Synchronized Swept-Sine: Theory, Application, and Implementation - October 2015
Effect of Microphone Number and Positioning on the Average of Frequency Responses in Cinema Calibration - October 2015
The Measurement and Calibration of Sound Reproducing Systems - July 2015
Phase Intermodulation Distortion Instrumentation and Measurements
Phase intermodulation (PIM) distortion in audio amplifiers, in particular that which may arise from the use of negative feedback, is considered. PIM theory is discusseed and the linking of PIM to amplitude intermodulation (AIM, or SMPTE IM) distortion is illustrated. It is noted that amplifiers without negative feedback are also likely to produce PIM. Coherent SMPTE IM instrumentation capable of resolving less than 2 ns of equivalent time dispersion and measurement results from several different real amplifiers are presented. The results show that PIM is not a problem in contemporary amplifiers and suggest that negative feedback reduces total PIM in most cases.
Click to purchase paper or login as an AES member. If your company or school subscribes to the E-Library then switch to the institutional version. If you are not an AES member and would like to subscribe to the E-Library then Join the AES!
This paper costs $20 for non-members, $5 for AES members and is free for E-Library subscribers.