Flex and complex harmonics in the new 12'9"

Once a new board is built we test the flex and the harmonics of the board be bending it and hitting it to see how it resonates and flexes. This board when struck set up at least two vibrations: a fast one like a buzz and a slow one whih travelled visibly up and down the board like a pulse. It's a little bi hard to see in the video below because the faster vibration isn't visible and sometimes only two of the four observable pulses can be seen on the clip, but here it is anyway: