Crooner
Singer in the soft, microphone-based style.
What it means
Crooners are singers who sing with a soft, unforced voice directly into the microphone. The style arose when electric amplification became generally available: whoever no longer has to compete with an orchestra can sing very quietly, stay close to the speaking voice, and make the finest shadings audible — breathy sounds, delays, small bends of pitch. The microphone is here not an aid but part of the technique.
Musical use
The style shaped the popular music of the twentieth century, especially the repertoire of American songs with big-band or orchestral accompaniment. Musically it has a reciprocal effect on the shaping: because volume no longer has to be worked for, the treatment of the text moves into the foreground, and the phrasing may depart far from the notated rhythm. Compared with classical singing, which carries without amplification and therefore depends on resonance and volume, closeness is in the foreground here — the impression that someone is speaking directly to the listener.
The singing style arose with the introduction of the electric microphone in the late 1920s, which made quiet, close singing possible. Bing Crosby and later Frank Sinatra shaped it.
Performance practice
Work deliberately with the distance from the microphone: closer gives more warmth and depth, farther more space; large jumps in volume are balanced by drawing back. Watch for sibilants and plosives and sing slightly off-axis to soften them. Support the breath despite the low volume, otherwise the tone becomes powerless and the intonation uncertain. Practise the phrasing against a stable tempo so that the delaying seems shaped and not accidental. Settle the settings with the sound engineer beforehand, because the style depends directly on the reproduction.
Bear in mind that this way of singing does not work without amplification: in a room without a sound system the tone becomes powerless, and the fine shadings disappear. Check the equipment and the settings before the performance and try out the distance from the microphone. Work on breath support even though the singing is quiet, because intonation and tone colour suffer otherwise.