Home Entertainment Show 2007

Listening & Measurement Workshops

Workshop #1
Amplifier Measurement Clinic

How are amplifier measurements done, what do they mean, and do they have any real value? This amplifier measurement clinic will show attendees how audio power amplifiers are measured and which measurements are important. Power amplifiers will be measured in a fashion similar to those published in Stereophile equipment reviews. This clinic will be conducted by Bob Cordell, who is an amplifier designer experienced in tube, bipolar and MOSFET amplifier designs. Bob has also worked in the forefront of developing new and more sensitive distortion tests for amplifiers. These include Multitone Intermodulation (MIM) and Phase Intermodulation (PIM) tests, as well as distortion magnifier techniques for measuring ultra-low levels of THD, crossover and TIM distortions. Measurements on actual amplifiers will be made and differences in measurements and design will be discussed. Bob will share his views on why amplifier measurements are not always a good predictor of sonic differences. Vendors will be invited to take advantage of this opportunity for measurement of their amplifiers, either in a public setting or in private.