# Why Sound Processing Takes Time, Not Just Frequency

- Show: [EE Times Current](https://hardwarepodcasts.com/podcast/ee-times-current)
- Published: 2024-03-15
- Length: 45m
- Page: https://hardwarepodcasts.com/podcast/ee-times-current/2024-03-15-why-sound-processing-takes-time-not-just-frequency
- Listen: https://podcast.show/aspencore/episode/131511897/

## Summary

Dr. Shih-Chii Liu, co-director of the Sensors Group at the Institute of Neuroinformatics (ETH Zurich), explains how her neuromorphic silicon cochlea converts sound into asynchronous spikes to enable low-power voice activity detection. She details the use of delta modulation for faithful signal representation and 'delta networks' that leverage activation sparsity to reduce energy consumption by over 50%. Professor Ralph Etienne-Cummings of Johns Hopkins University discusses the historical context of silicon cochleas, citing early work by Carver Mead and Andre van Schaik, and their commercial applications in hearing aids and sound localization.

## Chapters

- [0:02](https://hardwarepodcasts.com/podcast/ee-times-current/2024-03-15-why-sound-processing-takes-time-not-just-frequency#t=2) Introduction: Dr. Shih-Chii Liu and Neuromorphic Engineering
- [3:36](https://hardwarepodcasts.com/podcast/ee-times-current/2024-03-15-why-sound-processing-takes-time-not-just-frequency#t=216) Silicon Cochlea and Spiking Interfaces for Audio
- [8:06](https://hardwarepodcasts.com/podcast/ee-times-current/2024-03-15-why-sound-processing-takes-time-not-just-frequency#t=486) Delta Modulation vs. Integrating Fire Models
- [10:48](https://hardwarepodcasts.com/podcast/ee-times-current/2024-03-15-why-sound-processing-takes-time-not-just-frequency#t=648) Delta Networks and Activation Sparsity
- [15:16](https://hardwarepodcasts.com/podcast/ee-times-current/2024-03-15-why-sound-processing-takes-time-not-just-frequency#t=916) Evolution of the Field: Biology to Computer Science
- [24:25](https://hardwarepodcasts.com/podcast/ee-times-current/2024-03-15-why-sound-processing-takes-time-not-just-frequency#t=1465) Historical Context: Mead, Van Schaik, and Commercial Applications
- [36:55](https://hardwarepodcasts.com/podcast/ee-times-current/2024-03-15-why-sound-processing-takes-time-not-just-frequency#t=2215) Delta Networks for Multi-Sensory Fusion and Efficiency

## Topics

- [Analog & power electronics](https://hardwarepodcasts.com/topic/analog-and-power-electronics)
- [Embedded firmware](https://hardwarepodcasts.com/topic/embedded-firmware)
- [Chips, FPGAs & semiconductors](https://hardwarepodcasts.com/topic/chips-and-fpgas)
- [AI & machine learning](https://hardwarepodcasts.com/topic/ai-and-machine-learning)
- [Sensors & measurement in products](https://hardwarepodcasts.com/topic/sensors)

## Most relevant to

early-stage companies

## Mentioned

- Institute of Neuroinformatics (company)
- ETH Zurich (company)
- Johns Hopkins University (company)
- Fortiss (company)
- Caltech (company)
- Carver Mead (other)
- Andrei van Schaik (other)
- Gerd Schindler (other)
- Chris Tomasi (other)
- Andreas Andreu (other)
- DARPA (company)
- ASU (product)
- Paul Mueller (other)

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- [Episode 139: Advanced robot hearing - Christine Evers](https://hardwarepodcasts.com/podcast/robot-talk/2026-01-09-episode-139-advanced-robot-hearing-christine-evers) (Robot Talk)
- [Ep 314: It's Pi, but Also PCBs in Living Color and Ultrasonic Everything](https://hardwarepodcasts.com/podcast/hackaday-podcast/2025-03-28-ep-314-its-pi-but-also-pcbs-in-living-color-and-ultrasonic-everything) (Hackaday Podcast)
- [Silego, ADCs & Seismic Detection - Dave's Dingo Dystocia](https://hardwarepodcasts.com/podcast/the-amp-hour/2011-10-18-silego-adcs-seismic-detection-daves-dingo-dystocia) (The Amp Hour)
- [507: Turn Our Data Into Predators](https://hardwarepodcasts.com/podcast/embedded-fm/2025-08-07-507-turn-our-data-into-predators) (Embedded.fm)

## Citing this page

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