio, most common is 24/96 or 24/192, for me personally I prefer a direct multiple of red book, my personal two most used are 24/176.4 and 32/352.8Khz. Can you discern them in an A/b test? a deaf monkey on speed could without question. This is for the non closed minded little individuals that model themselves on Napoleon who feel because there lot in life is not what it should be then by attempting to piss on everyone else's bonfire it gives them self satisfaction from the limited power job during the mundane working week. I will clarify this for you, the biggest single impact on the quality of sound regarding what ever format you play it on relies on two very critical procedures. The initial recording engineer has taken the time to set up the recording space correctly for the needs of each artist / orchestra / band, he or she has a passion for their work IE in making sure that the customer has the best possible sounds for their individual circumstances and the set up, mic placement, recording systems is fully optimized whether digital or analogue. Two in the mastering and transfer process the same care and attention is shown 100% Every wondered why some CD sound amazing and others are fit for beer mats, likewise some vinyl is only fit for a Frisbee! If these rules are adhered to then you will obtain very decent results, these days many records are made sweet-wise or for the mass radio edit market neither of which give rise to true sound quality imho. However it serves the masses well Our studio Studer 810 recorder we usually use either 15ips for high quality general recording around 70dB or for delicate coral, strings/piano and light jazz work 30ips (better mid band and top end) but the bass roll off at the bottom is around 30Hz though this does equate to a s/n of very close to 74dB. All of this is pretty superfluous unless the chain of recording has a quality assurance which stems from plugging in the first connection to the last fade on mastering finalizing. Some bits are just added random noise I would agree, however a genuinely recorded 24/96 or which ever format you wish done correctly and played back through a capable system will deliver a sound with greater stage depth, three dimensionality, improved spatial separation and a greater sense of ease and fluidity. No need to get into here, just bask in benefits of what is possible now Hmm, not sure I follow all this as the spelling and grammar are so weird that making sense of your statements is difficult. Nor do I appreciate you rather unnecessary comments in the 8th para. if I get your gist though, I fully agree that the quality of the recording and mastering pretty much trumps anything else down the line. And sure, there is a demonstrable place / need for high bit depth and sampling frequencies in the mastering studio. But I would challenge anyone to tell a difference between 16/44 and 24/96 versions of the SAME track (ie with identical mastering and recording ). Why not sign up for Mark Waldrep’s HD Challenge and share your results ? I would have no objection to any of us buying and storing Hi Res files as storage is cheap now and download speeds pretty fast - as you say, if it does no harm why not ? But that’s the issue - it DOES do harm in that we are charged extortionate amounts for no perceivable benefit (let alone distributors passing off red book recordings as high res just because they have been upsampled to a higher bit rate etc). its all just a marketing scam. Anyway, I don’t have a big enough window. Time to get my coat methinks . . .
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Post by liffy99 on Dec 5, 2019 13:29:48 GMT
There is no placebo effect if you don't want there to be one. I am ruthless with evaluating my equipment and have moved many things on that didn't work out. I have no need to kid myself and completely reject this placebo effect nonsense. Woof! That stopped me in my tracks. Placebo effect isn't a matter of choice, it's subliminal. Who knows what is going on in their subconscious? You'd need to be a robot to evade Placebo's clutches - even then the robot will be influenced by the conscious and subconscious biases of the people who programmed it. Getting paranoid ? 😁
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Post by MartinT on Dec 5, 2019 13:56:30 GMT
That stopped me in my tracks. Placebo effect isn't a matter of choice, it's subliminal. Not if you're evaluating a component and genuinely want to know whether there is an improvement or not! There is no place for 'expectation bias' or placebo, it's a matter of keeping an open mind and just listening for the outcome.
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Post by Deleted on Dec 5, 2019 13:57:25 GMT
Hmm, not sure I follow all this as the spelling and grammar are so weird that making sense of your statements is difficult. Nor do I appreciate you rather unnecessary comments in the 8th para. if I get your gist though, I fully agree that the quality of the recording and mastering pretty much trumps anything else down the line. And sure, there is a demonstrable place / need for high bit depth and sampling frequencies in the mastering studio. But I would challenge anyone to tell a difference between 16/44 and 24/96 versions of the SAME track (ie with identical mastering and recording ). Why not sign up for Mark Waldrep’s HD Challenge and share your results ? I would have no objection to any of us buying and storing Hi Res files as storage is cheap now and download speeds pretty fast - as you say, if it does no harm why not ? But that’s the issue - it DOES do harm in that we are charged extortionate amounts for no perceivable benefit (let alone distributors passing off red book recordings as high res just because they have been upsampled to a higher bit rate etc). its all just a marketing scam. Anyway, I don’t have a big enough window. Time to get my coat methinks . . . Hello Iffy No need to get your coat really, first up paragraph 8 wasn't directed at you in anyway more so other folks from other places. Never really been a grammar or structured sentence manufacturer, too many thoughts inside grey matter and trying to get them down in some from of order has never been a strong point for me Mark W I respect a great deal, even co-funded his book (Music and Audio) a few years ago even though he was a year late getting it out! Which I thoroughly recommend. Also I have hard copies of those tracks in both sample rates plus a great deal more of the unavailable MW recordings from AIX records. Even attended one of his lectures a few years ago, he also asked myself to find him a few places to lecture while he was in the UK a few years as well, he is not universally liked in the audio industry because he speaks a lot of truth especially when it comes to MQA I will happily welcome anyone here to take the challenge for themselves no problem at all. You can bring you own SPL meter or use our calibrated one. I also agree with the issue of using high sample rate files and calling them red book, all of our demonstrations CLEARLY show sample and bit rate in the player window while the song is playing. I know a couple of those that do this. Regarding the price of High Rez material, its the same as when SACD was released the latest thing new thing, so there will be people prepared to pay a premium for this always will be no matter what the 'latest and greatest is' not just audio, the choice is down to the individual nothing more. So do not leave the thread its a good one
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