A high orientation effect of cobalt-adsorbed gamma and chromium-dioxide particles for audio recording

Co-adsorbed gamma and chromium-dioxide particles were coated at magnetic fields of O, 1.0KOe, 2.5KOe to investigate magnetic and audio recording properties. We have achieved very high Rs of 91.5% and Br of 1830 gauss for Co-adsorbed gamma, and Rs of 86.3% and Br of 1700 gauss for chromium-dioxide particles coated at 2.5KOe. The increase of MOL(315Hz) was 4.4dB for Co-adsorbed gamma and 3.7dB for chromium-dioxide tape corresponding with the increase of tape Br. But the increase of bias noise level(A-weighted) was only O.6dB and O.7dB respectively.