This amp has been a learning experience for me. Honestly, I did not care for it much when I first got it. It has more power than I will ever use and it is very accurate. I am not usually a fan of flat and neutral, but this amp has been winning me over.
A few days ago I got a set of new (demo's) headphones, the Fostex TH-610. I figured I would try the Fostex on this amp because it would reveal their true sound. I am Very impressed with these headphones. Never have I heard drumming so prominent. Really out front on rock, but even with jazz, Florence and the Machine and Steely Dan. Definitely a new sound for me and very enjoyable.
The reason I am writing this is that I was looking forward to trying these out on my Liquid Spark. I did, for about one minute. With the Spark, the fullness was missing as was the bass. I figured maybe it was just a power difference since I hadn't volume matched the amps and so I cranked up the volume. It got much louder, but could not compete on sound quality. I get there is a large difference in price, but I have been super impressed with the LS against all my other amps, including this one. Until now. Weird.
Also, I recently bought a used pair of HD58X's and have been very impressed with their value (Yes, I have been bargain hunting the last few months). After several days of playing them in various amps, I put my 610's on and it was a night and day difference. I have never gone from an open back to a closed back and been blown away. The clarity, the bass, the full sound was Amazing! The next day I came back down to earth and realized the 610's are Not the clearest headphones ever made.
The last few days really have been eye opening though. And yes, I Really do like my SP200 right now.
Shane D