The paper discusses how particle size and texture influence acoustical properties of particle boards. Single layer boards were produced from different particle sizes: 6.14-2, 1.5-1, 0.6-0, 0.237-0. The middle layer of 1st middle layer board was manufactured from particle sizes 6.14-2, and the outer from 0.237-0; the other board had middle layer made from particle sizes 4-2, and outer from 0.6-0. Tests were carried out, with the help of testing chamber. Interior of chamber was covered with sound absorbing foam, and speakers were mounted. On the outer surface of the chamber, the sample with the sample accelerometer was mounted, in a distance of 0.5 m a microphone was positioned to detected sound waves, which went through the board. It was discovered that different particle sizes and free spaces between particles are significant factors for acoustical properties of single layer boards. The particle size has a very important influence on single layer boards, because it determines the porosity of the board. Porosity also has an effect on sound transmission through the board itself. A single layer board made out of larger particles, has free space among particles. These free spaces allow energy to be easily absorbed and converted into heat. In boards from finer particles, more sound pressure bounces back into testing chamber. Particle sizes and variety of free spaces in multi-layer boards dictate differences among multi-layer boards. Particle sizes varying through the multi-layer board also dictate porosity of the multi-layer board. Porosity of the multi-layer board also influences sound transmission between different layers inside multi-layer board.