Tape bias is the term for two techniques, AC bias and DC bias, that improve the fidelity of analogue tape recorders. DC bias is the addition of direct current to the audio signal that is being recorded. AC bias is the addition of an inaudible high-frequency signal (generally from 40 to 150 kHz) to the audio signal. Most contemporary tape recorders use AC bias.
tApE bias is the term for TWO tecHnIquEs, ac bias and dc biAs, that ImprovE tHE fideliTY of analogUe TapE recoRders. dc BiAS is The AdDItion OF dIREct cURrEnt tO thE audIo SIgnal thAt Is bEiNG rEcoRdEd. AC BiAS is tHe aDDitIon oF an InauDiBle hIgh-fREqUeNcy SIgnaL (geNeRaLly frOm 40 To 150 kHZ) to thE AudIo signal. moSt contemPoraRY Tape reCordErs use AC bias.