![]() ![]() Yes, there have been attempts to replace the CD with something better – in the early 1990s not one but two ‘high-resolution’ audio formats appeared, and battle was joined between DVD-Audio and the Sony/Philips Super Audio CD (or SACD), the former offering 24-bit audio quality for greater resolution, improved dynamics and greatly reduced distortion, while the latter’s Direct Stream Digital system used a sampling rate of 2.8224Mhz, 64x that of CD and single-bit sampling. However, 16-bit/44.1kHz is what we got back in 1982, and 16-bit/44.1kHz is what CD still uses more than three decades on: we’ve been trapped in a technology ‘almost good enough’ 30 years ago for all that time, just like we would be with everything else we own if all development had been stopped back then. Ideally, at least 20-bit resolution at 60 kHz sampling frequency would have been better.’ Indeed, some say it was only ever almost good enough for high-quality sound reproduction: Malcolm Hawksford, Professor of Psychoacoustics at Essex University, feels that, ‘It was near the limit, but in my view probably a bit marginal. CD is a 16-bit, 44.1kHz system, what’s needed to improve conformity between the analogue original and the digitised version is a combination of more bits in each samples, and more samples for each second of music: the more bits you use, the more natural the music sounds, and the faster the samples, the wider the frequency range.ĬD’s 16-bit/44.1kHz digital system may have been the apparent state of the art in 1982, but it didn’t take long for it to get past its sell-by date. With PCM, the two basic factors that determine the sound quality are bit depth (which determines the quality with which the analogue signal is digitised), and the sampling frequency (which is the number of times per second that the analogue signal is digitised). ![]() 30 years on, we can do so much better.ĭigital audio encodes the analogue musical waveform, using Pulse Code Modulation. CD running orders could be programmed, favourite tracks repeated and the duff ones skipped, and in time added features such as CD Text readouts of album, track title and artist would become possible.įor all that, CD was always a compromise, using technology that was only just cutting edge at the time. CD was revolutionary when it first appeared, just over 30 years ago: none of the surface noise of well-played LPs, no annoying ticks and pops caused by invisible scratches, no need to handle the discs with kid gloves – though the early demonstrations of discs smeared with jam still playing were a little over the top! – and instant access to any track on an album at the push of a button. ![]()
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