The so-called pedal note, frequently used in many orchestral scores for instance on trombone parts, is the first regime (lowest frequency) played by bass brass instruments. Because their frequency is far from any acoustic resonance frequency of the instrument (a few semitones away), pedal notes have been intriguing scientists for decades. Various hypotheses have been proposed throughout history to explain this characteristic. Almost a century ago, it was commented on by [1], and has been later explained as the consequence of nonlinear coupling of higher acoustic modes whose frequencies are close to harmonics of the playing frequency [2]. We show here that using advanced numerical methods for nonlinear dynamical systems allows us to finally demonstrate that standard models of sound production in brass instruments explain the emergence of pedal notes. This analysis also explains why pedal notes are played preferably at fortissimo level rather than pianissimo. Finally, we show how most recent studies have revealed, for certain brass instrument geometries like the tuba family, the existence of so-called ghost notes lying between the pedal note and the second register.