----- Experience in your own room the magical nature of stereo sound -----



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       About me ...
From the cover of The Audio Adventure magazine, February 1996.
Read the whole article here.


  • When Jan Didden visited in October 2010 he interviewed me about my involvement with audio before, during and after my 37 year career in R&D of Microwave and RF Test Equipment at Hewlett Packard Co. (now Agilent) in California. The interview was published in the Juli 2011 issue of AudioXpress magazine.

  • At AXPONA-Atlanta in 2011 I was interviewed by vimeo about ORION-4.

  • At the ALMA International Winter Symposium in 2014 I was honored with "The Titanium Driver Award", which recognizes a specific technical contribution, accomplishment, or expertise in the loudspeaker industry. The award was presented by Laurie Fincham (KEF, Harman Group, THX). I had written a letter to him in 1974 with questions about loudspeaker design at KEF and explained what we had observed at HP in our DIY loudspeaker design efforts. An extensive air mail correspondence, personal meetings and a lifelong friendship followed.

  • At the REPRODUCED SOUND 2015 Conference of the Institute of Acoustics in the UK I received the "Peter Barnett Memorial Award"; "For technical excellence, practical advancement and education in the fields of electro-acoustics and speech intelligibility" -. Photos & Sound

  • The UK audio magazine Hi-Fi News & Record Review reports on me and my work for rendering sound scenes in their March 2016 issue:
    hfn-cover.jpg (151954 bytes) hfn-page1.jpg (382556 bytes) hfn-page2.jpg (394450 bytes) hfn-page3.jpg (412955 bytes) hfn-page4.jpg (413150 bytes)

A little bit about work, fun and life ...

Work / Fun Hewlett-Packard Co., Palo Alto and Santa Rosa, California, '61-'98
(R&D Design Engineer, Project Mgr., Section Mgr., Senior Engineer)
Siemens, Zentrallabor, Muenchen, Germany, '61
Telefunken, Hannover, Germany, '57 
Major Projects / Designs 8566 Microwave Spectrum Analyzer, 100Hz - 22GHz, '78
8554 RF Spectrum Analyzer
8405 RF Vector Voltmeter
8546 EMC Analyzer
85650 Quasi-Peak Adapter
85685 RF Preselector
EMC Standards Development ANSI C63.1 
IEC/CISPR SC/A, Publication 16
Education Ongoing ...
Stanford University, EE, '62-'64
TH Darmstadt, Germany, Dipl. Ing. Elektrotechnik, '55-'61
Abitur, Kant Gymnasium, Bad Oeynhausen, '55
Radio Amateur License DJ1SX (diy 2-m rig), '51
Audio Fun / Work Linkwitz Lab, consulting/sharing, '99-present
Phoenix  3/2000 *** Thor  7/2001 *** Orion  9/2002 *** Pluto  4/2005 *** Pluto+ 7/2006 *** Orion++ 1/2007 *** Pluto2  5/2008 *** Orion3  7/2010 *** Orion4  4/2011 *** LX521  10/2012 *** LXmini  6/2014 ***  LXstudio  5/2015 ***  LX521.4  6/2015  ***  LXmini+2  4/2016  *** LX521.5-ASP  6/2016  ***  ASP.4  12/2016  ***
Audio Artistry, VP of Engineering, '94-'99
(Vivaldi, Dvorak, Beethoven, - Elite, - Grand Loudspeaker Systems)
G-Jobs with colleagues at Hewlett-Packard, '62-'94
(FM tuners, stereo decoders, pre- and power amplifiers, equalization of commercial speakers & headphones, passive crossover box speakers, active crossover box and open baffle speakers)
Fun Reading, digital photography, listening to recorded music, live music, audio design, recording, traveling, windsurfing, downhill skiing, hiking,    
Home front Born '35, Bad Oeynhausen, Germany
Father: Oeffentlich bestellter Vermessungsingenieur (surveyor); Mother: School teacher's daughter; Brother: 8 years older
WW2 and post-war Germany from a young person's perspective, '39-'48
Lutheran Confirmation (but serious doubts about religion), '49 
Married, '61 (my wife's assessment of a loudspeaker's sound and appearance is important to me)  
Working at HP in California for a 2 year cultural experience, '61
Involvement with New Age groups ('63+) and challenging R&D work at HP resulted in permanent stay in the US  
Daughter in '62; Son in '65; Granddaughters, '99, '04, '05
Spiritual search  Jesus as Teacher discussion groups - Sequoia Seminar - LSD - Creative Initiative - Beyond War - Eckhart Tolle - Adyashanti - Tony Parsons - ThetaHealing - My conversations with Fitz - Mooji -
Recent reading Noam Chomsky,  Who Rules the World ?, (2016, Afterword 2017)
Akerlof & Shiller,  Phishing For Phools - The economics of manipulation and deception (2015) 
Mooji,  Vaster Than Sky, Greater Than Space - What you are before you became (2016)


