Signal-to-Noise Ratio (SNR) Explained
Product specifications often list the signal-to-noise ratio, sometimes written as "SNR" or "S/N," but what does it mean? While the math behind SNR is technical, the concept is not, and this value can impact a system's overall sound quality.
SNR compares the level of a signal to the level of noise. In other words, it compares the ratio between the relevant (wanted) and the irrelevant (unwanted) information. It is most often expressed as a measurement of decibels (dB). Higher numbers generally mean a better sound quality, since there is more useful information (the signal) than there is unwanted data (the noise).
A decibel is a logarithmic ratio in which every 20 dB represents a factor of 10. For example, going from 80dB to 100dB means increasing by 10 times. This means that an audio component having an SNR of 100 dB will have 10 times less noise than one that has 80 dB. The chart below shows how different dB ratios actually compute.
For illustration, let's say that you're having a conversation with someone in a kitchen that also happens to have a particularly loud refrigerator. Let's also say the refrigerator generates 50 dB of hum (consider this as the noise) — a loud fridge. If the person you are speaking with chooses to converse in whispers (consider this as the signal) at 30 dB, you won't be able to hear a single word because it is overpowered by the refrigerator hum! So, you ask the person to speak louder, but even at 60 dB, you may still be asking them to repeat things. Speaking at 90 dB may seem more like a shouting match, but at least words will be clearly heard and understood. That's the idea behind signal-to-noise ratio.
Our PecanPi® products have a SNR of 130 dB or 3,162,277 : 1.