Just cracked open another pair of Mikros 90 last night.
Right now I have three (3) stock pairs up-and-running, and no two of them sound the same.
(1) [bhazard] Stock Pair #1: warm-sounding, slightly bass heavy, fit is very poor [feel like they will flip off my ears],
(2) [opened winter] Stock Pair #2: lean/bright-sounding, detailed treble, bass light, fit is excellent,
(3) [opened spring] Stock Pair #3: great balance--the best I have heard stock so-far, very airy soundstage, super bass reach, definition and presence, fit is excellent.
Stock Pair #3 are not fully broken in yet, but sound very, very promising. They sound really good already, with less than 20 hours. Treble is a bit sharp, and mids a bit hard, but they should settle down over extended break-in.
Now I can better understand the mixed reactions that the Mikros 90 have elicited from many Head-Fiers. If "Stock Pair #2" were the only MLs I had ever heard, I would have been disappointed in general and less apt to hype the Mikros 90 the way I did. If, on the other hand, "Stock Pair #3" were the only MLs I had ever heard, I would have hyped them even more than I originally did. [Note: The very first pair of Mikros 90 that I heard [November 2013]--and hyped--were subsequently modded and became my current favorite SPACEY/BASSY pair.]
Well, I cannot [as easily] imagine that the drivers themselves could be THAT different from each other between the three pairs. My best guess is that variation in the permeable membrane patch that covers the Rabbit Hole contributes mostly to the Mikros 90s' sonic variability.
With Stock Pair #2, I might try systematically poking very small [surgical needle-sized, as someone earlier suggested] holes in that membrane and listening for changes. Or I would sell that pair with a proviso that modding was a "must".
I am on the verge of getting the Oppo PM-1. The Mikros 90 need another "worthy contender".
Edited by pataburd - 6/4/14 at 11:47am