Signal-to-Noise Ratio (SNR)
Definition
The ratio between the level of the desired audio signal and the level of background noise in a system, measured in decibels. Higher SNR means a cleaner recording with greater useful dynamic range.
In Simple Terms
How much louder your actual audio is compared to the background hiss of your equipment. Higher is better. A good audio interface with a high SNR means cleaner recordings, especially for quiet instruments.
In Practice
A high-quality preamp with an SNR of 110 dB allows very quiet instruments to be recorded at safe levels without audible hiss, even when substantial gain is required.