With PSB and NAD being sister companies, I would start with any of the fine choices from NAD like the 375BEE/DAC or the 390DD. Both will come in under $2000.00.
http://nadelectronics.com/articles/NAD-Amplifiers-with-PerfectPitch
Bill
http://nadelectronics.com/articles/NAD-Amplifiers-with-PerfectPitch
Bill