Camcorder Sounds: Understanding What Your Audio Goes Through (page 4)
And So...
Understanding the different audio recording methods will assist you in deciding which is best for you. You might need more than just the single linear track of VHS. If you want to edit the sound of your videos, the three tracks of the VHS hi-fi/linear combination may be just the thing. Maybe 8mm's AFM tracks will meet your needs if you don't plan to use time code. Or perhaps you can afford to go all the way and use Hi8 with PCM audio for full audio editing capability.
Whatever route you choose, you'll have a better appreciation of your audio when you understand what it goes through.
Glossary of Audio Terms
- AFM
Audio Frequency Modulation. A noise-resistant method of encoding and recording audio information. - AGC
Automatic Gain Control. A circuit that adjusts the signal strength of incoming audio signals to optimize recording. - Ambient Sound
Any natural sound (wind, cars, voices, etc.) at the location of your shoot. - Hertz or Hz
A unit for measuring frequency. 1 Hertz=1 cycle per second. - Hi-fi
A stereo FM recording standard used in VHS-family VCRs and camcorders. - LED
Light emitting diode. Often used for metering audio signal strength. - Limiter
A circuit which keeps signal levels below a certain point to avoid distortion. - Multiplexing
The mixing of different signals into a single signal, to be separated later. - Noise
Any unwanted elements introduced into an audio signal. They can be electrical or ambient in nature. -
PCM
Pulse Code Modulation. A method of converting analog audio to digital data, and back again. Used in some industrial Hi8 camcorders and consumer VCRs. - Record Equalization
Optimizing the amplitude of high frequencies for better record/playback response. - Saturation
The point at which a tape reaches maximum signal acceptance, beyond which distortion occurs. - Signal to Noise Ratio
A ratio between the actual audio signal strength and any noise in the signal. The higher the number the better. - SP/EP
Tape speeds. SP: Standard play, EP: Extended play. - VU Meter
Volume Unit meter. Measures average sound intensity with a moving needle or bank of LEDs.
