emaidel was right about the Hi-Fi Tuning fuses

[Feanor]

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Apparently, the ability to hear transcends a persons ability to hear the full range of frequencies.
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I believe this for sure. I'm pretty old, (66), but I've had limited high frequency hearing for at least a decade. On top of that, I experience continuous tinnitis.

I hear nothing about 10 kHz, stone deaf for the top octave. I've had relatively limited frequency range for a long time but I'm not sure how much for how long since I wasn't tested. As for the tinnitis, I've had that for over 40 years. It is continuous in both ears, but a little stronger in the left. It has gotten a little bit worse in recent years.

Notwithstanding these auditory handicaps, I can hear subtle differences in components. Well OK, I don't hear much difference in case of power cords.