Casete audio sigilate METAL TYPE IV:
_TDK MA 110, an 1988, made in Japan, Super wide dynamic range, Ultra-fine Finavinx metal formulation, pret 239 lei/buc.;
_PDMagnetics (Philips DuPont Magnetics), an 1981, made in Holland, Ultra Coercivity, pret 99 lei/buc.
_maxell MX46, made in Japan, Super Silent Phase Accuracy, Super Stabilized Pure Metal, pret 199 lei/buc;
_TDK MA-XG 60, an 1990, made in Japan, Dual-layer of Finavinx ultra-fine metal particles, Wider dynamic range for critical master recordings, pret 425 lei.

Coercitivitatea benzilor audio variază de la 350 Oe la 1200 Oe. Particulele cu coercibilitate inalta sunt mai dificil de sters, de polarizat si de înregistrat, dar si mai putin predispuse la pierderi de frecventa inalta in timpul inregistrarii si la interferente externe si autodemagnetizare in timpul stocarii. Philips DuPont Magnetics (PDMagnetics) a produs si pentru marantz: caseta audio marantz MM4 Type IV Metal, caseta audio MC2 Type II. DuPont a fost inventatorul casetei audio crom TYPE II.

*alte informatii la mesageria olx.