Interesting how every generation views a product as “perfect” only for that opinion to change as time goes by. Early phonograph records were considered perfect and better than live music. Folks with long memories may recall when compact discs were first introduced in the early to mid 1980s, they were advertised as “perfect sound forever”. For many years, each CD had some boilerplate text at the back claiming that CDs were best sound one could obtain etc. Now of course everyone thinks Roon streaming or some variants are perfect.
I’m holding out hope for a better recording technology in the decade to come. To me PCM is fundamentally flawed and no amount of skullduggery with transports or DACs will fix the inherent flaws of PCM technology. Unlike analog, in PCM, distortion greatly rises as the volume reduces, so that quiet passages — say a single oboe playing in an orchestra — are rendered with very poor fidelity. Unlike analog noise, which is largely uncorrelated with with signal, digital PCM noise is correlated with signal intensity.
Human hearing is inherently nonlinear and highly adaptive to signal level. A much better technology than PCM would adaptively allocate bits to where human hearing is acutely sensitive — the midrange and in particular quiet to normal volumes — and not waste it in regions where we are mostly deaf or in having dynamic range beyond what any listening room can possibly support (e.g., above 20 kHz and below 30 Hz, and dynamic range above 80-90 dB).
There have been a lot of theoretical advances in signal processing since the age old Nyquist theorem that underlies PCM technology (i.e., Nyquist theorem mandates sampling at least twice the rate of the highest frequency, so CD technology used 44.1 kHz as the original baseline). Some of these advances like compressed sensing have transformed other areas, but not yet been applied to music, which continues to be based on largely obsolete math. But that will change in the coming decades, and PCM will become a quaint historical artifact.
The real revolution will occur when quantum computing takes over and we can reliably transport qubits using quantum entanglement (which won this year’s Nobel prize in physics). That will make today’s internet look like chiseling on a stone tablet, like the Babylonians did 5000 years ago. Qubit encoded music should be able to provide far higher fidelity than any PCM encoding can achieve.
The Nobel Prize in Physics 2022 was awarded jointly to Alain Aspect, John F. Clauser and Anton Zeilinger "for experiments with entangled photons, establishing the violation of Bell inequalities and pioneering quantum information science"
www.nobelprize.org
Fascinating field however!
