[YuccaGloriosa]

I don't think so. If I pour hot water into a mug from the kettle, it sounds different with cold water with all the same equipment, room etc

[dghlsakjg]

That's my feeling as well. I can hear when the hot water has reached my shower.

[grilledchickenw]

I hear the same with my shower, but I'd wager most of the change in sound would be to do with pressure change between the hot and cold source.

[bjelkeman-again]

I turn on the tap in the sink in the bathroom, when waiting for the hot water coming from the cistern. The water in the pipes have cooled down over night. I can hear the difference in the sound when it splashes in the sink, when it is hot. So yeah.

[Enginerrrd]

That doesn't surprise me at all. I can tell hot water from cold by how it looks when you pour it, (steam aside).