When you try to explain to people in the comments that they persist in delusion, stories begin that they are great practitioners, you have seen everything on the spectrogram, you cannot be fooled by their “theoretical dregs”. Because of my education, I am familiar with the physiology of hearing, and because of my hobbies, I am familiar with the practice of recording. Under the cut I will try to explain in detail why the stories about “20 kHz in Pink Floyd’s cymbals”, the magical breadth of the range of vinyl records and the ability to hear 20 kHz after 30 years have nothing to do with reality.
Starting with hearing and age-related hearing loss
Everyone knows that a person is able to hear in the range from 20 Hz (according to other sources, from 16) to 20 kHz (according to other sources, up to 21 kHz). However, many people forget that this range decreases over time, and the older you get, the lower the frequencies you can hear. Otolaryngologists, in particular, audiologists, believe that a ceiling of 8000 Hz is the norm and allows a person to live normally (I, of course, would clarify that audiophiles cannot, but audiologists write that 8 kHz is enough). The same audiologists often operate with a simplified age table, where the hearing loss with age is approximately described:
up to 19000 Hz – under 20 years old.
up to 17000 Hz – under 24 years old,
up to 16000 Hz – under 30 years old,
up to 15000 Hz – under 40 years old,
up to 12,000 Hz – under 50,
up to 8000 Hz should be heard by everyone.
These data are rather arbitrary. For example, I am 35 years old and I hear 17,500 Hz, and someone at my age can hardly distinguish 15.5 kHz, and at 16 he can no longer hear anything. On average, for most people, the average threshold value is 16 kHz. Almost everyone rely on this frequency, including sound technicians. But there are also individual characteristics, such as its own frequency response.
Psychoacoustic experiments demonstrate that people do not hear in the same way, and there are individual differences in frequency perception. Sometimes the range can be limited to a frequency of 15 kHz, he does not hear everything higher, but is able, for example, to selectively hear sounds with a frequency of 18.5 kHz. I have not come across an exact explanation of such a phenomenon, but the fact is that it is described and exists.
The intensity of age-related hearing loss depends on a number of factors, and, perhaps, the main one is the regular exposure to noise, as well as loud sounds, trauma, and inflammation. Hearing degradation in modern conditions, to one degree or another, occurs in everyone (at least if we talk about city dwellers), since regular noise exposure affects the ciliary cells of the cochlea.
In addition to noise and traumatic injury, A. Saxen and N. Fiand established other common causes of natural age-related hearing degradation (presbyacusis). Let’s highlight two main ones. The first is a violation of the blood supply to the labyrinth of the cochlea as a result of ischemia (narrowing of the lumen of the blood vessels supplying the cochlea), disturbance of blood circulation can also contribute to changes in the rheological properties of blood (including thrombosis), atherosclerosis, etc.
As a result of such disorders, the hair cells of the cochlea (auditory receptors) experience oxygen starvation, the function of the receptors is impaired. Sometimes there is local cell death – necrosis, which leads to significant hearing loss. But more often the correct transformation of sounds into electrical impulse and synaptic processes of the nervous tissue is simply disturbed, on which the transmission of information to the centers of hearing in the cerebral cortex depends.
The second is degenerative processes in nerve cells, which have not been sufficiently studied today to draw conclusions about their mechanisms. At the same time, it is known that with neuronal degeneration, there is not only a change in the electrical characteristics of the impulses generated during impaired functioning of hair cells (as a pathologically altered response to sound stimulation), but also problems with the speed of signal processing in the central nervous system, which today are considered the main cause. narrowing the range.
It has also been proven that the effect of age-related narrowing of the frequency range is characteristic of all people, the difference is only in the speed of the onset of changes. The latter, with a high probability, is determined individually (by the characteristics of the nervous tissue, quality of life, third-party negative influence). Meanwhile, audiologists and psychoacoustics specialists note a decrease in the upper limit of the frequency range by at least 1 kHz every 8-10 years (which is quite consistent with the approximate figures given above).
Those. even if we assume that someone was able to halve the speed of this process in comparison with that noted in the studies (this is not described in the literature, but hypothetically imagine), then by the age of 30 such a hypothetical person, with all his might, will not be able to hear outside 18500 Hz. A reservation should be made here about the phenomenon of selective sensitivity to specific high frequencies, which does not affect the picture as a whole. At the same time, all this time he must live in the countryside, and preferably in the forest, and carefully protect his hearing from strong irritants that can accelerate degenerative processes.
In order to assess your own hearing, I recommend using online generator… It is also important to use headphones (acoustics) that are able to accurately reproduce these frequencies. Some unscrupulous little-known manufacturers of budget sound-reproducing devices sometimes overestimate the reproduced range in order to show beautiful numbers.
Conclusion 1: Thus, aging audiophiles talking about insufficient “air” “at the cymbals” at 20 kHz and a dip at 24 kHz is a picture for a humorous show. Well, or a subject of interest for a psychiatrist, auditory hallucinations about frequencies that a person is physiologically unable to hear is a symptom.
