Three Microphones, Two Speakers, One Kaumātua
Kōwhai College is holding a 90-minute concert in a wharenui that seats 100. Fourteen tauira will perform: a whakaeke with 14 voices, three waiata ā-ringa with guitar, a kōauau solo, and a whaikōrero by a kaumātua. The equipment available is two dynamic microphones, one condenser microphone, one guitar DI, a powered mixer with 8 channels, two speakers on stands, and one monitor. The student sound operator has run the desk twice. Doors open at 6:00 pm, karakia at 6:30 pm, and the kaumātua has asked that no sound checks happen after the karakia. The last concert produced feedback at around 2 kHz whenever the condenser was turned up, and half the audience at the back could not hear the kaumātua. A tangihanga means the kaumātua may arrive only ten minutes before doors open.
1. Allocate the available inputs. Justify your prioritisation and say explicitly what you would leave unamplified.
Read the worked answer
Priority rule: intelligibility of speech beats volume of music. A hundred seats in a wharenui with a hard floor is a small room; most acoustic sound will carry. Amplification should fix what is broken, not reinforce what already works.
Allocation:
- Channel 1 – dynamic mic, kaumātua. Closest to centre, stand set before he arrives, high-pass filter engaged to cut floor rumble, gain set from a stand-in.
- Channel 2 – dynamic mic, kaitātaki/lead voice for the waiata ā-ringa only.
- Channel 3 – condenser, kōauau solo. Placed at least 2 m in front of the performer and positioned so neither speaker points at it.
- Channel 4 – guitar DI.
- Channels 5–8 – spare. Leave them empty.
Left unamplified: the whakaeke. Fourteen voices in a 100-seat room will fill it; miking a large group with one microphone produces a thin, uneven sound and raises the feedback risk. Better to ask them to project and to stand in a shallow arc.
Left unamplified also: the karanga/karakia and any group singing that the audience is joining. Amplifying a room that is already singing creates a confused sound field.
Trade-off acknowledged: the back row missed the kaumātua last time because his voice was never the loudest source in the room. Making him the first input, set on his own, fixes the actual complaint rather than turning everything up.
2. Explain how you would prevent the 2 kHz feedback and how you would set the kaumātua's channel when he arrives only ten minutes before doors open.
Read the worked answer
Why 2 kHz. That band is where small wooden rooms and lightweight microphone stands tend to resonate, and it is also where a condenser's presence peak sits. The condenser was probably not the cause - it was the trigger that pushed a system already near its limit over the edge.
Prevention:
- Place speakers forward of all microphones; nothing behind the mic line.
- No monitor for the condenser channel. The kōauau player can hear the room.
- Ring the room out before doors: bring the master up slowly with the condenser open until it just starts to sing, then pull that band down 3 dB on the EQ. Do this before the karakia, not after.
- Cap the master fader with tape so nobody 'just nudges it'.
The late kaumātua - a prepared protocol:
- Before doors, put a student with a similar speaking volume on the mic and read a paragraph of a whaikōrero. Set the gain on that, mark the height on the stand with tape, and write the fader position on a label.
- When he arrives, ten minutes is enough for two sentences: 'tena koe, stand here, speak at this level'. No full check, which respects his request.
- Brief a second person to watch the desk for the whole whaikōrero so one operator is never alone.
- If feedback starts, the response is to pull that channel down immediately, not to hunt the EQ. Intelligibility of a quieter voice is better than a squeal.