Every room has its own sound. Between two parallel walls, and between floor and ceiling, certain frequencies fit exactly: they resonate and sound louder than the rest. When you record voice, you want to hear the voice, not the room.
This calculator works out which resonances (room modes) occur in a rectangular space based on its dimensions, and suggests a concrete EQ move per frequency, with cut and Q factor. You set whether you are recording a male or female voice, and click where you stand or sit, because your position determines how much pressure a resonance builds up.
Not a ready-made fix, but a starting point: a way to understand how a room colours the sound, before you start treating it or reaching for the EQ.
