I brought this headphone amp after reading many different reviews and after having a good experience with a cheaper valve amp (Bravo Audio Ocean) and dissapointments with solid state amps up to $350US.
 
The Amp straight out of the box sounded quite bright with my Audio Technica ATH-A700 and ATH -AD700 and Beyerdynamics BT880 (600 ohm) but within a few hours of burn in  it had started to give that smoother tube sound that I prefer.
 
I am not running any top end equipment through this as I sold all my HIFI gear a few years ago when the kids arrived. I am currently just running a cowon S9 and J3 through the unit with MP3 files (320 bit rate) and Flac files direct from headphone output as these players do not have line out. I also have my muscial fidelity A3 CD player hooked up on occasion which is the last of my hi fi days but find the limitation of one CD not worth the effort for the increase in sound quality.
 
I mainly listen to blues, blues rock and acoustic music and while I have read numerous threads and opinions regarding the value of doing this type of set up and the many views this is a waste of time - all I can say is that from my perspective the sound experience through the amp vs direct from the cowon is completely different (cowon on the BT880 is very low volume due to impedance) and worth every cent
 
The other fun bit is the ability to tube roll on the little dot - have not done this yet but had some fun with by Bravo Audio Ocean changing things around.
 
The only thing I have found a bit different is that the volume level needs to be at 3 oclock for normal sound volume on high impedance headphones - not that this is a problem - full volume is cystal clear and louder than i would ever use. Compare this to my Bravo Audio ocean and the volume does not get past 12 oclock
 
After many hours of listening I have come to the conclusion this little dot amp loves the high impedance headphones and the Bravo audio ocean loves anything you throw at it.
 
I have had many Cmoy headphone amps and larger solid state amps and my only 2 tube ones beat all the rest hands down.
 
Thanks to all the reviews comments and advice people have on these forums as they all give you somthing to agree or disagree with or advice - at the end of the day its what each of us personally think that counts - for me this is a winner amp at a value price ( so is the Bravo Audio Ocean if you can't afford the little dot)
 

I was searching for a budget tube headphone amp and this one caught my eye just because of the colour and shape. There was very little in the way of reviews for this I could find other than a utube clip.
Having had Cmoy type amps and a few solid state amps in the $100-$200 running off a cowon S9 with various audio technica and sennheiser headphones I could not  get the sound i was looking for.
Took a risk and brought this little amp and I am very glad i did.
In my view this made my ATH-a700 and ATH-M50s sound significantly better than being driven straight from source.
The bass and sound stage depth appeared much better and i found myself listening and getting more involved in the music for hours at a time.
I think this is a great value amp which has a very rich and smooth tube sound- at this price you should not be dissapointed