I had a total of 5 Linux machines running here at home and 2 of them locked hard sometime near midnight UTC.

One is my main server running Debian Etch and had been up for several months. It had not crashed once since replacing the hardware over a year ago. We were watching a recording on MythTV when it locked-up. I walked over to my workstation, running Ubuntu Intrepid, to restart the backend and it was also locked-up hard.

Very bizarre until I looked at the logs and did the math. Both logs end just before midnight UTC.

Audio is completely subjective. Do whatever makes your ears the happiest. Personally, I grew up in the 80s and 90s listening to all my music through a tube amp. When I finally "upgraded" to more modern technology, I really wasn't paying much attention. At some point I came across my admittedly medium-fi 6V6-based tube amp again and got the itch to fire it up to see if it still worked. It wasn't until then that I realized what I was missing.

It's all in the ear of the beholder and no spectral analysis is going to change that for anyone.