The grind and creak of mismatched gears. It wasn't loud, not by any stretch of the word, and yet he heard it very clearly, felt it even. He could almost feel that unpleasant sound, as though it were such an awful utterance that it should reverbate through him, chilling his bones.
He checked, first, his own pocketwatch. She was silver - he'd made her himself some night long ago. He knew how to fix it if he could just find the error and replace errant or loose pieces before the mechanisms were irreperably damaged.
But no, his watch was working like a charm. He was methodical as he checked through every clock in the shop, even half-finished mechanisms that were not yet complete.
The sound grew louder, and he could hear the slight creak over the steady click of the cogs still working. He felt it in his chest, in his very skull, and wanted to scream as he could not locate the source of that thrice-damned NOISE.
Louder still, he could hear occasional whines as metal pieces were pushed from their places by already unattached cogs, setting the clockwork into further discontent.
The noise was unbearable now, vibrating through his very skull, louder and louder until it was a screech of tiny, broken cogs and metal-on-metal.
He keeled forwards, hitting the floor with a crash that could be heard two doors away.
It was the apprentice that found him the next morning. His skull had broken on the impact, sending cogs, tiny barrels and metal shards across the floor around him.
Though cogs could be replaced and metal plates repaired, the clockmaker was too damaged to consider - the cost was not one affordable.
At the very least, the cogs that had run his chassis and limbs could be cannabalised for further use. "Cost-effective" was the phrase turned.
The apprentice didn't mind. He continued his work in silence. His master had been a mere machine: he was nothing to miss.