Have you ever wondered how to measure the difference in ability to understand speech in a fine-tuned home theater versus a middle school gymnatorium? Hopefully, it is incredibly more pleasant and less tedious to understand the spoken word in the home theater rather than the gymnatorium, even without the screaming kiddos. But how can we measure that difference?
You guessed it! Today, I’d like to talk about intelligibility. We are all comfortable with measuring how loud a system should be, maybe even preferred equalization curves to make the system sound pleasing to the ear. But, how do we measure how intelligible the system is? I present to you the Speech Transmission Index for Public Address test, or STIPA (/stē’-pah/) for short. It is also known as the test referred to by the following phraseology: