Searching for the Best Speaker Sound: What does 'speaker accuracy' mean?
Q. When you allude to the "accuracy" of Axiom speakers, what exactly do you mean? I’ve looked around for a good definition of accuracy but there seem to be many. What is the definition you are using? Is it about the best speaker sound? — Mike B.
A. Well, at Axiom we mean the speaker reproduction is as close as possible to the original recording or performance. Though this may sound fundamental, it's surprising how few speakers are designed to this goal. From a measurement perspective this generally translates into a "linear" response. The speaker should evenly reproduce deep bass, upper bass, midrange sounds (including male and female vocals) and treble high-frequency sounds, neither exaggerating nor suppressing any segment of the tonal range, in order to qualify for the best speaker sound. If you drew a graph of a speakers response to every sound audible to the human ear, it would ideally be a straight horizontal line (hence the term "linear").
We actually calculate the way an Axiom speaker responds to sound by putting it inside an anechoic chamber (a room with no echoes), feeding it tones representing every frequency audible to humans--from the deepest bass at 20 Hz to the highest frequencies at 20,000 Hz--and then measure the speakers output with a microphone, graphing the results on a chart. An accurate or linear speakers output should approximate a smooth horizontal line, free of peaks or valleys in response. This would represent accurate reproduction of every frequency audible to the human ear and would be the speaker’s "frequency-response curve."
Since these same measurements can be performed at various axis degrees which causes them to change, the real designing comes in understanding the relationship of the entire "family" of curves and their eventual overall effect on the listening performance.
For more detailed information on finding the best speaker sound, read How To Judge Speaker Sound And Accuracy.
About the Author
Alan Lofft was, for 13 years, Editor in Chief of Sound & Vision, Canada's largest and most respected audio/video magazine. He edited Sound & Vision (Canada) until 1996, when he moved from Toronto to New York to become Senior Editor at Audio magazine.
Lofft has been writing about hi-fi and video professionally for over 20 years, ever since his first syndicated newspaper column, "Sound Advice", began appearing weekly in The Toronto Star, Canada's largest-circulation daily newspaper. In the late 1970s, he became a contributing editor, columnist, and equipment reviewer at AudioScene Canada, the leading national consumer electronics magazine at the time.
He also wrote on consumer electronics for Maclean's magazine and made occasional appearances on TV on "Canada AM," the national CTV morning show, and on June Callwood's national afternoon TV talk show.
In 1983, he was appointed editor of Sound Canada magazine, which he relaunched in 1985 as Sound & Vision, incorporating video content and reviews as well as hi-fi and audio features. He also became a contributing editor to Stereo Review in New York, and an audio columnist for Music Express, a Canadian rock magazine.
An audio and electronics enthusiast from childhood, Alan began building vacuum-tube hi-fi gear for his father, who was an audiophile in the 1950s. Lofft's passion for audio continued through college, during which time he hosted and produced "On Campus", a radio show taped on location (on a portable Ampex 650 open-reel recorder) at Wilfrid Laurier University and broadcast locally in Kitchener, Ontario.