Which is the least affected by RFI: the Linto, Uphorik, Urika or Superline ?? Does anyone have experience they could pass on ?
My experience of the Superline (my first MC phonostage) is that it is prone to excessive RFI which is a really disappointing aspect of it's performance.
Yes, the Superline IS prone to RFI, for one very good reason; that it is (like Naim stages before it) of wide bandwidth design.
The Prefix K (= wider bandwidth than S) before it was NOT particularly prone. I put that down to having no nasty arm-lead picking up the RFI. I had problems on cards before the Prefix; none afterward.
RFI is a changeable beast; it varies randomly and seasonally and can be influenced/exacerbated by earthing arrangements/faults.
My Superline is quite well behaved, though it can have its moments by 'dumping' its RFI build-up though the speakers; this is infrequent, though, and can be tamed by increased capacitance. Unfortunately, increased capacitance usually equals a less dynamic sound. Luckily, there is a happy medium which addresses both circumstances.
Given the choice of a 'safe' phono stage which has RFI filtering in its design and something like the Superline which gives it to you warts and all, there is no contest for me. Adding Supercap and Burndy was, if anything, a positive step in RFI rejection, odd as it may seem. A no-brainer in sound quality terms, though.
SQ thinks the Urika may suffer c.f. the Superline, but if its design philosophy is similar to that of the Prefix (which I believe is the case), I'd say the elimination of the arm-lead puts it ahead in terms of RFI rejection; also, theoretically in sound quality, all things being equal, which they never are, of course.
I had a very well regarded £3k LFD stage for a few weeks after the Prefix and discovered that Belgium was an exciting place (apologies to continental PFMers). Each to his own. I've found that 'different' is more common than 'better' and received wisdom is helpful, but the only true yardstick is to live with something within your own system and environment.