The present study explored whether musicians could (1) differentiate among the timbres of bass tubas of a single design, but constructed of different materials, (2) determine differences within certain ranges and articulations, and (3) possess different perceptual abilities depending on previous experience in low brass performance. Findings indicated that (1) tubas made to the same specifications and constructed of the same material differed as much as those of made to the same specifications, constructed of different materials; 2) significant differences in perceptibility which occurred among tubas were inconsistent across ranges and articulations, and differed due to phrase type and the specific tuba on which the phrase was played; 3) low brass players did not differ from other auditors in their perception of timbral differences.