Just received my A4 - initial fleeting impressions, better fit than A3/S and 'more' - more of everything good that went before in lower models/more technically proficient. Seems a tad cooler tonality than A3/S but that may be down to my current 'dial'.
Using black back plate just now and dialing nozzles. Quite a bundle you get in the box.
It even sounds pretty darn good straight out my Macbook Air cirrus DAC/amp with Audirvana Plus and FLAC...I'll be escalating through my small equipment stack to find the sweetspot of dialing options.
Will be spending a week or so with them travelling before posting a review. I received my set free for taking part in the prototype tour but regardless, I'll tell it how it IMO is.
Been a fanboy anyway since I first put the A2 hybrids in my ears....no brain burn-in/hardware burn-in, just an instant WOW for the price at that time.