The differences are small but its brighter than I expected based on what the AKM DACs were described as and in direct comparison to my old ESS based one. Not really an issue as its got the built-in peq and its probably exacerbated by the hifiman headphones.
Understood. I suspect it's not the end of the world for my setup, particularly how I would be using with a Tube setup for music. That said I would like to see some more reviews come through on the K15 (and the K13 R2R). But some of these audio products don't exactly have co-ordinated releases when it comes to the slow drip of reviews for certain products.