The School Choir's Balance Problem
A 28-voice school choir rehearses a Botswana folk song arranged in three parts: soprano, alto and a bass line sung by 6 older boys. In the school hall the balance sounds good, but at the district competition the choir performs in a hall with a high vaulted ceiling and a wooden floor. The conductor notices that the bass line disappears in the louder verses, the altos sound muddy, and the sopranos' final sustained note rings on for about two seconds after the choir stops. Two of the six basses stand at the back of the group and are the youngest and least confident singers. The conductor has one 20-minute rehearsal in the competition hall before performing.
1. Explain why the bass line disappears in the new hall, and give two practical adjustments the conductor can make in the 20-minute rehearsal.
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The bass line disappears for two reasons. First, a high vaulted ceiling and hard wooden floor produce a long reverberation time, so sound from all voices overlaps and the quietest part (6 basses) is masked by 22 upper voices. Second, the two least confident basses are at the back, furthest from the conductor and behind the other singers, so their sound is absorbed and they cannot hear themselves or the conductor clearly. Practical adjustments: (1) reposition the basses at the front or on the outside edge of the formation, and spread the six across the back of the front row so their sound projects directly into the hall; (2) reduce the upper voices' dynamic in loud verses and ask the basses to sing with firmer support, then test the balance by having the conductor stand at the back of the hall while sections sing alone. A third option is to shorten final chords and use a crisper cut-off to manage the 2-second ring.
2. The sopranos' final note rings for about two seconds after the cut-off. What does this tell you about the hall, and how should the conductor change the ending?
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A two-second ring after the choir stops indicates a long reverberation time (roughly RT ≈ 2 s), typical of a large hard-surfaced hall. The sound decays slowly because hard surfaces reflect rather than absorb energy. This means fast passages and crisp articulation will blur, and a sustained final note will overlap with whatever follows. The conductor should shorten the final chord's written value, use a clear preparatory beat and a decisive cut-off, and consider ending on a shorter note or a crisp rhythmic gesture rather than a long sustained chord. The choir should also articulate consonants more strongly so the text stays clear despite the reverberation.