For MEMS microphone testing, Audio Precision now offers the PDM I/O option that allows its APx500 series audio analyzers to connect directly to devices with a PDM input or output. Plus standard audio measurements, the APx PDM Interface provides variable DC voltages, variable sample rates, and a power supply rejection measurement function. Mono or stereo PDM is selectable for analyzer inputs and outputs simultaneously and a PDM bitstream mode permits analysis of the entire spectrum prior to decimation stages. Pricing for the PDM option is $4,500, the same as the upgrade price for existing instruments until December when it moves to $5,500. AUDIO PRECISION INC., Beaverton, OR. (800) 231-7350.