$hands on sound diffraction$

$hands on sound diffraction$

#Hands on sound diffraction driver#
#Hands on sound diffraction plus#

It should not come as a surprise that a sound wave will bounce off a hard surface like a flat concrete wall.

#Hands on sound diffraction plus#

One plus negative one (the top two plots) equals nothing (the bottom plot). For example, the red stars show the values at one moment in time. The bottom plot is the result of adding the signals shown in the top and middle plots, moment by moment in time. One plus one (the top two plots) equals two (the bottom plot).įig 2. The sound from the headphones is in theory identical to the sound coming to your ears from outside the headphones, except that it’s opposite in polarity, so the sum of the two sounds is nothing.)įig 1. (This is how noise-cancelling headphones work. HOWEVER, if you have a high pressure and a low pressure arriving at the same time in the same place (for example, at your eardrum) then they cancel each other and, if they have the same magnitude, your eardrum won’t move at all and you won’t hear anything.

$hands on sound diffraction$

Similarly, if you get two low pressures arriving at your eardrum, it will be pulled further out of your head than if only one of them was present. So, if you have two high pressures arriving at your eardrum, it will be pushed farther into your head than if only one of them arrived at your ear. If you have two sound sources, their pressure differences (relative to the average pressure) add. The red semicircles show the high pressure zones that expand outwards from the front of the loudspeaker. The green semicircles show the low pressure zones. The grey thing is a very, very wide loudspeaker cabinet.

#Hands on sound diffraction driver#

The red thing is a piston which is basically the way we like to pretend a loudspeaker driver (like a tweeter) behaves.

$hands on sound diffraction$

In order to create a low pressure, we pull it inwards, as is shown in the animation below. One way to create a high pressure is to take a loudspeaker driver and push it outwards. When your eardrum moves in and out, you hear sound. If the instantaneous pressure is lower than average, then your eardrum is pulled out of your head. If the instantaneous pressure is higher than average (which happens to be the same as the pressure inside your head), then your eardrum is pushed into your head. At its most fundamental level, sound is just a relatively small, relatively fast change in barometric pressure. #15 in a series of articles about the technology behind Bang & Olufsen loudspeakersīefore we start talking about curves and corners, let’s have a quick review on the concept of interference.

$hands on sound diffraction$