A bass drum is a low-pitched membranophone that can mark pulses and accents in bands, processions, and popular-music ensembles. Its size, drumhead, and striking technique shape attack and resonance. In Mexico, the word bombo does not always designate one instrumental model, so the documented region and ensemble matter. This category gathers records identifying its participation and enables comparison of rhythmic roles and playing techniques. Credits and photographs help distinguish it from a tambora or the bass drum of a modern drum kit. Similar low-frequency sounds alone do not establish that the same instrument is being used.