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by iforgotpassword 1292 days ago
Yep. Every tiny dust particle makes an audible pop, while an actual stylus would've just pushed it out of the groove.
2 comments

So laser turntable needs a leading 'dust plow' ?
That sounds good! Two other solutions:

- low pass filter. Assuming the dust is small compared to the expected movement in the groove, you can filter it out electornically.

- dust detector. Nikon had a cool 35mm scanner... instead of RGB, it had an additional IR layer at an angle just to detect dust. So, automated dust removal tools knew if a black spot in an image was supposed to be there, or if it was actually dust. Here, extra optics would know if the laser was reading dust and could mute/filter the sound during that time.

Interesting ideas!

The 'dust detector' is 'Digtal ICE' that you'll sometimes see labeled on scanners. (https://en.wikipedia.org/wiki/Digital_ICE)

Someone should try doing a dsp+ml hybrid filter that takes both the optical signal and the generated audio into account to filter out the crackling