russ andrews psu for nd-s1Having had this for several weeks and having run it in over many hours, i have compared it to the original stock psu.
Equipment used for the comparison:
Ipod 160gb 7g, optical (ixos) cable from nd-s1 to dacmagic and then to Stax sr303 plus energiser (van den hul cables).
The difference are (to me) marked, there is a less brash, more delicate sound with more detail and space (you may obtain less noticable results with less revealing headphones) - altogether a worthwhile if expensive item and one i did try to source a cheaper upgrade psu in the UK without success.
Given Russ Andrews gives a 60 day return policy it makes sense for anyone to try it and while i expected to send it back having read the comments about the cost etc. of the russ andrews psu replacements, i shall actually be keeping it, still cheaper than the stock wadia.