This paper builds on initial evidence of First Language influence on brass playing presented in Heyne and Derrick (2013) [13] by indicating how tongue positioning might affect trombone timbre. Ultrasound imaging of the tongue was used to compare vowel production and sustained trombone notes for three participants, one each of New Zealand English, Tongan and Japanese, whose musical production was also analyzed acoustically. Comparison of the sound spectra produced by two semiprofessional players shows that the player using a higher, more retracted tongue position displays a larger component of high frequencies in the produced sound spectrum. We believe that this could explain why brass players can notice differences between players from different language backgrounds.