Well, since this is a forum that likes numbers and since I am a curious bugger that can't leave things alone, I did some experiment.
Senpai
@amirm said that he was reluctant to torture the clear in order to find the values at which his loaned exemplar hit Xmax, and I can completely understand that. Being weary of damage myself, I thought about a way to make it happen anyway and this is the method I have come up with:
While listening, I slowly up the volume until the driver starts to exceed the designed travel and then I turned the volume back one notch (2% on the Windows 10 main volume). I measured that 10% corresponds to roughly 3dB.
I don't own a fancy headphone measurement rig, like Amir but I used the "UMIK through a CD-contraption" trick,
@solderdude gave me a while back.
So take these numbers with a hand barrow of NaCl. At least I think they should be usable ballpark figures.
No EQ of mine of any sort was applied to the actual music.
First test was the "Un espejo en el cielo" piece Amir linked earlier. The bass has it's peak at ~30Hz.
This is what I could get out of my Clear:
View attachment 103875
If I interpret the values correctly: 110dB (Z) weighted was the peak.
Next I used a 30Hz sine wave, created in Audacity:
View attachment 103876
Z weighted value seems comparable.
For fun I tried 20Hz:
View attachment 103877
103,9 dB (Z) of .... inaudible sound *shrugs*
My normal listening level peaks at around 90dB (Z), so for my purposes there is plenty of headroom left in the driver.
Now if s/o would be so kind and answer that darn telephone please!
Edit: now that my ears stopped ringing, I did the same test with my DT-880.
I got it up to 114dB (Z) during the music piece above but the bass was already distorting a bit.
With the Clear I get pristine sounding bass until:
BLÄM! Xmax.
With the DT-880 there is no hard limit but I get ever increasing distortion and it just sounds bad.
The workable range of the two is roughly the same. Now I realize that a DT-880 is a lot cheaper than a Clear. Would love s/o do a similar measurement with a different can that is comparable to the Clear but doesn't have that limit.