how is digital sound created?


So sound is a vibration which is created from things rubbing or banging together etc. If stuff isn't interacting with something to create a sound how are sounds created from nothing? I.e in the digital world? Music on an iPod or a beep from a computer? I have always wondered what the noise's are and that come from computers when they are 'thinking' or working - wtf's going on there?

lucaspeni
yage
There’s no interpolation happening when performing error correction since there’s no ’guessing’
You are mistaken. Interpolation is "guessing" by definition (in this context) and interpolation is part of the CD standard.
The proper bits are either recovered or the data stream is so corrupted that some errors remain. In the latter case, the player may mute the output or cease playback.
That’s how a data disc works because it has to be bit perfect. But it’s not how digital audio works at all. The Reed-Solomon error correction code is part of the CD standard and, as MC noted, it’s all part of the fun math that makes digital audio:
" ... whereas subsequent constructions interpret the message as the values of the polynomial at the first k points a 1 , … , a k {displaystyle a_{1},dots ,a_{k}} and obtain the polynomial p by interpolating these values with a polynomial of degree less than k ..."
+1 cleeds! Too many still believe that more expensive DACs do a better job of "smoothing out" the steps between digital samples. Nonsense! My $99 DAC outputs rival those of any four-figure DAC (low noise, low distortion, accurate LSB ...).
You are mistaken. Interpolation is "guessing" by definition (in this context) and interpolation is part of the CD standard.
@yage was talking about 'error correction' and indeed that is done without guessing. There is a stage beyond error correction where the data's too corrupted to do error correction and that's normally termed 'error concealment'. Its at that point where interpolation - which indeed is a kind of guessing in this context - is used. Muting is the final stage where the data's too far gone even for interpolation/concealment.
@abraxalito

Thanks for that clarification - good to know. It's a linear interpolation, so very different from the interpolating filters used in the DACs themselves. The reference I found is at this link - https://www.pearl-hifi.com/06_Lit_Archive/02_PEARL_Arch/Vol_16/Sec_53/Philips_Tech_Review/PTechRevie...

Of course, all this only applies to compact disc digital audio. In case anyone is interested, I found an overview of the error correction approaches in other disc formats - https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.462.3524&rep=rep1&type=pdf