Impressions from analog electronics:

My favorite picture showing the pass-bank (8 tubes 8032) of a KEPCO BOP1000 power-supply.The power dissipated within the tubes amounts to 150W. Look at the wonderful blue light at the top of the tubes which is due to electron bombardment of the glass:

Not only chemistry can be loud and odorous - this discharge (A Leydener bottle, 80KV, 10cm length of discharge) is not really silent...