A micromachined transducer array , comprising: a transducer substrate ; a plurality of transducers disposed over the transducer substrate ; and one or more switches (S1, S2, 372A, 372B, 372C, 372D, 601) disposed over the transducer substrate, wherein the one or more switches are electrically switchable between a first state and second state, the first state interconnecting at least two transducers of the plurality of transducers in electrical parallel with each other, and the second state interconnecting the at least two transducers in electrical series with each other, wherein the first state places all transducers of the plurality in parallel, and the second state places a first subset of the plurality in series with a second subset of the plurality, wherein the plurality of transducers comprise one channel of a multi-channeled array with each channel of the array including the same number of transducers, and each channel of the array switchable between the first state having all transducers of each channel in parallel and the second state having the first subset of each channel in series with the second subset of each channel, wherein the one or more switches comprise MEMS switches each associated with a respective channel of the array and wherein all of first MEMS switches are coupled to a single control signal line that is to concurrently set all channels of the array into the first or second state and wherein the MEMS switches comprise a piezoelectric, electrostatic or electromagnetic switching member, and wherein the plurality of transducers are resonant within an ultrasonic frequency band. a transducer substrate ; a plurality of transducers disposed over the transducer substrate ; and one or more switches (S1, S2, 372A, 372B, 372C, 372D, 601) disposed over the transducer substrate, wherein the one or more switches are electrically switchable between a first state and second state, the first state interconnecting at least two transducers of the plurality of transducers in electrical parallel with each other, and the second state interconnecting the at least two transducers in electrical series with each other, wherein the first state places all transducers of the plurality in parallel, and the second state places a first subset of the plurality in series with a second subset of the plurality, wherein the plurality of transducers comprise one channel of a multi-channeled array with each channel of the array including the same number of transducers, and each channel of the array switchable between the first state having all transducers of each channel in parallel and the second state having the first subset of each channel in series with the second subset of each channel, wherein the one or more switches comprise MEMS switches each associated with a respective channel of the array and wherein all of first MEMS switches are coupled to a single control signal line that is to concurrently set all channels of the array into the first or second state and wherein the MEMS switches comprise a piezoelectric, electrostatic or electromagnetic switching member, and wherein the plurality of transducers are resonant within an ultrasonic frequency band. <EOS>