Acoustics for Communications

Site Map
About and Contact

 

 

  Home 

Headsets - Earphones

Speakerphones

Audio Test & Audio Devices

Digital Telephones

Caller ID

Component Engineering & Other Services

Info and Links

 

 

Contact

Strip of Electroacoustic Pictures

 

* About Us

* Past Projects

* Test Equipment 

* Contributions to industry Standards

* Professional Memberships

Contact:

Ron Magnuson

Acoustics for Communications (AFC)

Austin, Texas USA

1-512-391-1531

 

About Us 

Acoustics for Communications’ specialty is evaluating product electroacoustics rather than the usual environmental noise/vibration/room acoustics work done by many acoustic consultants. We have the experience and specialized equipment needed to work with communications audio.  We have also work on many other devices such as iPOD® compatible headsets, intercom systems – even vacuum tube products.

 

If you have a new design that needs audio advice, a finished design that needs testing or a troubled project that needs bailing out please call.

 

Consultants – if you need specialized assistance with your project please call.

 

Owner, Ron Magnuson has been a consultant in electroacoustics since 2000. Prior experience includes 18 years as audio and component engineer for Siemens, IBM and Rolm where he developed and tested digital and analog telephones and speakerphones. He has done extensive work on headsets, hearing aid compatibility and has devised many unique speakerphone test methods that have become part of today’s handsfree standards.  He has been chair, editor, or significant contributor to many acoustic product standards published by ANSI/TIA and IEEE.    

 Back to Top

Past Projects include:

*   2.4 MHz Digital Cordless telephone Family

*   Hearing Aid Compatibility (HAC) – between telephones and hearing aids.

*   Digital Office Voice Terminals – numerous different designs.

*   Passenger Train Intercom Audio Evaluation

*   Voice over DSL – ADSL WIAD terminal.

*   ISDN and Proprietary Digital Terminals.

*   Cell phone car kit evaluation

*   Speakerphones (handsfree) – digital and analog.

*   Internet home security audio.

*   Handset – design of acoustic features to meet target frequency response.

*   Headset evaluation– evaluate headsets for compatibility with OEM telephones.

*   Assistive Hearing Device – evaluated microphone design, sensitivity and directivity

*   mp3 / iPOD®  headsets 

Past Component Engineering Projects include:

*   Loudspeaker – fixed buzz, rattle problem on production line and Far East.

*   Microphone– tests for qualification and receiving inspection.

*   Handset– production and receiving inspection tests.  Redesign with new elements.

*   Speakerphone– acoustic feedback, voice cutout, buzzing and assembly problems.

*   Capacitor evaluation  – saved manufacturer $300k yearly; reduced failure rate > 400%.

Back to Top

Test Equipment and Capability

AFC has an extensive array of test equipment from top vendors.

 

*   Bruel &Kjaer (B&K) Audio Analyzers

*   Head Acoustics and Sound Technology Audio / FFT analyzers

*   Bruel & Kjaer 4128 Head and Torso Simulator (HATS) with Handset positioner.

*   Bruel &Kjaer laboratory microphones (probe, free field, pressure).

*   Bruel &Kjaer Type 4227 Mouth simulators (artificial mouth)

*   All ear simulators used in communications standards (Except ITU-T P.57 - 3.4).

*   ITU-T Type 1, Type 2, Type 3.1, Type 3.2, Type 3.3 ear simulators

*   Wandle and Golterman PCM-4 to evaluate Mu-law, a-law based systems.

*   Rhode and Schwarz CMD55 GSM / PCS-1800/1900 Cell Phone analyzer

*   Advent and AST Caller-ID test systems.

*   HP impedance analyzer.

*   Etymotic Research human probe microphone.

*   Computer controlled turntable for loudspeaker and microphone polar measurements.

*   Philips and Tektronix oscilloscopes.

*   Other specialized test equipment – gauss meter, DAT recorders etc.

Back to Top

Contributions to Industry Standards

*   Chair of TIA working group that wrote VoIP, ISDN and wideband audio standards.  These standards are published as ANSI/TIA-810A and TIA-920.  

*   Contributor and member of working group for revised standard ANSI/TIA-810B.

*   Technical contributor or editor of IEEE standards for handsets, headsets and speakerphones.

*   Technical contributor to TIA standards on Caller-ID and telephony acoustic requirements.

*   Echo and Hearing Aid Compatibility investigations for the TIA. 

Professional Memberships:

*   Member IEEE – Active contributor to the Subcommittee for Telephone  Instrument
     Testing.

*   Member ASA – Acoustic Society of America.

*   Member AES – Audio Engineering Society. 

Contact:

Ron Magnuson

Acoustics for Communications

Austin, Texas USA

1-512-391-1531

 

Back to Top

 

 

acousticsFC.com

Back to Top          Site Map        Contact

© Ron Magnuson,
Acoustics for Communications

Austin, Texas