Les 0.38db peuvent peut-être (surement ?) provenir du dithering appliqué pendant la conversion.
Cela ne change pas globalement la dynamique (généralement inférieure à la limite déjà trés élevée du CD).
Cordialement
FDRT
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Modérateurs: Modération Forum Haute-Fidélité, Le Bureau de l’Association HCFR • Utilisateurs parcourant ce forum: Davsevelyninmel, frmiket et 52 invités
Les Lecteurs CD & SACD
normalement le dithering ne s entend pas ... Dc on ne devrait pas percevoir cette difference de niveau, si elle est expliquee par le dithering ?
La configuration dans mon profil
Hi-fi : nas Qnap TS221, Transporter, Minidsp SHD, Soncoz SGD1, BoXem 4215/E2, Vivid Audio B1, Rel G2
HC : Pana EZ950, Vivid, Scandyna Minipod & Cinepod, Pana UBD820, Yamaha Rxa 1040
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JG Naum - Modérateur Œuvres & Multimédia
- Messages: 7575
- Inscription Forum: 12 Mar 2005 20:08
- Localisation: Paris
A lire absolument je pense :
http://jn.physiology.org/content/83/6/3 ... l.pdf+html
Abstract :
Although it is generally accepted that humans cannot perceive sounds in the frequency range above 20 kHz, the question of whether the existence of such “inaudible” high-frequency components may affect the acoustic perception of audible sounds remains unanswered. In this study, we used noninvasive physiological measurements of brain responses to provide evidence that sounds containing high-frequency components (HFCs) above the audible range significantly affect the brain activity of listeners. We used the gamelan music of Bali, which is extremely rich in HFCs with a nonstationary structure, as a natural sound source, dividing it into two components: an audible low-frequency component (LFC) below 22 kHz and an HFC above 22 kHz. Brain electrical activity and regional cerebral blood flow (rCBF) were measured as markers of neuronal activity while subjects were exposed to sounds with various combinations of LFCs and HFCs. None of the subjects recognized the HFC as sound when it was presented alone. Nevertheless, the power spectra of the alpha frequency range of the spontaneous electroencephalogram (alpha-EEG) recorded from the occipital region increased with statistical significance when the subjects were exposed to sound containing both an HFC and an LFC, compared with an otherwise identical sound from which the HFC was removed (i.e., LFC alone). In contrast, compared with the baseline, no enhancement of alpha-EEG was evident when either an HFC or an LFC was presented separately. Positron emission tomography measurements revealed that, when an HFC and an LFC were presented together, the rCBF in the brain stem and the left thalamus increased significantly compared with a sound lacking the HFC above 22 kHz but that was otherwise identical. Simultaneous EEG measurements showed that the power of occipital alpha-EEGs correlated significantly with the rCBF in the left thalamus. Psychological evaluation indicated that the subjects felt the sound containing an HFC to be more pleasant than the same sound lacking an HFC. These results suggest the existence of a previously unrecognized response to complex sound containing particular types of high frequencies above the audible range. We term this phenomenon the “hypersonic effect.
J'ai ouvert un topic là-dessus.
Amicalement,
david
EDIT :
Voici le vademecum des études publiées, depuis 2000 à 2009 :
http://www.yamashirogumi.gr.jp/akira-e/ ... nce_e.html
http://jn.physiology.org/content/83/6/3 ... l.pdf+html
Abstract :
Although it is generally accepted that humans cannot perceive sounds in the frequency range above 20 kHz, the question of whether the existence of such “inaudible” high-frequency components may affect the acoustic perception of audible sounds remains unanswered. In this study, we used noninvasive physiological measurements of brain responses to provide evidence that sounds containing high-frequency components (HFCs) above the audible range significantly affect the brain activity of listeners. We used the gamelan music of Bali, which is extremely rich in HFCs with a nonstationary structure, as a natural sound source, dividing it into two components: an audible low-frequency component (LFC) below 22 kHz and an HFC above 22 kHz. Brain electrical activity and regional cerebral blood flow (rCBF) were measured as markers of neuronal activity while subjects were exposed to sounds with various combinations of LFCs and HFCs. None of the subjects recognized the HFC as sound when it was presented alone. Nevertheless, the power spectra of the alpha frequency range of the spontaneous electroencephalogram (alpha-EEG) recorded from the occipital region increased with statistical significance when the subjects were exposed to sound containing both an HFC and an LFC, compared with an otherwise identical sound from which the HFC was removed (i.e., LFC alone). In contrast, compared with the baseline, no enhancement of alpha-EEG was evident when either an HFC or an LFC was presented separately. Positron emission tomography measurements revealed that, when an HFC and an LFC were presented together, the rCBF in the brain stem and the left thalamus increased significantly compared with a sound lacking the HFC above 22 kHz but that was otherwise identical. Simultaneous EEG measurements showed that the power of occipital alpha-EEGs correlated significantly with the rCBF in the left thalamus. Psychological evaluation indicated that the subjects felt the sound containing an HFC to be more pleasant than the same sound lacking an HFC. These results suggest the existence of a previously unrecognized response to complex sound containing particular types of high frequencies above the audible range. We term this phenomenon the “hypersonic effect.