A little about instrument frequencies
There is enough information on the network about the frequencies of the sounding instruments, including various overtones, overtones and other nuances. Sound engineering textbooks also abound in such information. Interestingly, nowhere, except for a couple of phylophonistic forums, there is a different view of the frequencies and overtones of instruments (the difference in overtone estimates does not exceed 1 kHz).
One of the arguments of audiophiles for the need to reproduce 20+ kHz often goes like this: “The range of cymbals overtones (hi-hat, crash, ride, chin, etc.) ends outside 20 kHz.” The reality is strikingly different from this representation, so, without exception, all sources describing equalization and the range of percussion instruments (except for 2 audiophile forums on the Russian Internet) give the following information (I took the maximum values found):
the range of standard cymbals, as a rule, is not defined, depending on the type of sound production and the size of the cymbal of a standard kit (hat, crash, ride, chin) they are capable of sounding in the range from 300 – 10,000 Hz, “air” to 15,000 Hz.
Orchestral cymbal equalization has more precise values:
The range is also not accepted
Orchestral cymbal horn 220 Hz (with overtones up to 3.5 kHz)
Clarity 7.5 kHz
Air 10 kHz -13 kHz
All rare percussion cymbals and non-standard cymbals also stay within these values. In addition to “experts” from audiophile forums, there is no mention of the fact that cymbals can give “air”, let alone overtones above 15 kHz.
For the sake of fairness, it should be noted that there are instruments that are capable of producing overtones above 16 kHz, these are:
- violin piccolo overtone up to 18000 Hz
- flute piccolo overtone up to 17000 Hz
- human voice (Coloratura soprano) overtones up to 16500 Hz
These are the maximum values found in the authoritative literature. At Aldoshina in “Fundamentals of Psychoacoustics”, materials www.otsema.ru, zwook.ru and others, almost everywhere the frequencies are indicated below, but I take the maximum possible.
Conclusion 2: “Plates fly away easily above 20k” – do not fly away.
A little about vinyl
I will not dwell in detail on why the recording has no chance in competition even with mp3 320 kb / s in terms of fidelity of reproduction, when comparing objective parameters I will not. I can only remind you of detonation, poor dynamic range, limitation on recording low frequencies, as well as recording them in mono, and in the area in which it is already possible to localize the low frequency source, as well as the recording limit in terms of signal-to-noise ratio.
The question is solely about the frequency range of records on vinyl records. If we are talking about old gramophone records released during the heyday of the industry (60s, 70s, 80s), then, at the mastering level, the frequency is limited to a maximum of 20 kHz, sometimes 16 kHz. In any case, the RIAA standard does not imply frequencies beyond 20 kHz in recording (until 1978, the standard guaranteed 15,000 Hz). “Where, then, on the spectrograms of vinyl high-rips, flying away in the distance peaks at 100 and 200 kHz?”, Ask inquisitive audiophiles.
And they will begin to refer to magic plates, from above the sensation of high frequencies and golden ears, capable of determining the “air” at frequencies outside, determined by the narrow-minded physicists and audiologists.
The answer to this question is very simple. This is nothing more than harmonic distortion, which appeared when digitizing vinyl. Due to the “high-res” format, the distortions remained in the frequency spectrum at which the high-res was designed. The original production simply did not have these ultrasonic components, at least because the master tape with which the vinyl was recorded has frequency limitations.
The mythology of the ultra-high range of records on records echoes the data that it is possible to record ultrasound on vinyl with a frequency of up to 100 kHz. This is indeed the case, for example, quad recordings of the late 70s were made by recording using signal modulation at frequencies above 40 kHz. For this, and not for unknown spatial effects, the frequency range of the cartridges was increased and needles with shibata sharpening were used.
Conclusion 3: The upper limit of the frequency range of recordings on vinyl until the 70s (before the appearance of the RIAA-78 standard) is rarely above 15 kHz, for the 1970s – 80s, at best, it reaches 20 kHz, at first listening.
In the dry residue
The conditional ceiling that a person is able to hear is slightly higher than the real plus or minus by 3-4 kHz. Thirty – forty-year-old people who claim to be able to hear 20 kHz are most likely lying or mistaken (I admit an extremely unlikely casuistic single case). Overtones above the threshold of 15, 5 – 16 kHz have only 3 instruments (piccolo violin, piccolo flute, human voice – coloratura soprano, there is no recorded case that the overtones of these instruments (sounds) reach 20 kHz (18 kHz ceiling for the violin The records released from 1952 to 1978 do not guarantee a frequency range of 20 kHz, they have a ceiling of 15 kHz defined by the standard. It is to this period that the so-called reference albums of Pink Floyd, about which they love so much, belong to reason audiophiles.
There really is a technical sense in extending the reproducible frequency range beyond the audible frequency spectrum in speakers and headphones. But this is not an attempt to convey the “metaphysical features of music” in a way unknown to science, but a known way to improve the transient response, which is not as obvious as the frequency response, but strongly affects the fidelity of reproduction. It is for this reason that many studio monitors and expensive hi-fi speakers have a declared upper frequency range that is much higher than the conventionally audible 20 kHz.
Please share in the comments, what is your high-frequency perception threshold. Let me remind you that the generator can be found here. onlinetonegenerator.com