I checked Garage1217's website, I am tempted...

This kinda worries me. It's a tube input stage and opamp output? Output buffers should be getting pretty hot at these currents.

Used to worry me as well, not any more though 
As stated ... no heat despite the max 0.23A current capability.
It even has thermal protection IN the output devices, should someone short the output.

One amplifier per room, good one.

Can a beginner build the kit by him or herself?

I received my Project Ember a few days ago and I've truly enjoyed it this weekend. I have very little experience with different amps (Maverick D1/A1, Schiit Magni, and Starving Student DIY) so the Ember was a definite upgrade, and very audibly so. I have been listening to my orthos off of the Magni and my dynamics off of the A1 for a few months and I was convinced that orthos were the right thing for me. The HE-400 and T50RP are driven very well out of the Magni and they are very detailed and free from distortion when compared to the DT880 or HD580 out of the A1 (I find the Magni to be too cold for my HD580's and especially for the DT880). I at first had this distortion contributed to the dynamics being, well... dynamics. I wasn't convinced that an amp upgrade would make a significant difference despite all the "scaling" I've heard about (especially with regards to the Senns). Needless to say, with the Ember, I'm astounded. Everything is executed so well and I'm finally listening to these dynamics for the first time. Complex passages are much more controlled and everything is much less congested in general. Though I don't notice a huge upgrade from the Magni with regards to my orthos, I wasn't really expecting to. The thing I notice the most about the Ember when compared to the A1 (with dynamics) is that when I increase volume, I'm actually increasing the volume of each instrument whereas the A1 sounds almost like I'm turning up the noise surrounding the instruments... truly an upgrade in my book! I now feel as though these other headphones are finally competing at the level of the HE-400.

 

Big thanks to Frans and Jeremy for such a great product! I still haven't even messed with the output resistance yet, so I've got some experimenting left to do...

Wow, that's a pretty big slam against the A1.  I just got one and really like the way it sounds.. I have the raytheon tubes.. haha and YET I already ordered a mjolnir that should arrive in a few days.  The A1 will be relegated to driving speakers only

I actually did some more A/B last weekend and I came to a conclusion: the majority of the distortion/noise I was commenting on is coming from the D1, not the A1. The D1 has two outputs, one that uses the D1 tube and one that bypasses it. I had the A1 plugged into the tube out (for whatever reason) during the initial impressions of the ember. I hadn't realized this until the thought occurred to me afterward, so I went ahead and A/Bed the outputs on the D1 with the Ember and with the A1. The D1 (undoubtedly) adds waaaaay more warmth using the tube pre out. I'm not even sure it's just warmth, because it doesn't sound particularly great. It is definitely the source of the noise I was having issues with before. So, I decided to start over with my original impressions of the Ember against the A1 and the A1 is definitely holding its own now. The Ember still surpasses the A1 in terms of resolution (using some random Russian tubes on the A1, I can't remember which) and overall body. To an untrained ear, you may not hear any difference at all though (I had a hard time picking up a difference before playing a 20 second passage over and over). Either way, the Ember is a great all in one amp. No longer will I reach for the A1 or the Magni depending on headphones because everything sounds great on the Ember.