Hi-Fi - the problem of classification: about history, standard, marketing and terminology

    This post has been brewing for a long time, and its content is largely dictated by discussions that often arise in comments, consumer disputes, as well as trading floors. In the majority view, the concept of Hi-Fi for audio equipment means some abstract high class technology. This notion of high quality or class rarely correlates with specific specifications, technical values ​​and standards.

    Some audio manufacturers, often intentionally, refuse to use the term “Hi-Fi” when positioning their products. Others, on the other hand, tend to mention more often that a device belongs to Hi-Fi. Under the cut, I will talk about the history of the term, that today it has the right to be called “Hi-Fi” in accordance with recognized standards, why manufacturers deny it.

    A bit of history

    The overwhelming majority know that “Hi-Fi” is short for High Fidelity — that is, high fidelity. This implies a high fidelity playback. Thus, we can conditionally understand a certain class of devices as Hi-Fi devices, the playback fidelity of which is higher than that of ... higher than that of the abstract majority of others.

    The phenomenon itself is older than the term, since almost always the devices were a little better and a little worse. At the dawn of the appearance of audio recordings and equipment for their reproduction, it was difficult to determine where fidelity is higher, but in 1924 the second most significant event occurred after the appearance of Edison's phonograph. Sound recording has become electric. We can say that it was then that the first Hi-Fi appeared.

    The fact is that the recordings made with the help of an electric recorder were of higher quality than those recorded with the help of mechanical phonographs, which can already be considered a reason to divide the devices into classes. Thus, the year of birth of Haifa can be considered the 1924th, when Bell Telephone Laboratories developed a recording using a primitive carbon microphone, a tube amplifier and an electromechanical recorder.

    At that time, the main technical parameter that determined the fidelity of reproduction was considered to be the frequency range. Already by 1929, it had reached 50–6000 Hz for electromechanical devices, and by the mid-30s, it had gone beyond 30–8000 Hz. The level of distortion gradually decreased and the dynamic range of records increased.

    New recording quality characteristics required new features from reproducing equipment. Records were the most common sound carrier in those years, thanks to the appearance of electrophones in the early 30s, they were able to achieve high-quality reproduction. There are new heads of type MM (moving magnet). At about the same time, it began to be actively developed, and in Germany even magnetic sound recording was being introduced.

    In the 1930s, significant changes also affect sound emitters, and developments in the field of electrodynamic drivers are particularly active. And so, in 1932,
    for the first time, the term “Hi-Fi (High Fidelity), which implies high fidelity of reproduction , was used by the engineer Hartley for the first time by a manufacturer of speakers using a permanent magnet .

    Obviously, the author did not think that his marketing move would become not only a commonly used cliché, which means quality, but also a standard that guarantees it.

    As time went on, the quality of the equipment grew, and by the end of the forties, the term was gradually used in advertising by various British and American companies, as well as in the media. This period coincided with another leap in the development of fidelity sound reproduction and came at the end of the 40s - the beginning of the 50s:

    • first Long Play (LP) 33 rpm vinyl records and electrophones for listening to them were developed and serially released;
    • began mass production of reel tape recorders;
    • Started serial production of dynamic loudspeakers;
    • lamp amp designs were improved;
    • FM radio appeared, broadcasting began in the VHF band, which guaranteed less interference and wider bandwidth.

    In the 50s, stereo recordings began to be more active, and by the 60s they began to appear en masse on vinyl, which almost completely replaced shellac. It was during this period that the hi-fi of the marketing term begins to turn into a standard. At first it was some generally accepted notions about quality at the moment. By the 70th, a concrete idea of ​​what exactly could be called “high fidelity” was finally formed, and this is how Hi-Fi became the standard.

    Hi-Fi as standard

    The first and so far the only successful attempt to determine the fidelity of reproduction was DIN45500 - a standard issued by the German Institute for Standardization (Deutsches Institut für Normung). The criteria for a new standard for sound-reproducing equipment are:
    • non-uniformity of the amplitude-frequency characteristic (AFChDB);
    • frequency range;
    • nonlinear distortion factor or harmonic coefficient (SOI or Kg,%);
    • signal to noise ratio (signal / noise, dB).
    In accordance with the standard, they have the right to wear the proud name of a Hi-Fi device with the following characteristics:

