Sound Quantity and Quality of Sampo 3065 Combine Harvester

Noise is considered as one of the most debilitating conditions in farming operations. In this study, a number of factors affecting the noise generated by Sampo 3065 combine harvesters were evaluated. Factors were engine speed and gear ratio for combines with and without original cabins. A factorial experiment arranged as a completely randomized design with four replicates was used. Results indicated that loudness level correlated strongly with A-weighted sound pressure level (R2=0.99) but had a weak relationship with linear sound pressure level (R2 = 0.60). Other results showed that original cabins decreased 30.5, 22.8 and 5.4 percent of the loudness level, A-weighted and linear sound pressure levels, respectively. Mean value averages for loudness level, A-weighted and linear sound pressure levels for high engine speed were 6.9, 9.1 and 11.1 percent higher than those at low engine speed.