I cannot stop admiring those grains!
I thought I would share a few more thoughts on some further comparisons between the oak and my ebony Caldera. As stated earlier, the difference is not huge, but audible. I would class these differences as sub-variants of the same sound, probably marked with lower case letters 'a' and 'b' as opposed to 'A' and 'B' to further emphasise we are talking about minute differences. Keep this in mind.
When I put the oak pair on my head right after the black & white ebony, it sounds somewhat softer, less tight, slightly less clear. There is a slightly lesser sense of definition/weight/impact which also shows as a small apparent loss of soundstage depth, simply due to the marginally inferior clarity.
When I put the ebony pair back on my head, the sound immediately feels a bit speedier, more rounded, more focused, more dynamic but most of all: clearer. There is a bit more control, a bit more definition. The ebony pair somehow feels more solid and more rounded in its sonic presentation; oak sounds a little lighter and softer in comparison, but still not diffuse. This roundness is interesting, as with the 'clearer' sound I would expect a little more intense treble, but to my surprise that is not the case. Despite the small enhancement in clarity and definition, the edges of the notes are somehow more rounded, more coherent: the whole treble area feels a little smoother and more cohesive despite the slightly more impactful presentation. Bass is also a little more controlled and precise.
In my experience this coherence, cohesion and control is what makes TOTL headphones vs. 'mid-fi' category. With headphones that offer exemplary instrument separation like the Cladera, this coherent feeling of musical 'flow' is the hardest to achieve. This is why flagship headphones sound the most lifelike.
One last random thing I thought I mentioned is that I find guitar plucks on the Caldera truly exceptional. All acoustic instruments sound great on the ZMF flagship due to its weighty and organic sound, but string instruments somehow truly excel. From piano to violin everything sounds sublime, realistic and engaging, but guitar plucks particularly captured my attention the other day. (
Random example track.) Picking a guitar string creates a complex sound and it is notoriously difficult to replicate in a lifelike manner. (I used to play classical guitar in a previous life.)
One thing is to capture the lifelike, organic tone and timbre of the instrument. This is hard enough itself; I could probably count on one hand how many other headphones come close to the Caldera in this regard. The other thing comes down to technicalities: the speed of that guitar pluck, the attack, sustain and decay. Attack is so precise on the Caldera! Add the ability of reproducing a full dynamic range in a timely manner (usually more of a planar treat) and you have both sides of the coin: organic tone & timbre with speed, clarity and agility. What a combination!