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Spurious Noises and Quality of HiRes

sweetsounds

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Apr 24, 2019
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I downloaded some Hi-Res recordings and in quite a number of cases there are issues in quality. (Maybe not audible, but then what's the point of HiRes anyway?)

Eric Clapton: Tears in Heaven from The Lady on the Balcony (MusicScope analysis)

- Noise floor at 90dB
- A roll off below 30Hz
- A constant noise at 30kHz and 45KHz (vertical bands in the image)
- strange side-bands
- a burst in the middle of the recording (horizontal band)


Tears in Heaven.PNG


Yet, sonically I found the recording somewhat smoother than the CD
1655546600071.png
 

Katji

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^^^Which explains why there is so much variation in process and QA.
 

sam_adams

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Dec 24, 2019
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All the noise in the 'hi-res' version is probably from the dithering they applied when they upsampled it from the CD version. The 30 kHz and 45 kHz noise band is probably from the device they used to do the processing.
 
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