Cassette Tapes..Dolby B or C?


I still have a tape deck in my system, and have a few tapes that are nice for quiet background music. The tape deck has a switch to select Dolby B or Dolby C (or none). There seems to be no marking on prerecorded tapes to indicate the type of Dolby processing. On a tape I was just playing B sounds about right. Should I assume that all prerecorded tapes are B unless otherwise stated?
eldartford
Eldartford

Further to that point, I always found it curious - as an audiophile - to think that in the late '70s to early 80's, tape decks could make great recordings that were virtually indistinguishable to the original. (At least for laymans', if not golden ears.)

But it was "digital", which didnt even sound as good, that drove paranoia and copy protection to new, ridiculous heights.

I guess the Napster police have never heard of Nakamichi?
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All this talk about, TDK, Nakamichi, Dolby has brought back fond memories, I think I am going to service my Nakamichi this weekend :-)
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Tvad

It rounds the CDs and softens the high frequency fatigue?

And throws in the tiniest amount of tape hiss - enough to get sentimetal about analogue?