    Speakers and headphones

    • Nonlinearity of the frequency response relative to the average sound pressure level in the range of reproducible frequencies 100-4000 Hz, dB - ± 4 dB (+ 4 / -8 dB);
    • Nonlinear distortion factor at reproducible frequencies of 250–1000 Hz (2000 Hz), no more than 1%;
    • Nonlinearity of the frequency response in the range of reproducible frequencies of 40—16000 Hz - 1.5 dB at the linear input (2 dB with the presence of a corrector);
    • Nonlinear distortion coefficient in the range of reproducible frequencies of 40–12,500 Hz, no more than 1%.
    • The coefficient of intermodulation distortion in the reproduced frequency band of 250–8000 Hz (also outside this band while reducing the sound pressure level by 6 dB), no more than 3%;
    • The variation of the parameters of channels in the range of reproducible frequencies, no more than - 3 dB;
    • Band of reproducible frequencies, 30 Hz - 15 000 Hz (it is difficult to get higher boundaries, due to the need to suppress the 19 kHz pilot tone)
    • Nonlinear distortion factor at a frequency of 1 kHz, no more than - 0.5%;
    • Difference of parameters of channels in the band of 250–6300 Hz, no more than –3 dB;
    • Transient interference at frequencies of 250–6300 Hz (6300–15000 Hz), no more than 26 dB (15 dB).
    In the future, DIN45500 in almost unchanged form became the EU standard IEC 60581, and in the USSR similar GOST 24388-88 (for UMZCH) and GOST 23262-88 (for AC) were adopted.

    Criticism and standard now

    Almost immediately after the appearance, the standard was subjected to criticism, as it did not contain norms for a number of characteristics essential for sound. The standard does not mention intermodulation distortion, dynamic range, signal-to-noise ratio, damping factor, impulse and transient characteristics, as well as many other measurable parameters. Engineers criticized him for this. Some manufacturers, by contrast, blamed for unnecessary rigidity.

    Unfortunately, these characteristics can not be considered a benchmark, especially in our time. Already at the time of occurrence, many devices exceeded the norms of the standard (for example, products of Japanese companies Nakamichi, YAMAHA, SONY), and today almost every product from semi-handicraft workshops of the PRC corresponds to it. Obviously, if the inhabitants of the Middle Kingdom, who own the basement manufactures, knew the norms of this standard, then the Hi-Fi inscription would decorate all their products with AliExpress.

    It is because of the loss of credibility of the standard, some manufacturers try to ignore the term itself. The most courageous and arrogant refer their products to the High End marketing class, others avoid mentioning classes altogether and simply strongly praise the device, the breadth and depth of the scene, the velvety bass and articulation of high.

    Meanwhile, in the subjective perceptions of consumers, the “real” Hi-Fi is still a technique with high (by modern standards) fidelity. As practice shows, the limit of such fidelity will come only when the work, played live, will be impossible to distinguish from the record.

    In my opinion, the situation could be solved by a new standard that meets the requirements of the times. Such a standard would define the criteria for new Hi-Fi devices, for example, bit width and sampling frequency of DACs, data transfer standards for wireless audio devices, would close the gaping holes in normalizing intermodulation distortions and other psychoacoustically significant characteristics. But so far there is no such standard.

    Blind and non-blind tests

    In connection with the apparent obsolescence of DIN45500 standards, some of the manufacturers and users consider objective review and live tests important. All of them can be divided into two conditional categories, those who prefer to see what is listening and those who trust the double blind.

    At zero, a global scale stacked holivar erupted relative to double-blind testing. Robert Harley and John Atkinson, from the audiophile edition of Absolute Sound, argued that blind tests “do not give a real picture” and that “... substantially distort the listening process and are useless in determining fidelity to play.”

    Editor of the authoritative German publication Soundstage, Doug Schneider, with his articles from 2009, completely refuted the conclusions of the authors of Absolute Sound, stating in particular that: "Blind tests are the basis of ten years of research in the field of loudspeaker design." Today, many blind manufacturers use double-blind tests, including Axiom, Energy, Mirage, Paradigm, PSB and Revel. The only problem is that blind tests are a step back to the definition of high fidelity “by eye”, like the 50s - 60s.


    Unfortunately, the emergence of a new HI-FI standard today is an unlikely story. It is not interested in a huge number of manufacturers who understand that the introduction of standards will affect the cost of production, which any manufacturer would like to reduce. Consumers need to rely on their own ears and accuracy of information in specifications, as well as the great “magic” power of the double-blind method. I would be grateful for your opinions in the comments, describe your custom impressions of the components of the class Hi-Fi, write, do you think there is a need for a new Hi-Fi standard.

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