An apparatus, according to one embodiment, includes a plurality of first circuits, each first circuit comprising a pair of terminals coupled to a first read transducer and a first parallel circuit. A terminal resistance of each first circuit is less than the resistance of the first read transducer thereof. A second circuit has a pair of terminals that are coupled to a second read transducer having a tunnel valve structure. An area of a tunnel barrier portion of the second read transducer is larger than an area of a tunnel barrier portion of each of the first read transducers. A resistivity of a tunnel barrier of each of the first read transducers is about the same as a resistivity of a tunnel barrier layer of the second read transducer. The terminal resistance of each first circuit is less than about five times a terminal resistance of the second circuit.