Best way to clean my old CD’s

I've tried various cleaning methods for CD-SACDs; I don't recommend any cleaning product. The two best methods (even sonic) are : 1 - demineralized water and a smooth microfiber cloth like those used for camera lenses; 2 - If the disc has any dirty, use a solution of IPA and demineralized water (70% + 30%) and a smooth microfiber cloth. Always clean in a radial direction and soak up any remaining drops with a soft, non-rough paper towel, without rubbing.

@mahler123 

I also find it interesting that some individuals advocate don’t do anything to a CD unless it’s really in bad shape then advocate using an unnecessarily aggressive and potentially deleterious cleaning method

I advocate doing nothing unless there are audible problems.  I cannot think of anything less aggressive than a no-contact ultrasonic cleaner.  For CDs, I get away with warm water and one drop of liquid detergent which gets rinsed off before drying.

For records, I use de-ionised water, polysorbate 'detergent' and Ilfoton added to the rinse water.  But CDs are flat polycarbonate.

Unlike records, CDs are incredibly tolerant of scratches.  The laser beam is a wide cone, focused on the label side of the disk.  It averages over a big circle on the clear side.  Then error detection and recovery take over.  Remember the demonstration disk playing without audible issues despite a 1/8" hole drilled through the playing area?

@richardbrand 

There is a world of difference between cleaning LPs and cleaning polycarbonate discs.  Many LPs from back in the day were ill treated, then stored in non climate controlled environments for years, and it absolutely makes sense to have to use sophisticated cleaning techniques to try and maximize their performance.

  CDs, otoh, are easy peasy.  They will rarely need it-as you say do it only if it won’t play-and a simple solvents and a good cloth with do it

I appreciate being reminded that they are polycarbonate. Thinking back on items I’ve encountered that were , motorcycle windshields, helmet visors and the interior windows of the high security building I worked in. I forget that they are essentially Lexan and that’s some tuff stuff. We had windows that were two layers of glass with a layer of Lexan sandwiched in the middle and overall about an inch thick. When these windows were defeated and needed replacement immediately, maintenance used 1” thick Lexan until an appropriate window could be manufactured. Definitely off topic but what the heck. Fortunately I acquired a few CD’s of artists I can’t stand so I can experiment with them. 😆 Have a Great Day , Mike B. 

Windex and Kleenex.