Hello
@DunninLA
I'm delighted to contribute to your understanding, as I understand it.
I don't think your brain changed. I mean, I do believe in brain burn, but for me it just means that when I switch from one IEM to another that I've been enjoying for a while I have to sit patiently with the most recently inserted unit to begin to enjoy its properties because often the sound profiles are so contrasted to one another, that I don't enjoy the new one until my brain adjusts and i begin to really pull out the qualities of the new one. I'm experiencing that right now with the UM 3DT. It has a lesser quantity of bass to the the Timeless but it is more visceral (we'll talk about that in a minute). The 3DT also has more treble extension and airiness to it, which to my ears made it appear more sibilant until I had them in a good 20 minutes and then I began to re-realize why I liked them so much and kept them. They are more V than the timeless where I find the timeless more natural and organic sounding. LOVE 'em both. If you go back and read my initial impressions and that of others where the Timeless discussion overtook this thread, you'll see that I predicted that those users who founf them sibilant, just need to be patient and let them break in - both the bass and the treble will develop. way past 150 hours with greatest shift upto 100. By and large, I think thats been experience of the users here. I've danced with these drivers a few times.
So the answer to this question lies in understanding the tech behind each type of driver and how they function. The WAY a DD and Planar produce their sound waves are entirely different and therefore they can graph the same but each move a different quantity of air and therefore you'll experience them differently. Graphs for me simply give me an indication of direction but I don't make assessments off them. So many factors affect the the final experience. Tech, material, stiffness, size of driver .... they the graphing unit only picks up FR it's doesn't account for any of the other factors.
If you've ever taken a speaker grill off and looked at the woofer inside the speaker where there's a magnet and a coil attached to a cone and the electrical impulse hits the coil to move the dome - resulting in frequencies and air pushing out from the dome. A DD is essentially a miniaturized Dome speaker - it moves more air while producing it's sound waves. The size of the DD and the material it's made of (stiffness will then have a knock on effect to things like speed and decay. It's also why many DDs, particularly those with stiff coatings (Beryllium, Graphene, etc.) benefit from break in. As they beggin to get used, they break-in and fully develop.
A Planar on the other hand is a flat stiff membrane with an electrical circuit on it literllally suspended between two magnetic fields. The electricity hits the circuit and the membrane vibrates between the magnetic fields (I'm simplifying it a bit but this is how it goes) Because it's stiff plane of material between 2 magnets (hence the name planar) it vibrates across its entire surface area unlike a DD which is attached to casing that surround the dome and the magnet to which is it anchored. This is how planars are renowned for their speed and accuracy. They are precise. But they have less lateral movement than with a DD which is why you can have IEMs producing a similar frequency and even a similar quantity / quality of bass. The DD you will feel it because it's moving more air. The planar you will experience the precision and decay but you wont get the same visceral oomph of the volume of air. Timeless is the largest planar in my IEM stable and it has more bass slam than the others for that reason but it just doesn't move the same air as a DD.
I hope that makes sense and is helpful in some way.
