I have an Aries Mini. I bought an IFi 15 volt power supply shortly after purchasing the Mini. The improvements in the sound of the Mini were amazing with the IFi PS. Bass presence/ response in the 50 - 100 Hz octave increased dramatically. Overall, imaging and placement became much wider, deeper, and more precise. Placement of individual instruments In 3-D space became much more clearly defined. The characteristic sound and tonality is precise and accurate; neither overly warm nor “clinical.” These sonic improvements are not subtle.
The $50 investment in the IFi is a no- brainer, in my experience. Auralic themselves make a $300 LPS. It may be even better than the IFi, though I have not heard it. I think a lot of the sonic potential of the Mini is obscured by the stock wall wart.