>>12823122>To avoid all aliasing you require an infinite sample rateOnly if you also capture random high frequencies which are not part of your signal like that 84kHz you talked about
>digital low pass filterObviously meant before you make it digital
>an analog low pass filter can’t eliminate frequencies in your stop band only make them smallerYou can make them so small that they are comparable to the random noise you get anyway (so they will likely get ereased by it)
>any analog low pass filter will also distort your passband to some extentYes it will but if you get a good one, only near the cut off point (elsewhere the difference is tiny and almost constant so it's not a problem). You also can (and shoild) put the cut off point a bit after your max frequency to reduce the effect on your signal. Speakers themselves are low pass filters anyway and you may have noticed in shitty ones that they can't play high frequencies as loud as they can with low ones
Also Nyquist is literally what you need to have a perfect reconstruction, in practice they often use smapling frequencies many times higher than what Nyquist requires which also gives a lot of room for an analog low pass filter if you want it. In CD disks however I think they went almost at the bear minimum, with the max frequency being 22kHz. I think human hearing capability does not surpass 20kHz most of the time and the highest frequencies produced by musical organs being at around 22kHz but you can apply all of what I said with much higher sampling frequencies and the resulting signal will be the same as analog
