under 200

I'm looking for the best value power amplifiers, new or used, under $400. Though, I would prefer under $200 if there's something significant. So far, I haven't found anything with both power and SINAD comparable to the Niles SI-275.

Hello, I am new and have Marshall Major 2, now I am thinking upgrading my headphone set. So for 200 euros approx, I am between Sony MDR-1AM2, Audio Technica M70x, but general I want to be slim, (like the sony) close type with little boosted bass and flat mid-high frequencies. On Sony I read they...