Tool
Impedance Synthesis
Digital synthetic impedance enables the design of systems where digital analog simulation co-exists flexibly with literal analog systems. It creates an arbitrary current for a given input voltage and can simulate any two-port electrical component. This system can replace a single component or a small network of components, including, for instance, a simple resistor, reactive elements such as inductors, and non-linear components such as a small diode network.
An approach to hybrid analog-digital audio processing using synthetic impedance: digitally simulated circuit elements integrated into an analog circuit. This approach combines the physicality and classic character of analog audio circuits alongside the precision and flexibility of digital signal processing (DSP). Our impedance synthesis system consists of a voltage-controlled current source and a microcontroller-based DSP system. It enables flexible co-existence and reciprocity between virtual analog simulations and literal analog systems.
Example applications include:
- Replacing individual obsolete components with digital facsimiles
- Configuring analog circuits on the fly
- Circuit bending and modifying existing circuits in the digital domain
- Exploring components that can’t be produced (theoretical/ideal)—e.g. Nullor circuits —within literal analog components.
Technical details may be found in the DAFx25 paper and companion repository.