Funny how some analog zealots have not so much trouble listening to digital files run back thru lossy homogenizer tape decks… to wit Famous Blue Raincoat.
https://youtu.be/0AHBw7wItpI?t=24
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?
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millercarbon ... Really good expensive DACs have a lot more quality parts and do a lot more processing trying to smooth the signal out by interpolating values in between the stair steps ...That is completely mistaken but a common misnomer. The only interpolation that is part of the digital audio standard is when it is used for error correction. Because the data on a CD is encoded redundantly and interleaved (and cached in streaming) error correction is actually quite rare. Within the bandwidth of the system, the Fourier theorem shows us that digital audio can perfectly describe the analog waveform. If you have doubts, watch this. (Kindly note that I'm not claiming digital audio is "Perfect Sound Forever." But if we want the best sound from digital, it's helpful to understand how it works.) It's odd how many audiophiles refuse to accept this math, which is conceptually simple even if the details are not. Consider that the Fourier mechanism also explains perfectly how the squiggles on an LP can represent a full orchestra. |
The only interpolation that is part of the digital audio standard is when it is used for error correction. There’s no interpolation happening when performing error correction since there’s no ’guessing’. 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. Interpolation is required whenever you increase the sampling rate in digital audio. Most DACs these days, whether some form of multibit resistor ladder or the sigma delta variety, increase the sampling rate to net several benefits such as reducing or ’shaping’ quantization noise or relaxing the design requirements for the analog reconstruction filter. Here is a great tutorial on oversampling / upsampling and interpolation from Analog Devices: https://www.analog.com/media/ru/training-seminars/tutorials/MT-017.pdf dspGuru also has some great information on interpolation: https://dspguru.com/dsp/faqs/multirate/interpolation/ |
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