Meeting Topic: Designing for Ultra-Low Distortion and Noise
Speaker Name: Bruce Hofer
Meeting Location: Devlin Hall, Boston College, Chestnut Hill, Massachusetts
Designing for Ultra-Low Distortion and Noise in Analog Circuits, circa 2015
This was a thought provoking discussion of analog circuitry design with particular emphasis on practical, real world solutions. The presentation focused on objective, measurable imperfections that limit analog circuit performance. Mr. Hofer presented highly detailed information of the various parts used in electrons and how their specifications affect the noise levels of electronic circuits. He showed how the noise of a circuit can be predicted and how closely the prediction will match the measured noise. He also ephisized how layout affects the noise levels of circuits.
About Bruce Hofer:
Bruce is one of the founders of Audio Precision and is currently its Chairman. Bruce focuses most of his time on new product development and technical research. Bruce's passion and expertise are in the areas of analog circuit design, ultra-low distortion signal generation and analysis, and wideband linear signal amplification. Indeed, insiders often refer to him as the "precision" in Audio Precision.
Bruce's career with state-of-the-art instrumentation began almost 46 years ago during the summer of 1969, when he was hired by Tektronix as a student engineering assistant. He completed his BSEE degree from Oregon State University in 1970, and then spent the next 7 years at Tek designing high-speed sweep generators and horizontal deflection amplifiers for their 7000-series oscilloscope family.
In 1978, Bruce left the world of oscilloscopes to become engineering manager and the senior engineer of the Tektronix TM500 group that developed the SG505 audio oscillator and AA501 fully-automatic distortion analyzer. Although these instruments were successful, Tek's upper management decided they did not fit into the long term strategy of an oscilloscope company. By then, the mixture of opportunity, talent, and entrepreneurial spirit had reached a critical mass. In the autumn of 1984, Bruce and three fellow team members resigned from Tektronix, and launched a new company called Audio Precision.
Bruce has received 13 patents and written many technical articles and papers. He has made numerous technical presentations to various sections of the Audio Engineering Society and other organizations, and has also served as a guest lecturer at Oregon State University and the Oregon Graduate Center. In 1998, Bruce was inducted into the OSU "Engineering Hall of Fame" as one of its charter members. Bruce has been a member of the Audio Engineering Society since 1977 and received its Fellowship Award in 1995.
Written By: Lou Clark