B E I N G  A L I V E 





SL:  It occurred to me that the Association Model of Perception is as important to understanding life and living, as is Einstein's (e = mc2) to understanding physics.

The AMP describes how we take in the outside Reality and deduce from our perspective a Subjective Reality, which has Meaning to us in context of previous observations of Reality. We associate current input data with stored memory data, many of which are hard to access directly, and we respond accordingly: physically, mentally, emotionally and intuitively.


=======  to respond without resistance  =======






Biography for invited talk "My Search for the Ideal Stereo Loudspeaker", 
AES 51st Conference on Loudspeakers and Headphones, Helsinki, 2013

Siegfried Linkwitz

April 2013


Since 1999 I have been adding information to the LINKWITZ LAB website to educate about loudspeaker design, sound reproduction and recording. I provide detailed plans for DIY construction of state-of-the-art dipole and monopole loudspeakers using active electronics. The speakers are optimized for operation in reverberant domestic spaces.

After retirement from Hewlett-Packard Co. (now Agilent) in 1998 I continued to pursue my life-long interests in audio, having designed between 1994 and 1999 a line of dipole loudspeakers with moving coil drive units for Audio Artistry. While at HP I developed the "Linkwitz Transform" circuit and earlier, in 1975, the "Linkwitz-Riley Crossover" filters out of a shared audio hobby with Russ Riley.

I worked for 37 years in Research & Development at HP, on state-of-the-art electronic test equipment, such as microwave spectrum analyzers, network analyzers and EMI receivers. I traveled, teaching HP Seminars on test and measurement in the frequency range from 10 kHz to 20 GHz. During my last 18 years at HP I also participated in national and international standards development for Electromagnetic Compatibility Test Instrumentation through ANSI and IEC/CISPR 16.

I came to the US in 1961 with my wife Eike, after having received the Diplom Ingenieur degree in Electrical Engineering from Darmstadt Technical University in Germany. I continued my education with postgraduate studies at Stanford University while working at HP in Palo Alto. We have a daughter, a son and three grandchildren.








We are all inventors,
each sailing out on a voyage of discovery,
guided each by a private chart, of which there is no duplicate.
The world is all gates, all opportunities.

Ralph Waldo Emerson



Siegfried Linkwitz - Eike L. (Traut)
Monika Balsamo (Linkwitz) - Ron B. - Julia B. (18)
Andreas Linkwitz - Susan L. (Snyder) - Anja L. (13) - Danielle L. (11)
June 2017


I feel blessed, having been given a life
to contribute to understanding, consciousness and joy.


Burning Amp - 2017

"Baffle diffraction versus neutral sound dispersion"


* SL*
- Aggressive Prostate Cancer (2002) - 
- Stage 4 PrC (2016) -
- Hospice Care (2018) -










What you hear is not the air pressure variation in itself 
but what has drawn your attention
in the streams of superimposed air pressure variations 
at your eardrums

An acoustic event has dimensions of Time, Tone, Loudness and Space
Have they been recorded and rendered sensibly?

Last revised: 09/18/2018   -  1999-2017 LINKWITZ LAB, All Rights Reserved