I had sometimes used the following home made logo for SPOT (Take5) experiments : the Paul Desmond standard is indeed based on a 5 beat rhythm, which is symbolized by the "5" on the time signature of the music score. The number 4 means that the beat corresponds to quarter notes. But the 4 and 5 can also remind of SPOT4 and SPOT5. However, the logo was very basic and not professional.
The communication services started from my logo to define the new official logo of the SPOT (Take5) experiments. Looking at it closely, you can see the music score, and it is much nicer and professional looking ! Thanks ESA !