The use of capacitors in an audio signal chain is often fraught with mysticism and little quantitative analysis to justify capacitor selection. With many capacitors costing more than the integrated circuits they serve, it is a challenge to determine a solution that balances cost, size and performance.
This article offers a brief overview of capacitor technology and compares the use of various capacitors in a real-world audio application. The capacitors in this comparison are configured to AC-couple the inputs of a precision audio data converter. Analysis of the data converter output provides an easy way to compare capacitor contributions to signal-path distortion. The goal is to help you make informed decisions about capacitor selection in audio signal-chain applications.