Yeah, figured it'd be a long shot (or at the very least require another coupler / mic located near the measurement rig). But it sounds like measuring FR it isn't as important? I'm not super worried about THD other than avoiding problem areas for the driver (e.g. resonances) when EQ'ing.

Closest thing I've ever heard to "neutral" in a headphone is the 6XX. Favorite stock tune was the Arya. Best sound overall is an L700 with EQ and Blue tac mod. Best sound for shooters is HD800s (love how it understates the bass allowing more important sounds to stand out). Favorite headphones...

Crazy thought, but can we just get a calibrated omnidirectional mic added to capture ambient noise and substract that from the measurements? Otherwise it seems like you'd need to go down endless rabbit holes trying to remove every source of environmental noise.

Is it possible to join this tour? Like in a couple months? I've got measuring gear being shipped and I'd like to use these to calibrate them.

Edit: just to note, that video is the reason I ordered the SPL calibrator =). It was very useful! Are the THD measurements consistently off? Like does it always show say +3 db extra distortion or extra distortion at certain frequencies? Or is the difference random?

Here's what I have on order so far: SPL calibrator: https://www.aliexpress.com/item/32894240716.html?spm=a2g0s.9042311.0.0.5d144c4dPcHePv Coupler, Type 1: https://www.aliexpress.com/item/4000073069259.html?spm=a2g0s.9042311.0.0.5d144c4dPcHePv Artificial pinna w/ plate...

My thoughts into the matter went as far as this: 1. Database everything BUT every entry needs to be from a verified account. If someone starts dumping "bad" data, their entries can be hidden and/or deleted. 2. We'd need a few "standard" devices. Say before we make your measurements published...

Is this still the main thread to discuss reasonably accurate and not outrageously expensive DIY measurement rig setup? (I ordered a coupler & pinnae yesterday and hoping to be able to contribute to measurements). If so, I plan on documenting and sharing what I learn getting my rig setup here =)...