1430 hrs: E17 + E9 combo received, rather picked up from post office since parcel driver couldn't find my condo
1500 hrs: External USB charger used to fully charge E17 while I ran some errands
1930 hrs: E17 charge LED turned off - full charge took about 4.5 hrs
1945 hrs: After examining E17 menus/manual, attached DT770 Pro 250 ohm cans with volume set to 10 and started playing my usual suspects
2000 hrs: Macbook Pro set to output 96KHz, 24 bit over USB DAC - settled on volume of 40 with gain at 12dB for the majority of the tracks tested
2015 hrs: Changed my underwear, dried the tears and took some ibuprofen to ease the muscle pain from the perpetual smile on my face
Seriously - I LIKE IT!! Very similar sound stage compared to my Pico. Fiio obviously did a great job implementing the WM8740 DAC. I knew the DT770 250 ohm were hard to drive, and I was hoping for more power using the E17 by itself, but it still bests my Pico by a pretty decent margin. Trying it docked with the E9 was even more enjoyable. Now I had the power to really drive the DT770s well. Gain on the E17 has no effect when using "Line Out" or "Fixed mode (not LO Bypass). That did however change the sound signature of the E17 - I'm now using it on "LO Bypass" and taking advantage of the eq features of the E17. So far I've been able to produce a pretty accurate copy of the E17s signature, but with considerably more power left over to drive the DT770s. The gain on the back of the E9 is set to High - for use with high impedance/low sensitivity headphones like the 250 ohm DT770s.
I've got LOTS more playing to do, but so far, consider me very impressed. The E17 + E9 bundle is about half the cost of my Pico and really accomplishes everything the Pico gave me and more. Well done Fiio!
Dale