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Opera singers, who sing without amplification and title project over orchestras and throughout concert halls do so primarily by fine tuning what’s called the ‘singer’s formant.’ This is basically a fancy way of saying that they learn to exaggerate resonances in their voices that are around 2khz. If you’ve worked in a recording studio, you’ll know that this is also the EQ band that your engineer will use to help your vocal cut through a mix without raising the volume. By enhancing this in our voices we project more, whether we’re using mics or not. The diaphragm is an involuntary muscle. You can only influence its behaviour by adjusting your posture and the surrounding muscle groups. By doing so we get the appropriate alignment of our bodies and engagement of the muscles surrounding the diaphragm to interact with it. This generates ‘support’ which will ideally allow the vocal fold to release tension.