Bear with me a minute here... I currently have an Echobox Explorer. Which looks great, sounds wonderful, and has a pretty darn decent amp, but...the wifi is terrible, and the battery life so poor that I can use it for an hour or two if I'm Lucky. In other words: useless. So I'm after an upgrade. I mostly listen on the go, sometimes with bigger cans (HD6XX, HE4XX, Meze 99 classics), sometimes IEMs (usually Shure SE535s, though I'm eyeing an Andromeda), sometimes wireless (Advanced Audio model 3 bluetooth cable with the Shures, or Sony noise cancelling when traveling, or the bigger cans via a Bluewave GET, because its more powerful than the iPhone's amp). Most of my listening is via my iPhone 6s Plus, using Tidal or Apple Music. I have a fairly large collection of lossless files as well, but they don't really get listened to much at the moment. Basically, I want something that will provide a better experience, and will drive the bigger headphones at least decently. I am not willing to carry around a stack of stuff while on the road. The A&K SR15 is at the top end of what I want to spend; on paper, it looks like a good bet - smooth OS, good amount of power, future MQA support likely, Tidal offline. The Fiio M9 is attractive because of its cost (low) and feature set (particularly bluetooth connectivity) and size, but has a fairly underpowered processor. I'm wondering whether waiting for the rumoured M11 may or may not be worth it. I'm a little loathe to go with an X7 due to reports of so-so software reliability and battery life with the amp cards I'd likely want, plus it takes me out of my desired price range. That brings me to the more 'out there' option of either an xDSD or an xCAN; both are svelte enough to stick in a coat pocket and can be used as wireless bluetooth receivers, or plugged in at home as compact headamps that should be able to drive the bigger cans without too much ado. The former is of course a DAC with a pretty powerful headphone amp circuit, but the latter has a much more powerful amp, and I wonder whether that's not the better choice. Thoughts?