Japanese Zep CD's-the sound remains the same

I have no difficulty believing that manufacturing differences exist, nor that these differences affect the lifespan of CDs (though I've yet to have a single CD go bad on me in 20+ years). I also can see that they might affect sound quality in a poorly designed CD player (with marginal tracking, error correction, and jitter suppression).

What I would like an explanation of is how this effects the sound. Has anyone shown that errors make it past the error correction coding ? Has anyone done double blind proofs of difference with a reclocking DAC ?

i've been involved in the production end of audio and video for two decades and know the faciility standards from one manufacturer to another are not the same..... and it does have a direct impact on the sound and picure of discs even on the same title....as well as the shelf life....google and research......in many ways there are similarities to the glory days of vinyl.

one more thing and i'm out....there are numerous manufacturing and stability studies that have been done on optical discs new and old. most of the time you do get what you pay for with software....even of the prerecorded music variety. there are things hi end hardware can't cure alone. enjoy zepplin no matter matter the country of origin

Seandtaylor99,
I have had about 150 CDs go bad on me. All manufactured by Philips Dupont Optical (PDO) in the UK. Fortunately all but 2 have been replaced with the same titles. The majority were Hyperion classical CDs. Most recent have been Deutsch Gramophone (Archiv). I now inspect them every six months.

I'm sorry Jay Douglas there may be truth in what you are saying in general terms however I can assure you these discs are identical (Physical Graffiti)and THAT is the point of the post.
These Japanese imports are not cheap and when members on this forum suggest that there is sonic benefits to be had then they really need to stand by their statements.