I can't address your speakers, but I recently upgraded from a 340i to a 740P + 760A (one), and the difference in noise floor was dramatic, and strangely enough, the external phono stage has much less incoming noise on the 740P vs. the 340i (using the same input type on both). If anything, the 740P makes the 340i seem like a much worse choice at its price given how much better the 740P sounds in my system.