The different woods used for the back plates of acoustic guitars are often compared by guitarists for their sound qualities, but these comparisons are rarely done under blinded conditions. For this experiment, six steel-string acoustic guitars were built to be as similar as possible except for the woods used for the backs and sides. Bridge admittance measurements and spectral analyses of acoustic recordings revealed small differences between the guitars in their low-frequency modes. Fifty-two experienced guitar players rated the guitars for sound quality, playability, and other perceptual attributes while wearing welder’s goggles to prevent visual identification. The guitars received on average similar ratings for sound quality and playability. A factor analysis showed that the other perceptual attributes clustered around the dimensions of “clarity,” “warmth,” and “loudness,” which were all positively related to perceived sound quality, and did not differ significantly between the guitars. An ABX discrimination test performed by a subset of 31 guitarists showed that guitarists could not easily distinguish the guitars by their sound. Overall, the results suggest that the woods used for the back plate of a steel-string acoustic guitar have only a minimal influence on its perceived sound, despite varying greatly in price, prestige, and sustainability.