Sorry, I mistakenly referenced a post in the moderators section.It's not allowing me to access the link you posted.
No, the line-out to line-in will be fine. If the soundcard cal file drops off quickly at 18K or is jagged, then that's as high as you should measure. If it tails off smoothly and slowly, then you can go higher. (read this thread through on mic preamp calibration methods)....... created the cal file by going line-out to line-in rather than from line-out to mic-in. Could that be a potential problem?
If I recalibrate the soundcard/pre using the mic-in, should I engage the phantom power button?
No, you don't engage the phantom power button. It is power for a microphone circuitry.If I recalibrate the soundcard/pre using the mic-in, should I engage the phantom power button?
Please explain? I don't see that in the generic files? The cal files all show negative values as you get to the extremes of bandwidth...It surprises me that either of these mics would roll-off early when the generic cal files show lifted response from about 10KHz on up.