J'ai ouvert un topic là-dessus.
Amicalement,
david
EDIT :
Voici le vademecum des études publiées, depuis 2000 à 2009 :
http://www.yamashirogumi.gr.jp/akira-e/ ... nce_e.html
- DaveStarWalker
- Messages: 8844
- Inscription Forum: 25 Aoû 2006 11:08
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Peux-tu indiquer le lien renvoyant à ton sujet stp ?
- tututpouet
- Messages: 4710
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- Localisation: Paris
lol les mecs en arrivent à l'EEG pour justifier le format bel effort ..
- Ygg
- Messages: 1992
- Inscription Forum: 28 Mar 2006 21:47
- Localisation: Dreiländereck baby !
Dommage ! Il est déjà mort. ...
Bon, pour ma part, ce n'est le thalamus gauche qui augmente significativement quand on tente de m'exciter le Cortex !
Bon, pour ma part, ce n'est le thalamus gauche qui augmente significativement quand on tente de m'exciter le Cortex !
- FDRT
- Messages: 6575
- Inscription Forum: 23 Jan 2004 19:48
tututpouet a écrit:Peux-tu indiquer le lien renvoyant à ton sujet stp ?
Hop :
viewtopic.php?f=13&t=29965509
J'ai vérifié, les liens sont fonctionnels.
Amicalement,
David
- DaveStarWalker
- Messages: 8844
- Inscription Forum: 25 Aoû 2006 11:08
- Localisation: Système solaire (pour l'instant)
Je déterre ce thread pour voir ou entendre si notre très sympathique Haskill qui depuis le temps a dû installer ses nouvelles prothèses auditives nous tienne informé en 2016 "quel intérêt du 24/96 en Hi-fi ?" par exemple avec Audivarna.
Alain, si tu m'entends encore ? A défaut, peut-être que tu vois ce que j'écris. Bises.
Alain, si tu m'entends encore ? A défaut, peut-être que tu vois ce que j'écris. Bises.
- Winchestermann
- Messages: 13100
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- Localisation: Juste derrière Brigitte Lahaie
- Ygg
- Messages: 1992
- Inscription Forum: 28 Mar 2006 21:47
- Localisation: Dreiländereck baby !
Merci...donc à part changer mes oreilles pour celles de mon chien, rien à faire.
- Winchestermann
- Messages: 13100
- Inscription Forum: 27 Mar 2002 2:00
- Localisation: Juste derrière Brigitte Lahaie
c'est l'idée, en gros
- Ygg
- Messages: 1992
- Inscription Forum: 28 Mar 2006 21:47
- Localisation: Dreiländereck baby !
Ygg a écrit:lol les mecs en arrivent à l'EEG pour justifier le format bel effort ..
Et encore... l'EEG enregistré à un autre moment que pendant l'écoute et en disant "il doit y avoir un décalage".
- Pio2001
- Contributeur HCFR 2019
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Ygg a écrit:http://people.xiph.org/~xiphmont/demo/neil-young.html
WOUHHAAAAAAAA !!!!!!! Extraordinaire cet article. Avant de se lancer dans la dématérialisation il devrait être obligatoire de lire ça.
Je redonne le lien traduit : http://translate.google.com/translate?u=http%3A%2F%2Fpeople.xiph.org%2F~xiphmont%2Fdemo%2Fneil-young.html&hl=fr&langpair=auto|fr&tbb=1&ie=utf-8
Ma signature prend tout son sens...
- metoujpense
- Messages: 1322
- Inscription Forum: 29 Mar 2001 2:00
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