The bit depth or number of bits per sample fixes the dynamic range. It is important to ensure that the transfer process takes advantage of the full dynamic range of the original recording. The procedure of normalising a low level archival file should be avoided, as this produces additional quantisation and granular noise in the digital domain.
HOW:
IASA recommends an encoding rate of at least 24 bit to capture all analogue materials. Set the bit depth at the A/D converter and make sure that the settings of the soundcard and the recording software fully correspond.
SEE:
IASA TC-04, p. 6.
Learning by Simulations: Analog/Digital Conversion
Mike Casey & Bruce Gordon: Sound Directions - Best Practices for Audio Preservation, pp. 11-13.
