The evaluation of a loudspeaker's transfer function or frequency response (amplitude and phase) via digital processing of its measured impulse response is now an established technique. During ten years experience with the method, many practical problems of measuring accuracy were encountered. This paper will discuss the causes and suggested remedies for reducing measuring errors, particularly at low frequencies, due to drive unit nonlinearities, signal averaging in the presence of both random and synchronous background noise, and DC offset in the A/D converter. In addition, a novel method for accurately determining the free field response of a loudspeaker system down to very low frequencies will be presented. It will be shown that it is possible using this method to estimate a loudspeaker's frequency response to an accuracy of better than 1 dB down to 20 Hz using only 10mS of its impulse response measured in a non-anechoic environment.
https://www.aes.org/e-lib/browse.cfm?elib=11709
Click to purchase paper as a non-member 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 $33 for non-members and is free for AES members and E-Library subscribers.
Learn more about the AES E-Library
Start a discussion about this paper!
