What does it mean to have a unique group sound? Is such a thing quantifiable? If so, are there noticeable differences between groups, and any correlations to the time each group spends together? It is important to note a caveat right off the bat: music is generally understood to be created by and listened to by humans, and thus any attempts at quantifiable answers to the above questions will be, at best, orthogonal to its main purpose. It is also clear from anecdotes and interviews with professional musicians that qualitatively distinguishable characteristics of group sound and interpretation absolutely do exist and are noticeable to the listener. Paul Katz, cellist of the Cleveland Quartet, describes the multiple layers of such a group identity: “When one spends that many hours per day and years together, there is a meshing of taste, an unspoken unification of musical values, an intuitive understanding of each other's timings and shapings, and even a merging of how one produces sounds, makes a bow change, or varies vibrato, that is deeper than words or conscious decision making.” This dissertation concerns itself with the general question of whether or not it is possible to detect and define, in a quantifiable sense, the patterns and elements of a unique group sound identity, specifically in the intonation domain. Original research was carried out, consisting of recording four string quartets with high-quality equipment under controlled conditions, to begin to answer this question.