Choral Configuration: An Overview of Research and Implications for the Choral Music Educator

Acoustical Placement

Acoustical placement, also called voice matching, is associated closely the work of F. Melius Christiansen (Decker & Herford, 1973), Robert Shaw, and Weston Noble (Giardineire, 1991). These pedagogues have suggested that the placement of individual singers within the ensemble based on voice color and weight can enhance blend and reduce intonation issues. Several empirical studies have provided evidence in support of this theory (Ekholm, 2000; Folger, 2002; Giardineire, 1991; Killian & Basinger, 2007; Tocheff, 1990; Woodruff, 2002), although procedural inaccuracies bring some of these findings into question (Ternström, 2003).

Some researchers have found that acoustical placement makes a perceptible difference in choral blend and tone. Killian and Basinger (2007) discovered that collegiate music majors (vocal and instrumental), and collegiate nonmusic majors were largely able to perceive a difference in blend between matched (acoustically placed) and unmatched (randomly placed) choral configurations in a collegiate choir. Most participants indicated a preference for blend when the ensemble was in acoustical placement. In another study investigating acoustical placement with collegiate choirs, Tocheff (1990) asked experienced choral conductors to rate a variety of aspects of choral tone in matched and unmatched placements. Based on the preferences of the adjudicators, he concluded that multiple aspects of choral tone were positively affected by acoustical placement, including intonation, blend, rhythmic accuracy, and diction. However, Ternström (2003) noted that, given that adjudicators were asked to rate 6 variables over a total of 32 trials using a complex system, there may be reason to question the validity of these results.

Giardineire (1991) further analyzed the process of acoustical placement. He closely observed and recorded Weston Noble’s process in voice matching a choir at Luther College. He then provided over 100 choral experts with the recordings, but not with Noble’s final decisions, and asked them to rate the recordings and answer questions on how they might place the singers. Giardineire not only recognized that many elements of the process were subjective in nature but also found that the majority of the choral experts who participated in his study agreed with Noble’s decisions. His in-depth study of Noble’s process also provided some insight into the elements of voice matching through both similar matches (voices of similar quality placed together) and complementary matches (voice of contrasting quality placed together to complement one another). He additionally outlined the process of identifying a core trio within the section and adding one singer at a time until the optimal placement was found for each singer.

Other researchers have examined the effect of acoustical placement on individual vocal production. Folger (2002) moved undergraduate sopranos and basses into multiple positions and measured their individual vibrato rates. He found that vibrato rates changed as the positions changed and suggested that this finding may lend credence to the idea that placement affects the vocal production of each member of the ensemble. Individual undergraduate performers were recorded within a choir arranged in both random and acoustical placements in Ekholm’s (2000) study. The recordings were then evaluated by choral conductors, voice teachers, and nonvocal musicians, who were asked to rate the quality of the individual voices. Voice teachers expressed a consistent preference for individual vocal production in acoustical placement. Taken together, findings from these studies appear to support the claim that acoustical placement may affect the overall choral sound as well as individual vocal production.

Formation and Spacing

Additional factors of choral configuration include formation and spacing among singers. Lambson (1961) examined four choral formations: section blocks, mixed quartets, scatter (placement based on voice matching with no regard to part), and random (no consideration for voice part, acoustical placement, or any other relationship). In each formation, adjudicators were asked to rank their preference for a homophonic and a polyphonic piece in a live performance and in a recording of a collegiate choir. For homophonic music, his participants expressed a preference for mixed quartets in both the live performances and the recording. For polyphonic music, however, participants preferred section blocks in the live performance and mixed formation in the recording. Based on this information, he proposed that conductors consider mixed formations, especially for homophonic music and with advanced choirs that can sing independently. However, he suggested that changes to formation may have less of an effect on choral sound than had been previously thought.

Daugherty (1999) conducted an experiment similar to Lambson’s, but with high school singers. He limited his configurations to section blocks and mixed formations but added the variable of spacing. He used close spacing (approximately 1 inch shoulder to shoulder), lateral spacing (approximately 24 inches shoulder to shoulder), and circumambient spacing (lateral spacing with a vacant row between singers) with each configuration. Auditors then listened to matched pairs of recordings and chose their preference from each combination. Choir members and auditors both preferred the overall choral sound in mixed formation. Both groups also expressed a preference for increased spacing, independent of formation. Most participants preferred lateral spacing over close spacing and circumambient over other options.

The Lombard effect is central to the discussion of spacing and its impact on choral sound. This term refers to the tendency for speakers to increase their volume or intensity when in noisy surroundings. It can also cause over-singing as individual singers increase their volume or intensity to hear themselves within the ensemble. Tonkinson (1994) found that, through verbal instructions, singers could be trained to resist the Lombard effect. Other researchers have proposed that proper spacing may prevent it altogether. In her examination of the effect of acoustical placement on blend, Ekholm (2000) noted that the Lombard effect caused singers using soloistic tone to over-sing. She hoped that acoustical seating would provide the solution but discovered that the problem persisted regardless of formation. She suggested that spacing was the best option for dealing with this tendency.

