Skip to main content

Posts

Is Hi-Res music worth what it offers? (2/2)

Disclaimer: My purpose here is not to denigrate a particular recording, release or label but to focus your attention on the technical problems of recordings for which the benefit of Hi-Res is not guaranteed. Cathode Ray Tube forever. With the introduction of TV in the 80s and 90s in recording studios the Cathode Ray Tube (CRT) was living its mark in the recordings. A 15 kHz interference ton corresponding to the scanning frequency of the tube is indelibly recorded in audio masters (this happens when a TV screen was near the microphone when the music was recorded). At that time few people could detect them and they remained undetected until in the 2000s spectrum analyzers became more common and became more accurate. Many recordings have a frequency spike at exactly 15625Hz (15750Hz NTSC standard in the USA), such as Nick Cave's very good 1996 album Murder Ballads. 15.6 kHz spike on Nick Cave - Murder Ballads 16-44. This problem appears on some vinyl albums. It is commonly observed o
Recent posts

Is Hi-Res music worth what it offers? (1/2)

Digital recordings exist in two main encoding formats. The PCM (Pulse Code Modulation) format which encodes the signal from n-bit samples (e.g. 16 bits for CD) taken at regular intervals (number of samples per second, e.g. 44100 times per second for CD) and the DSD (Direct Stream Digital) format which encodes the signal on a single bit but at very high speed ( Delta-Sigma modulation ). Recordings using the PCM are available in several resolutions defined by the number of quantization bits and the sampling rate: 16 bits, 44.1 kHz (Audio CD quality) 16-bit, 48 kHz (DVD standard PCM) 24-bit, 48 kHz (DVD Extended PCM) 24 bits, 44.1 kHz 24 bits, 88 kHz 24 bits, 96 kHz 24 bits, 176 kHz 24 bits, 192 kHz 24 bits, 352 kHz There are other resolutions including 32-bit floating but not available on the market. Obviously the higher the resolution used, the better the sound should be with a gain in the high frequencies and in the signal to noise ratio (in theory 98 dB in 16 bits, 144 dB in 24 bits)

The Audio Compact Disc, how does it work?

The Compact Disc Digital Audio (CD-DA) was developed by Philips and Sony in the 1970s and introduced on the market in 1982. The specifications of the CD-DA, the "Red Book" (IEC 908), are sold by Philips, but a simplified version can be found under the reference ECMA-130, which can be downloaded in PDF format from www.ecma.ch .   The Audio CD contains a maximum of 99 tracks. Each track lasts at least 4 seconds. The tracks are chained together (in the case of concerts) or can be separated with a pause. Each track can be divided into 99 indexes. Usually a track has two indexes, one for the pause and one for the music. The indexes have not really found their place, they could have been used to find highlights in a piece of music.