I wasn't able to get my hands on the amp until last Tuesday due to being away for the Columbus Day weekend. Finally FedEx left the package and I've been using the amp ever since. I'll do a more in depth review once I've spent more time with the amp, especially comparing it directly to the Larocco PRII, which is the best portable amp I've heard.
Overall, I really enjoy the sound of this amp. I've hooked it up with an iHP120HeadRoom Overture DAC, and Proline 750s for a ridiculoulsly clumsy portable unit (OK, I only walked around my house with it). Wow! what head-thumping bass mixed with incredible detail. This was a good combo, although I didn't spend a lot of time listening to this set up.
Primarily I've been using the amp with the iHP120 playing various types of compressed files, albeit lightly compressed, and my UM2s. I find the UM2s to be a bit on the warm side, with smooth mids, and perhaps a tad bit rolled off. I would say that with the Millett Hybrid Portable, I'm getting more of the same but perhaps the dynamics are bit more evened out. Highs are still not sparkly but certainly present and the overall sound is very musical, indeed. The amp also provides very decent imaging and soundstage. The other day as I was getting off the train I had to turn around because I thought someone behind me was talking to me, but it was a background vocal track. I love the UM2s for their comfort and this amp may possibly make them all the more musical as well.
I do have a couple of problems with the amp but not related to sound. I find the volume knob can get moved easily. Also, the microphonics are quite pronounced. If you touch the amp at all it makes a noise like someone is ringing a bicycle bell. It is extremely important that if you use this amp portably, that you minimize any movement. I've managed to tame the probelm by putting it inside a HeadRoom Traveler bag and then sticking that inside my laptop bag. One other issue, which I'm not sure if it is a defect or just the nature of the amp, but it seems to be prone to "interference" for lack of a better term. I get some static from time to time and I can't really figure out where it's coming from. I've tried different ICs but that doesn't seem to eliminate the problem. It does seem to be aggravated by moving the amp but it is not a cause and effect relationship, like the "bell ringing" issue.
This week I'm going to plug the amp into my main setup using the Ack dAck. That should be a nice test of how good this amp really is. I suspect it is going to scale nicely with the increase in source quality.
