@kijanki Benchmark reduced noise by 10dB by switching from linear power supply in DAC1 to SMPS in DAC2 and DAC3. SMPS ... can be wonderful if done right. My Benchmark AHB2 has SMPS and is very quiet.
PS Audio gear is switching to SMPS as well, according to Mr. Paul McGowan. Both the iFi iPower X and iPower 2 are SMPS with 1 microvolt (µV) ripple noise, while audiophile grade LPS typically has noise levels in a range of 25-100 µV. Technology advances, folks, just like class D.