Other researchers have supported Ekholm’s suggestion to counteract the Lombard effect with optimal spacing so that singers can monitor their own voices in relation to the ensemble. Ternström (1999) examined this effect of spacing and referred to it as the self-to-others ratio (SOR). This term refers to the singers’ ability to hear themselves and other members of the ensemble at the correct ratio for the optimal sound. If singers are unable to adequately hear themselves, issues of intonation, vowel shape, and over-singing can occur. This inability to hear oneself (i.e., low SOR) can be caused by the acoustics of the room or by a choral formation that is too tightly spaced. Ternström also found that the optimal ratio is not the same for all singers or voice types. For example, he observed that sopranos generally had a higher preferred SOR than basses. Typically, the SOR will go up with an increase in the absorption of the room, an increase in spacing, or a decrease in the number of singers. Therefore, choral music educators should take into consideration the performance or rehearsal space and the number of singers in the ensemble when making decisions about spacing. Based on these data, Ternström inferred that a large ensemble should use more floor space for each individual singer, and an ensemble moving into a room that has a higher absorption rate should decrease their normal spacing.

Spacing and formation can also affect singers’ perceptions of their own sound. Atkinson’s (2010) participants showed preference for their individual tone production in mixed formation and spread spacing. In this study, Atkinson had a collegiate choir sing excerpts using both mixed and sectional formation with both close (1 inch between shoulders) and spread (24 inches between shoulders) spacing. She then had singers of that choir rank their preference in five areas: ease of singing, ease of hearing and blending with section, ease of hearing others, choral sound preference, and preference for singing. In all but one category, ease of hearing and blending with section, singers noted a preference for mixed formation. In every single category, singers noted a preference for spread spacing. It appears that spacing and formation have important implications for singer performance perceptions.

Daugherty, Manternach, and Brunkan (2012) investigated choral spacing with the addition of changes to riser height. They used close, spread, and circumambient spacing on risers of two heights (8 and 12 inches). University choir members were asked to select their preference in the categories of hearing self, hearing the choir, most comfortable vocal production, and best overall choral sound. In three of the four categories, choir members overwhelmingly preferred the condition resulting from standing on tall risers and in spread spacing. There was only one category in which the majority chose regular riser height and close spacing: hearing other members of the choir. Auditors similarly preferred tall risers and spread spacing. Consistent with Atkinson’s (2010) findings, having more space between singers positively affected singers’ perceptions and performance. Daugherty (2003) suggested that spacing may be the most impactful change to choral configuration. He speculated that spacing alone may address many of the issues that alterations to formation and acoustical placement attempt to address.

Some conductors have argued that formation has a significant impact on the tone quality, balance, and blend of the ensemble. Archibeque (2005) recommended using a variety of formations in rehearsal and in performance depending on the desired aural effect. She argued that different formations can adjust the ensemble balance by highlighting sections that are brought to the front and middle of the ensemble. She also proposed that the tone quality of the ensemble can be affected by increasing the influence of certain voice types on others. For example, she posited that placing the tenors behind the basses allowed the characteristically lighter tenor tone to affect the weight and color of the bass tone. Furthermore, she stated that different formations may recalibrate the way the choir listens, which in turn can affect blend in a performance and the attention of the ensemble during rehearsal. These thoughts echo those of other choral conductors and pedagogues (Brinson, 1996; Collins, 1999; Decker & Herford, 1973; Roe, 1983; Webb, 1993), but a paucity of empirical evidence leave these claims unconfirmed. There are certainly pedagogical benefits to the multiple formations proposed by these educators, but their perceived acoustical benefits may be subjective in nature.

Considerations for the Choral Music Educator

The wealth of knowledge available for choral music educators related to choral configuration, both empirical and anecdotal, can be used in a number of ways. Rehearsing in a variety of formations and spacing options can prepare students for the unexpected changes that may occur once the ensemble is in the performance space. Different configurations may be used based on the venue, ensemble, desired sound, and audience experience. Some of these decisions may be based on empirical research and others based on the personal preference of the conductor or ensemble members. Below are some considerations for conductors as they make decisions on configuration in rehearsal and performance.

Conclusion

The way in which choral music educators place their singers in the ensemble can have varied effects on the overall sound of the ensemble and on individual vocal production, and multiple researchers have provided evidence of this assertion. Configuration affects ensemble members, whether in rehearsal or performance. Proper configuration can lead to better vocal health for each singer by guarding against over-singing and addressing blend without altering individual vocal production. Most choral music educators would agree that they want students in their ensembles to enjoy singing and to use their voices in a healthy way. Applying knowledge gained through research into these aspects of choral configuration can help improve the experience of each singer and the sound of the choir.