This type of software, is just a bandaid and really doesn't work very well (though it can work better with headphones). I will try to tune up my FDM 50mm headphone design so that it sounds at least as good as my original resin printed design, and then look at building a better characterization rig. This hobby work of mine goes slowly, but I appreciate your suggestion. I have some nice little capsule mics I was playing with that would work nicely, and I have a datasheet for those that probably includes a curve. However this little adventure has encouraged me to consider building the little head dummy. Do look at my linked tweet for those FR curves. But for my relative tests I just shoved my podcast mic, Audio Technica AT2005USB up to the center of the driver on one side of the headphone. What I wanted to do was build a little headphone test dummy head. But since I don't have a calibrated microphone, it is more useful for doing relative comparison between my headphone designs than it is for providing absolute numbers. It was only today that I did any kind of frequency response testing. For the original set I just compared them to my friend's expensive headphones.

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