It's strangely quiet down here, too. The new furnace has no pilot light. I'm accustomed to hearing the constant hhhhhhhhhh of a pilot light. Add to that it's a dual stage furnace, meaning the first half of the cycle is half-burn - if it even needs to get to full-burn - so from upstairs we'll rarely hear it.

Hafta put on music just to fill the aural space!