Postby rilynes » Sat Nov 11, 2017 5:12 pm
A few thoughts on CD's based on 28 years as a broadcast engineer and music show host. Cleaning the playing surface of a CD is rarely necessary, as opposed to cleaning the surface of an LP as a requirement ahead of playing to limit the amount of dust, etc. that would add to the snap, crackle and pop. If you do need to clean a CD, the proper method is opposite that of cleaning an LP: an LP is always cleaned with the grooves; a CD is cleaned by wiping out from the center to the edge as if you were cutting a piece of pie. That way, if you should happen to scratch the surface of the CD, it will be a minimal drop-out of data as it passes over the laser beam "reader". If you clean a CD by going around in circles (as you might clean an LP) you risk making a scratch that is long enough to create a drop-out to exceed the CD player's error correction circuitry. In any case, my experience has been that if CD's start mistracking after a period of time, it is often the laser in the player that needs cleaning. It is designed to focus a sharp point of light on the CD surface, and dust, etc. can diffuse the beam enough that it can't read the data on the CD surface accurately. And yes, there is a possibility in the CD manufacturing process that can make a CD "Marginal" in it's tracking. It might work in one CD player and not in another.
As to LP's vs. CD's? In my use of both media in my professional career, I can only say that the CD was manna from heaven. I could not find the source to cite, but memory recalls a lab test that determined more than half of an LP's high frequencies were gone after the fifth playing,and while not as dramatic a loss, every playing of an LP wore away more of the information in the grooves, even with the best playback styli and tone arms. CD's vs. MP3's? The MP3 is a step backwards in the amount of information available (think not-so-high resolution, more data crammed into a given bandwidth) from a top-quality CD. But my ears (and the ears of most reading this if I have deduced a median age accurately) won't know the difference. I dumped a collection in excess of 3,000 LP's, have built a new library of over 1000 CD's, but find that I listen mostly to BBC3 or view European orchestral concerts streamed free in HD via the internet - or to our local public radio station in the car.