Quote:
Originally Posted by
sepinho 
I suggest you try your sflo2/UM3X combo before you decide to get an amp. The sflo's headphone out is pretty darn powerful and the player has really good bass as-is. I have yet to use an amp with my sflo, because I don't see the need for one. Granted, mine are a little more lo-fi.
I've lately been using the rather demanding Sunrise AS-Charm with the the sflo a lot and it works just fine unamped.
I second this - The Nationite sflo2 or Teclast T51 has enough power to drive HD650 - at full volume it is just a little too loud for me, but its drives these 300 Ohms with a fairly dry sound, not much dynamics. When I use my Blox TM5, I cannot go anywhere near full volume and the dynamics are much much better. Sound was always crystal clear either way.
If you enable the EQ, you won't lose much quality, maybe 10db off the current S/N ration of 115! you will lose power though and driving say HD650 will not be loud enough, however HD650 hardly needs any EQ.
I was faced with the same decision and decided to buy a desktop amp instead of a portable amp to go with this device.