Reference level of standard tape?

[supertramp1979]

Hiya!
I was playing some of my billy joel 8-tracks the other day which are 70's.
I was playing some cassettes not too long ago which are from the 90's.
My question is, what are the operating levels of tape that go into consumer decks such as 8-tracks and cassette decks?

Have the reference levels changed over the years?

Thanks

 

[Tim Gillett]

Yes, mostly. The earlier operating levels were lower because the tapes werent as "high output".
Reel to reel tapes were generally higher than cassettes but the levels got higher with both with the later hotter tapes which also had lower noise.
But that doesnt necessarily tell you what level any given tape was recorded at.
The thing about tape recording is it was up to the company, the operator, to decide how heavily to modulate the recording. That's why there can be such a variation in output levels. Sure there was the limitations of the tape formulation but it was only an upper end limit, not a command.
The term operating level refers to a standard reference level for calibrating the tape machine and those levels varied a bit as I said. But even then staff could always ignore the strict guidelines and record far hotter than the meters indicated, or more conservatively. pushing the levels just gavce more distortion.
Tape reference levels could be pretty meaningless if machines werent maintained correctly and the staff making the high speed copies hadnt been trained well... which was probably often the case. It was a deadly dull, repetitive job after all.
Tim

 

[A Reel Person]

Have a look around here:...

http://www.teac.co.jp/testmedia/eng/products/tape_index.html
The only hard number I could find was:
Dolby Level MTT-150 3180µs & 120µs Dolby B/C/S Type Tone 200nWb/m

I have some official TEAC test tapes for Portastudios which are labelled with the reference fluxivity,... (but I'll have to check them later).

 

[A Reel Person]

Same here:...

http://www.almedio.co.jp/cassette.html