Thank you Michael, Joule-Electra has an excellent reputation and the matching with Spectron comes highly recommended by Simon Thacher. I experienced a similar performance leap migrating from Capri to the Rowland Criterion reference pre for feeding the Rowland 312. It is probably an issue of consistent voicing across the product line, as much as it is the degree of isolation of the power supply, the type of transformer coupling of inputs and outputs that pretty well avoids any impedance mismatch, and I could go on waxing poetic on technical detail. . . . Lots of paths to Nirvana, isn't it? G.