Theoretically, as I noted, transmission line effects are possible, but would be at such high frequencies as to have no possible audible effects.
Far far more likely, would be simple, and practical effects, not geoffkaits physics babble.
Fuses and fuse holders are mechanical devices. It is possible that the combination of the fuse shape and the holder shape is more conducive to lower resistance in one direction. However, don't get caught up in the trap for AC fuses that less resistance is always better.
Ditto, fuses are thermal devices, a better mechanical connection in one direction coupled with a fuse defect resulting in asymmetrical heating could cause more thermal modulation in one direction. However, unless the fuse is pushed to its limits and the amplifier has some serious serious design issues, thermal modulation of the AC fuse is not going to be audible.
Far far more likely, would be simple, and practical effects, not geoffkaits physics babble.
Fuses and fuse holders are mechanical devices. It is possible that the combination of the fuse shape and the holder shape is more conducive to lower resistance in one direction. However, don't get caught up in the trap for AC fuses that less resistance is always better.
Ditto, fuses are thermal devices, a better mechanical connection in one direction coupled with a fuse defect resulting in asymmetrical heating could cause more thermal modulation in one direction. However, unless the fuse is pushed to its limits and the amplifier has some serious serious design issues, thermal modulation of the AC fuse is not going to be audible.