I spent about a week burning in the unit we got from Rhapsodio for review.
I really liked the way it looked, and the interconnect cable that came with it looks rather good (carbon inserts). I do have a picture...actually 3 of them, and none of them are in focus
. aaanyway - shane's got a pic above.
The amp is pretty small at 93mm * 58mm * 13mm (thinner and shorter than a cowon d2 and MUCH more portable vs JDS O2)
It also comes with an i-device interconnect, which I didn't get to use but some will find useful. (the LOD looked pretty plain and you might say it's not fancy enough
?)
I loved the gunmetal aluminum look...When you open the box it was probably the prettiest amp I've seen. Until I noticed some scratches on arrival (!). IDK, I probably wouldn't put the aluminum version in the pocket with keys or anything metal. That said - the overall build 'feel' (seemed very solid)
Like shotgun shane I noticed it had an imbalance at the lower end of the volume knob turn (I _think_ I could tell until about 11 o'clock (it starts at 8). The volume pot felt smooth and the gain switch had a nice tactile feel to it, so did all of the sockets.
On low gain - there's no background noise, on high gain it was silent on IEMs until volumes where my ears would melt... On high gain - I've also heard some sort of feedback on the line out from one of my DACs (might be DC offset on line out from the DAC messing with the amp?)
You can't charge it and listen to it - there's distortion and noise when it charges and if it has music playing. It lasted for about 48 +-5 hours for me when burning it in, but I wasn't really measuring it scientifically
and it was above listening volumes. (I suspect if you open it, there is a small SMD or discrete passive parts + opamp based circuit and a giant battery there)
Sound-wise similar to shotgunshane's initial impressions - it didn't have the firmest bass compared to Clip+ or O2, and it was a bit too bright for my liking. - Neither GMP450, not Rhapsodio 2v1, nor GMP435s suit it very well because of that. (aside from brightness it made the high impedance GMP450 sound grainy(?) in the mids...some sort of an odd quality i can't quite put my finger on. Maybe - enough voltage - not enough current as people like to say). Likewise, didn't really like it with my Sm3x8 (maybe PX-M1 has a relatively high output impedance - I'm not sure) - it for some reason made it sound a lot dimmer than O2 and the low end turned to mush.
I'm not a big fan when manufacturers don't quote the output impedance and then quote distortion and noise or power output separately (not x.xxx% at blah MW, but blah %, blah%, blah mw peak ouptput).
I think it matched T-PEOS H-200 well though. I found H-200 to be a bit dim on its own. (and that has enough firm bass to accomodate).
I think it might go well with something like HD650, but I'd be cautious of buying it for that prupose until some tries it. (besides those are open headphones - so portable amp - eeeh)
Finally, at $300 I think it's a bit too premium for me considering the above (yes, pretty, yes big battery - no I don't think the circuit inside is worth it, no I haven't opened it - the star screws on it are tiny and I don't have a tiny screwdriver
). I'd probably lean towards the beta22 mini cousin from AMB. or even O2 if not for portable use.