Looking for an amp that measures well and can power DT880's 600 ohm

I'm looking at a possible amp upgrade soon, but it's nearly impossible to wade through what's out there nowadays. Reviews seem to be mostly pictures of the box the thing came in or fluffy adjectives that don't really tell me anything.

Can you guys help me? My headphones are Beyer DT880s 600 ohm. I'm looking for an amp, solid state, that can drive them. I want an amp that measures well (I'd prefer some real RMAA numbers) and delivers a transparent, uncolored sound. Right now I'm using a Darkvoice 336i. It sounds good, but I want to see if I can find something at a reasonable price that is less colored and can maybe drive the headphones better. Some older CD's require me to turn up the amp to 3 o'clock to get to a reasonable volume.

I'm also going to buy a USB DAC, but I've pretty much settled on the Music Streamer II.

"Reasonable price" is a moveable feast, but "solid state, measures well, transparent and uncolored" makes me think of current modern-era German stuff, like Violectric, SPL, or Meier.  Those guys are all solid engineers and their basic competence is unquestioned (much rarer than you'd think!)  There are those who say the Violectric 200 is a little warm, but it's based on a famous 1970s Nakamichi circuit, and the others in their range are less boutique, and they can be fitted with excellent USB DACs for a good one-box solution.  I had the DT880s for five years and would say that any of those new German amps would be ideal for what you seem to want.