Well, my opinion is primarily based on an A-B test, as with all audio equipment. I do have quite a few good instruments, for example Neutrik A-2 D Audio Test & Service system, THD, IMD, phase etc. for measurement, as well as several generators, oscilloscopes, 6.1/2 digit HP multimeter. But the most important is the comparison test with switching. Fortunately, I have a friend with a very serious recording studio and several trained musicians. (I was a sound engineer in many rock and jazz bands when I was young.) I am 70 years old now. I always listen to their opinions. My "obsession" is that noisy things always sound bad. Maybe I have a prejudice about LF... and TL071 etc. from times. I remember building a 24-channel mixing desk for my band in 1980. Then I selected all the parts according to their sound. For example, there was the LM301 in both a plastic case and a metal case (military) version. Both were made by NS. The metal casing (M) had an incredibly nicer sound. Although according to the catalog data sheet, only the operating temperature range is different. My test material was a recording of jazz music recorded with a professional microphone from a Uher Report tape recorder, the power amplifier Crown DC 300 A The monitor speaker is a custom-built Isophone KK-10 dome tweeter. Also, the square signal (and sawtooth signal) transmission from the function generator. Checked with an oscilloscope. At my previous job, I learned what the various transmission distortions of a square signal mean. Transients constantly appear in the music, and very rarely a clear tone. That's why I wrote that I already bought several types of OP series FET input operational amplifiers, but I haven't had time to test them yet. (Unfortunately, my Chronic Lyme disease takes a lot of time, but I'm not young either.) For example, I recently had to repair the ATC monitor (active) speakers of my studio friend. I'm already retired, but my hobby is the same as my job, I can't stop. This makes it easier to bear the severe pain caused by my illness. I wish everyone good health!
maybe larger values suited to audio
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