There's no knob to turn for microphonics or noise. What about all the other variables that may or may not apply to you? Can you show me a sound stage knob? You can have all your boosts, compressors, EQ, noise gates, cabling, etc. and I'll just tube roll instead and play guitar to amp.
You expect someone to hear a difference in tubes over a very narrow range of frequencies? You covered like 20% of what a human ear can hear and nothing that we can feel (to no fault of your own). What's the frequency range of your speakers? You actually think that's a fair example of what a tube can do when you've placed limitations because of the equipment you chose and what's being played? I know you're doing it in good faith but it's deeply flawed.
There's lots of people who've measured this stuff decades ago and know what they're talking about. All the tube naysayers don't have a single measurement to back up what they say. Just show me measurements that these tubes are all the same and explain the methods they were done with.
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