Primer on Digital Audio Recording

The process of digitizing audio data is a very important step in obtaining a distortion-free recording. It is usually easier to avoid distortions during digitizing than to try to eliminate them after a recording has been made. Such distortions include microphone hiss, power-line noise, drive motor hum, etc.

The following basic rules allow you to perform digitizing of audio data with the maximum possible quality:

  • For recording audio to PC, use high-quality and accurate audio equipment, such as the sound source (tape, turntable, microphone), sound card, connection cords, etc.
  • Clean the tone arm of your LP player or tape heads (for exact information on this, refer to the documentation provided with your equipment). If possible, clean dust and dirt from the magnetic tape or LP itself.
  • Do not connect the headphone output to the Line-in of your sound card. For quality digitization of sound, you need to use audio equipment that has a line-out. Otherwise, the resulting quality may not be adequate. Additionally, there is a risk that such a setup will damage your sound card.
  • Normally, a turntable cannot be connected directly to a PC’s sound card (refer to the documentation provided with your equipment for specific information). Most LP players have to first be connected to a pre-amp that has a special “Phono” input. Then the pre-amp output is connected to the input line of your sound card.
  • Try to remove all electrical equipment that is not used for recording and that could potentially cause electromagnetic noise (electric cords, fans and other household equipment, cell phones and other communications equipment, etc.).
  • If you are recording sound from a microphone, ensure that there is silence in the room.
  • When recording music, always use either an uncompressed format that, at minimum, corresponds with standard CD quality (44100 samples per second, 16 bits per sample, stereo) or compressed format for quality recording (MP3, Ogg Vorbis, WMA, FLAC - with the same sample rate and a bit rate of no less than 128 kbps). For the recording of speech, you can use a lower sample rate (down to 8 kHz), however it is not recommended.
  • Correctly adjust the recording level on your PC. A recording level that is too high can result in a distortion (clipping), which is audible as a crackle and is difficult to remove. A recording level that is too low leads to a lower sound/noise ratio (SNR) and increases the background noise on a recording.