A universal measurement device for dynamic measurements can be found with the PXI-5922 flexible-resolution digitizer. It's part of the National Instruments modular instruments series. Used with NI LabView 7.1, it can function as an ac voltmeter, audio analyzer, frequency counter, spectrum analyzer, or I/Q analyzer.
Key to the PXI-based device is the NI FlexII analog-to-digital converter (ADC), which can sample anywhere from 16 bits at 15 Msamples/s to 24 bits at 500 ksamples/s. The ADC uses patented techniques that reduce the linearity and temperature drift errors inherent in multibit sigma-delta converters. What results is a high dynamic range at high sample rates. Combined with low noise levels, these rates let engineers directly digitize low-level signals without the need for external signal-conditioning devices, like filters and low-noise amplifiers. Removing the signal conditioning improves measurement accuracy and reliability while cutting test system development time.
Prices for the PXI-5922 flexible-resolution digitizer start at $6495.