Tom Miller, Sr. Principal Engineer, Knowles Electronics
Location: Zoom Meeting (Virtual; See description for details)
Speaker(s): Tom Miller, Senior Principal Engineer, Knowles Electronics
Note that this meeting will be limited to 100 participants.
POST-MEETING UPDATE: A recording of the presentation is now available at
A NOTE ON OUR NEW FORMAT:
As you may have noticed, this month's meeting is a bit of a departure from our normal mode of operation. Even though Governor Pritzker has extended the “stay-at-home” order for Illinois until April 30, the Chicago AES Section is indomitable, and will continue our meetings online!
We will be hosting this meeting using Zoom. The one drawback we are facing is that participation is limited to 100 people. We plan to have a recording of the meeting available online afterwards, however. Please be sure that Zoom is installed on your preferred device prior to the meeting time (app store for iOS/Android, or the meeting link should prompt you to install the app on Mac or PC). You can either use the audio on your device, or call in for the audio with these instructions
The meeting will be introduced and moderated by Andrew Bellavia (Director of Market Development, Knowles Electronics). Most participants will have audio and video muted during the meeting. The moderator will un-mute participants in turn to ask a question during the Q&A period. This will be explained again at the beginning of the meeting.
Many companies wish to add Active Noise Control (ANC) to their wireless music headsets. ANC makes wearing insert earphones more pleasant, and makes the music easier to hear clearly. Unfortunately, most publications on noise cancelling lack practical information needed to make many key design decisions, and the experts are quite reluctant to share their methods. This presentation will help fill some of those gaps, covering many of the factors needed to provide good noise reduction in small headsets. It will cover the basics of ANC operation, then go onto discuss design factors such as headset acoustics and venting, filter design, and transducer selection. Tom will discuss how to keep an ANC system stable across a variety of wearers, dispelling some myths about latency and stability. He will show how to make good use of balanced armature devices in ANC systems, including how to add a tweeter without disrupting stability. The discussion will conclude with a brief description of transparent pass-through operation and some more advanced ANC techniques that adapt the headset to users and certain use cases.
ABOUT THE PRESENTER:
Tom Miller is a Senior Principal Engineer at Knowles Electronics, and has been there for nearly a quarter century. Over those years he has helped to create many of Knowles’ balanced armature receiver designs and has been granted over a dozen patents. More recently he has been studying how Knowles microphones and receivers affect system level issues, such as the control of wind noise pickup and active noise cancellation. Tom is a former Regional Vice President of the AES, and has held every local office except treasurer. Back in a previous century Tom obtained a Bachelor’s degree in Electrical Engineering from the University of Michigan. Upon graduation, he worked for a dozen years as chief technical engineer of Universal Recording, a major Chicago recording studio in its day. After that, he spent a few years working on signal processing for loudspeakers at International Jensen before moving on to Knowles. In his spare time he creates electronic music under the name Shadreaux, having released several albums on Bandcamp (but selling almost none).
Other Business: From AES HQ: AES Helps "Socially Distancing" Members Worldwide Listen, Learn, and Connect with Discounted Membership Rate Extended Through April 30. To help audio professionals stay connected as the world enters a period of isolation, the Audio Engineering Society is offering 3-month membership for $25, or a 3-month bonus at the standard yearly rate, through April 30, for both new and renewing members. Enrolled audio students receive an even bigger discount with AES Student Memberships starting at just $10 – find out more here.
Posted: Tuesday, April 7, 2020