FWIW, the Lamm LL2 Deluxe has one set of "Direct" inputs that bypasses the tape loop and another selector switch, and therefore provides the purest signal of all the available inputs.
This would seem to satisfy your desire for signal purity for one source, yet provide some flexibility for more sources down the road.
This would seem to satisfy your desire for signal purity for one source, yet provide some flexibility for more sources down the road.

