What is Signal-to-Noise Ratio?
If you’ve ever tried to fine tune the reception of an AM/FM ratio so you could better hear the station amidst the static, you have an understanding of what signal-to-noise ratio is. In communication, the signal is the information you want to get to your audience. The noise is pretty much everything else: all the extraneous information that doesn’t serve to communicate your message.
Every communication is composed of a series of steps. A communication begins with the creation of a message by one party, followed by the transmission of that message to another party, and ending with that party’s reception. At each of these three stages, the signal degrades as noise is added, akin to the classic playground game of telephone.
When thinking about signal and noise, it is wise to consider the entire system involved with the communication rather than just the transmission itself. Your ideals, desires, and cultural assumptions, as well as those of your audience, are also an integral part of the system. It is impossible to completely drown out noise: as you only know your own thoughts, it is impossible to entirely infer what your audience knows, doesn’t know, and believes.
The higher the signal-to-noise ratio of your design, the more clearly your message is communicated to those viewing your design. Your goal with every design should be to strive for the highest S/N possible.
Origins of Noise
• The inclusion of irrelevant information, which can creep in when too much effort is given to provide the full story of the design.
• The overuse or underuse of jargon, which could lead to confusion with unknown words and a loss of explanatory ability, respectively.
• Cultural differences, since what people really hear is based on what they already know and what they want to hear.
The Golden Rule of Avoiding Noise
The best way to make progress is through considering your audience rather than just yourself. Consider these few questions about your audience before communicating, and you will be well on your way to strong signals and weak noise:
• What wrong assumptions about your design might they form based on their prior experiences?
• What do they know already?
• What do they want to know?
• What do they need to know?
Communication is most certainly not a one-sided process: both sender and receiver have desires that they want to act upon and information they want to receive, and noise helps neither. There is no such thing as an “excellent communication” that doesn’t actually transmit the right signal to its audience: no matter how many textbook guidelines you follow, if the audience doesn’t get it, you need to change it so they do. With practice, you can get closer and closer to an ideal seamless communication that contains no noise and gives the receivers exactly what they need.