Sound Quality Notes
### DRAFT PAGE - WORK IN PROGRESS ###
| Term | Definition |
|---|---|
| Break up | Audio signal is only intermitently audible, usually with distortion. Typically caused by damage to the original carrier, a problem with the original recording device or the signal transmission (radio) |
| Cross-talk | Tape / cassette transfer. Signal recorded on one channel of a multichannel (half-track, quarter-track) tape is audible in the adjacent channel(s) during playback. For example a half-track tape, with two seperate recordings running in opposite directions, the audio in the Right channel is audible (in reverse) in the Left channel during replay. This is typically a result of the guard-band (the channel seperator) of the tape recording machine’s record head being a narrower width than the replay machine’s, causing the audio to ‘leak’ between channels |
| Drop out | Audio signal disappears for a period of time |
| Hiss | High pitched noise. Can be inherent surface noise of the carrier, a result of physical damage or a defect with the orignal recorder |
| Locked groove | Disc transfer. Stylus is stuck in a groove and traces the same section of audio over an over again. Typically caused by surface damage that ‘locks’ the stylus in the same groove revolution. However, some discs are intentionally cut with locked grooves for technical or artist purposes |
| Low level | Recorded signal is very quiet |
| Medium wave / long wave broadcast | Low quality AM radio transmission. Recordings typically exhibit broadcast inteference in the form of noise and distortion |
| Print-through | Tape / cassette transfer. An audible ‘echo’ caused by the transfer of magnetic energy between layers of wound tape. Depending on how the tape is stored the echo can be heard before the prominent signal (pre-echo) or after (post-echo) |
| Pops / clicks | Disc transfer. Sharp transient sounds caused by surface damage to the disc |
| Poor tracking | Disc transfer. Stylus is not able to track the disc’s groove accurately resulting in distortion, signal drop-out and groove skipping |
| Off-air broadcast | Content is recorded directly from broadcast radio by either connecting the output of the radio to the recording device or placing a microphone in front of the speaker. Recordings typically exhibit broadcast inteference in the form of noise and distortion |
| Pre-echo / post-echo | See Print-through |
| Radio Frequency Interference (RFI) | Noise, distortion or other sound interefence picked up during radio transmission |
| Surface noise | Noise inherent to all analogue formats e.g. ‘tape hiss’ |
| Wow and flutter | Tape / cassette transfer. Variable replay speed resulting in slow (wow) and fast (flutter) changes in pitch. Typically caused by a defect with the orignal recording device or carrier degradation |