I remember you mentioned at the mini-meet that you thought these were rolled-off on the top. Looks like you were right.

I'm surprised to see them appear so smooth and well-balanced, although maybe I'm misinterpreting these measurements. Next to the ER4S, I felt they weren't as smooth. I thought the measurements might reveal some treble peaks TBH. I didn't have any problems with bass quantity FWIW.

If you'd like to demo/measure my ER4 after Anax, let me know. I think having plots for the Etys would be a very useful reference.

 

I don't think they were as smooth either, the 6-7khz peak seems to support that a bit.

Holy crap, that's a ton of roll-off... I'm trying to think of how that's possible, given what's used in the Noble 4.

I was also hoping to see more of the 2.5-3k mountain, but the mountain might be obscured by a big lower midrange lift that I know Noble likes to do.

The funky impedance is expected from BAs; single driver BAs usually exhibit an exponential curve impedance that starts really low and ends really high. Usually, the first resonance peak is induced artificially, so you'll see a weird sawtooth pattern to the impedance where the resonance peak is induced. When the drivers are joined together in a low/high configuration like the TWFK is for the midrange and tweeter portion here, the midrange is actually run in reverse polarity, which is why you see the impedance drop from the crossover point with the DTEC woofers, and then rise again for the tweeter portion. Running the midrange in reverse phase also helps avoid the upper midrange chasm that showed up earlier in the 4.Ai model.

My guess is that you'd like the Noble 4 better if they chose to use the vented DTEC (called the HODVTEC), which is unfortunately new and expensive. Currently, I only know of the UE900/900s using that dual woofer from Knowles. Drivers from Sonion are cheaper, but Noble seems to like to stick with Knowles. In some senses, Knowles is the technologically superior company. Their drivers exhibit lower distortion profiles, and their treble extends better, but their drivers are expensive (nearly 2x more than Sonion).

Even so, I would not have expected the Noble 4 to roll off this much. Maybe starting from 40 Hz, but not from 200 Hz. They'd have to add a cap to the woofer to do that (either that, or the driver is broken, but how can both sides be broken?) Did you check whether the coupling was secure and sealed?

On second examination, it's probably your tubing that exaggerates the roll-off, then. I suspect that under an expensive ear simulator, the Philips and JVC would have upward rising bass (usually the case for consumer-grade earphones), while the Noble has some minor roll-off, as well as a small mid-bass hump (even though people are saying it has no bass, surely it has some, because relative to the midrange, the entire shelf is elevated).

The ER4 would probably resemble the Philips curve, except from 800 on down, it'll keep sliding down to 20 Hz.

Yeah, certainly with compensation, it'll look a lot more relatable, though I've been trying to translate these measurements to raw ear simulator measurements.

Yes the Noble 4 uni has a small mid bass lift compared to the ER-4S, then it starts to roll off in deep bass similarly to the ety. I also heard a large 6.5k peak in the Noble. It was large enough to affect timbre and be an annoyance. The ER-4S was much smoother overall.