Twister6 has an extensive review of the ADEL A12 IEMs (custom and universal) over on Head-Fi.  This is probably the most complete review of these IEMs I have seen.

Summary:

Pros: driver coherency, resolution, spatial details, ADEL module, pair up with different sources.
Cons: additional cost of MAM tunable module, not for those craving revealing/analytical sound.

Review of the A12

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