In reviewing the Puritan Audio PSM 156 on ASR, the author says "as always, we attempt to tease out the transfer function of the conditioner using normal audio level signals" and after many measurements with test signals concludes with "as you see, I have run a number of tests to give the PSM156 ample opportunity to show it can do something to improve audio but it can’t even move the dial one hair. There is no indication or logic that would tell us that it can make an audible improvement."
It is important to note that at no point was it mentioned that music was played through a system with and without the PSM 156 in the circuit. I don’t spend my hours of relaxation listening to test signals - I listen to music. The ASR review failed to assess the impact on music reproduction. This is just pure nonsense - ignore them.
Imagine doing a wine review as follows - samples of 5 wines are given to a reviewer in a blinded fashion labeled A, B, C etc. The reviewer measures multiple variables including light transmission, specific gravity, residual sugar, salinity, and boiling point and determines the winner based on those measurements and concludes that the other wines can't possibly be as good based on their measurements. At no point does the reviewer assess the bouquet of the wine nor taste it. That is the ASR approach to audio - drinking Kool Aid, not wine.
The PSM 156, PS Audio PP12, and Accuphase PS-1250 all had a significant and positive effect on the sound of my audio system with blacker backgrounds, more detail and dynamics etc - as if a veil had been lifted between me and the music.