Dust

I use a vacuum pump to remove all the air from the room whenever I am not actively listening. This stabilizes pressure on both sides of all vacuum tubes leading to massively increased tube life. Some of my tubes have now lasted longer than since the date of manufacture. Then all the air returns via Biosafety Level III filtration systems. BSL3 is the new audiophile gold standard. They will tell you it doesn’t matter but I can say for a fact the filters are directional.

I don’t like to use dust covers. They trap volatile polymers outgassing from dielectrics leading to corrosion in delicate electronics. So I get up every 15 minutes and painstakingly remove the dust one speck at a time. LED headlamp and blue-tack on a Q-tip. I call this putting the anal in analog.