Do you want us to list the worst masters we've ever heard? If so, I can think of a few
Whoah! That sucks.Cold Spring Harbor - Billy Joel
The album was released by Family Productions, but through an error in the album's mastering, the songs played slightly too fast, causing Joel's voice to sound unnaturally high (a semitone higher).
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SH
Years ago I had the original Elektra CD of Love's classic album "Forever Changes". I was always bothered by the high pitched tone that pervades most of the album but assumed it must be on the master and put up with it.
Then, along came the 2001 Rhino remaster and finally I realised that the tone was not on the master and promptly sold the original in favour of the remaster...Forum member Zal Schreiber, the Atlantic Studios mastering engineer credited with the mastering of the original Elektra CD clarified the details behind the dreaded high pitched tone on the original release. From what I understand, Zal did indeed prepare a master for the original CD release but before it was pressed Bruce Botnick and Paul Rothschild decided they wanted to master it and Zal's master was pulled. It is the replacement overseen by Botnick and Rothschild that has the tone - apparently the result of an engineering snafu whereby someone left a 12kHz test tone running through the desk during at least one of the mastering sessions (it is not present on all tracks).
^^^^c'est ça^^^^Well, it's almost impossible to tell how good or bad a master is without hearing the pre-master.