• What is HMLAB ?

  • HMLAB is working with gThe study group of the Technology on the deep senseh. The study group endeavors to discover necessary physical factors and characteristics for a high-fidelity-reproduction of very high quality deep music playing and artistic media. During the studies they want to come closer to how one want to have communication beyond time and space, that is, gCommunication Lab. on Deep senseh.

    HMLAB develops high quality Audio-Visual Systems which implement the discovered research results and sell them.

    We have accomplished a big project aiming the gMerge of Engineering and Artsh (JSPS-RFTE 97P00601, 1997-2001), which is Multimedia of program for the promotion of scientific research with a view to creating intellectual resources of Japan Society for the Promotion of Science.
    To develop further and to return successful results to the general public, we have started HM LAB (High Quality Media Laboratory) which is a venture company starting from JAIST (Japan Advanced Institute of Technology).
    In 2014, we have changed the organization; The research is by gThe study group of the Technology on the deep senseh, and HMLAB supports it.


  • What is "Particular" ?

  • 1. Introduction

    In the case of sound, when we listen to a reproduction of a great music playing by an electric sound apparatus, we hope real and deep admiration in our mind. To arouse deep gadmirationh in onefs mind, gpenetration into one's mindh will arise as a body sensation and the brain stem should be attacked. Thus, we will Break ga new Electro sound Fieldh because a conventional Audio is not able to prepare such a circumstance.

    2. A New Sound Quality measure -An assessment system based on adjectives-

    Up to now, the electrically reproduced sound quality is usually evaluated by some specific electric characteristics such as a frequency bandwidth or a total of harmonic distortion. However, as well known, such measures scarcely reflect a true sound quality. Then the development of ghigh quality Audioh seems to be stopped.
    Our brand new idea is to use adjectives to evaluate gdeep admirationh because human express onefs admiration by adjectives. Subjective adjectives are not used but perceptible adjectives are used, because perceptible adjectives are objective, and the degree of sensitivity is a factor in the evaluation. Moreover if we use perceptible adjectives, other dependences on an individual evaluatorfs impression is not explicitly addressed.

    After long term researches, we have gotten important two principal components of whole adjective, in the case of the sound quality of high definition music.
    The deterioration of sound quality is principally by affecting subtle impressions such as gfloating atmosphere in the air-like resonanceh (n *) and gchest penetrating impressionh (n**). gFloating atmosphere in the air-like resonanceh and gchest penetrating impressionh are two of the principal components of an assessment system based on adjectives, used for an evaluation of high quality sound. (as to (n *) and (n**) see footnotes of TOP.)
    g The two key assessment phrases are recognized as representatives of the psychophysical adjectives usually used in experiments to find unknown physical factors and characteristics where a measuring instrument is a person who can understand and evaluate (n*) and (n**).

    3. How to develop an apparatus of true sound quality using the assessment system based on adjectives.

    Many preliminary assessment experiments to evaluate the sound quality show us that the following method is ideal;
    (1) find resources that contain the impression of (n*) and (n**).
    (2) prepare evaluators who can understand and evaluate (n*) and (n**).
    (3) experiments are as follows. For instance, in a case that new capacitor is changed in an amplifier or a CD player, the assessment test is accomplished using the ITU-R 7-grade comparison scale, where the reference sound is as reproduced using standard (unimproved) equipment.

    4. A new model of Perception of Deep Sense of Sound and the foundation of New Theory of Electro Sound Reproduction

    Our hypotheses are as follows. New model should be added to the conventional model of only the eardrum are;
    (1) Human feels not only the power of a sound but the wave front (which is the first transient of a tone signal) highly sensitive. This transient is directly transmitted to the basement membrane and to the brain. And arouse deep impression which will correspond to the fact that the consonant is very important to music as the Music conductor Sir Seiji Ozawa emphasize.
    (2) Human feels a deep sense brought by sound of music not only by the eardrum but also by the TANDEN : the center of body.

    5. Discoveries of new physical factors to implement the New Electro Sound Reproduction

    With aids of (n*) and (n**), We could discover the following factors.
    (1) Precise reproduction of signal wave form, especially the first transient of in electrical apparatuses, is necessary. And gthe faithful formation of a wave front of a signal wave formh is necessary at the speaker.
    (2) gHigh Q components, the characteristics of group-delay flat, multi channel method and reduction of digital distortionh are necessary. Consequently, the precise time delay adjustments between woofer, squawker, and tweeter are necessary.

    6. Conclusions

    Four representative adjectives discribed in TOP are ,tobe precise, assessemnt phrases which are "floating atmosphere in the air-like resonance" (n*) ,"chest penetrating impression" (n**) ,"the overwhelming presence" and "the groove" which means high spirits such as moving body.

    Aparatus are evaluated by above four assesments and remade.

    As a result, astonishing improvement of sound quality of deep impression is obtained. Performances of new sound system of Extra HI System M, of course, include performances of conventional sound apparatuses.
    We have accomplished a recording system to match to ga new Electro sound Fieldh also.
    During the course of development, we have been able to obtain, intimate relationship of mind each other beyond conversations.

    The recent disocovery is  great effects of scattered wave. Poles on a rear wall spread the sound field horizontally in a listening room (see the picture of TOP)

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    Footnotes:

    Recent discoveries on the New Electro Sound Reproduction
    (1) We have discovered that any CD player has an inborn matched CD weight, and the best sound is reproduced only when a CD weight match the inborn matched CD weight. Then, the adjustment adding a ring weight on CD disk is indispensable.
    (2) The jitter in a digital audio signal is a dominant factor causing deterioration in the sound quality on such high order sensations.
    If we complete improvements of (1jand i2j above, the sound quality is +2 (good) to +3 (very good) in the comparison 7 grade scale.