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Difference between revisions of "Sound Quality Lite"
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More than 10 tones were detected in frame 1. | More than 10 tones were detected in frame 1. | ||
==FAQ about loundness == | |||
When we compute the loudness in Sound Quality Lite we get the above list of results in NVGate. | |||
Let’s find below the explanation of this loudness | |||
• ISO532-1 Specific loudness ch 1 | |||
According to the standards ISO532-1 : It is computed on the whole signal, it computed a loudness value in every 2 ms. | |||
• ISO532-1 : Loudness ch1 | |||
According to the standards ISO532-1 : the spectrum is computed on the whole signal. The standards is for stationary signal. | |||
• Psycho: SpecificLoudness ch1” and “Psycho:loudness ch 1 | |||
Not standardize loudness, but based on DIN 45631/A1-2010. (One value every 2 ms for profile, and compute on the whole signal for the spectrum) | |||
• Psycho IS0 532 B : | |||
According to IS0 532 B. It is computed on the whole signal, the standard is used for stationary signal, so there is only one value. | |||
• ISO532-2: Loudness Ch1: | |||
ISO532-2 standard : It is the “American Loudness standard” (This standard replaces ISO 532 A (loudness according to Stevens) and it is based on ANSI S3.4-2007 standard for calculating stationary loudness according to Moore. | |||
It is computed on the whole signal, the standard is used for stationary signal, so there is only one value. | |||
===Short history about loudness:=== | |||
There is 2 main ways to compute the loudness | |||
1) The “European” way : Zwicker method | |||
ISO 532-1 (release in 2017 ) this standards is a revision and based on ISO 532 B. | |||
It is based on DIN 45631/A1 standard for determining both stationary and time variable noise according to Zwicker. | |||
The new standards ISO 532-1 add: | |||
- avoid any uncertainty regarding the practical implementation. | |||
- Better continuity and comparability than earlier calculations. | |||
2) The “Amercian” Way. | |||
ISO 532-2 this standards is based and replaced ISO 532 A (loudness according to Stevens) | |||
The standard is based on the American ANSI S3.4-2007 standard for calculating stationary loudness according to Moore and Glasberg. | |||