It’s not that common to hear a true soprano in chart music, as a lot of divas prefer to stick to alto registers to achieve more soulful timbres. In this case, though, Kiesza’s performance, ranging all the way up to top ‘G’, really works for me, making something of a production hook out of the resultant ‘hollow texture’ — you get lots of bass and treble notes, but very little happening in the middle registers. And by virtue of this textural hole you can easily hear some great examples of filtered noise being used as a transition effect. Notice in particular how extended each of the filter sweeps is: the rise at 0:53 lasts at least eight seconds, while the falls at 1:02 and 1:18 are almost twice that length.
If you’ve not experimented with this kind of thing before, it’s ridiculously easy to do with almost any modern soft synth. Just use a single oscillator with white noise selected as its waveform, route that through a filter set to band–pass mode, play a MIDI note to trigger the noise, and then sweep the filter’s cutoff frequency. Depending on the slope and resonance of the filter you use, you’ll get a different noise tone — to emulate the flavour used in this song I’d suggest starting with a 24dB/octave type, and only a touch of resonance to keep the emphasis peak from ‘whistling’ too ostentatiously.