vigyan bhairav tantra
This dhāraṇā uses a continuous sound — a struck bell, a singing bowl, or any sustained tone — as the object of attention, following it as it fades into silence and then following the silence itself. The instruction is to listen to the sound's resonance all the way to where it disappears, then rest in the quiet that follows, repeating as it's played again. Because the object is entirely non-verbal, it gives the internal monologue nothing to attach to.