Those applications genuinely make actual use of complex quantum physics. Quantum everything else is just baloney.There are many practical quantum effects and equipment nowadays. Really, a magnet lifting an object is quantum (relies on electron spin), as in classical dynamics a magnetic field can do no work. There's atomic clocks, quantum antennas, quantum gyroscopes, and more. Those are all real, tangible things that only work because of quantum engineering. But none of it really matters for audio.