Tape Flux Measurement Revisited

McKnight JG, Cortez BE, McKnight JA. Tape Flux Measurement Revisited. J Audio Eng Soc. 1998;46(10):845-858. Available from: https://aes.org/publications/elibrary-page/?id=10269

@article{McKnight1998_10269,
  author = {McKnight, John G. and Cortez, Benito E. and McKnight, Jeffrey A.},
  title = {{Tape Flux Measurement Revisited}},
  journal = {Journal of the Audio Engineering Society},
  volume = {46},
  number = {10},
  pages = {845--858},
  year = {1998},
  month = oct,
  publisher = {Audio Engineering Society},
  url = {https://aes.org/publications/elibrary-page/?id=10269}
}

TY  - JOUR
TI  - Tape Flux Measurement Revisited
AU  - McKnight, John G.
AU  - Cortez, Benito E.
AU  - McKnight, Jeffrey A.
T2  - Journal of the Audio Engineering Society
J2  - J. Audio Eng. Soc.
VL  - 46
IS  - 10
SP  - 845
EP  - 858
PY  - 1998
DA  - 1998/10/06
UR  - https://aes.org/publications/elibrary-page/?id=10269
PB  - Audio Engineering Society
LA  - en
AB  - Analog magnetic recording standards specify the recorded signal magnitude in terms of short-circuit flux per unit track width, called fluxivity. Two flux measurement methods are standardized: a direct ac method using a high-efficiency head (AES7/ANSI S4.6) and a transfer-to-dc method using a fluxmeter (German standard DIN 45 520). A transfer-to-dc measurement made in the 1950s is used to calibrate the fluxivity of German calibration tapes. When these tapes are measured by the direct ac method, the fluxivity is 10% less than the stated value. Thus the 1950s German transfer-to-dc measurement was 10% more sensitive than the direct ac measurement. A new comparison of the two measurement methods shows that they actually have the same sensitivity; the experimental error of our measurements is about ±1%. Thus we conclude that the German measurement in the 1950s must have had a 10% error, and that the fluxivity on all of the calibration tapes based on the old German measurement is 10% less than the stated value'tapes identified as 320 nWb/m are actually 288 nWb/m.
ER  -