The importance of flat frequency .

[thiptoman]

AR classic loudspeakers measure flatter than many loudspeakers today. Could someone who is well versed on AR loudspeakers explain why flat response is so important to accurate reproduction or reproduced sound?

[Guest]

The answer to your question should be fairly obvious. The ideal loudspeaker would (including the acoustics of the room) produce and exact duplicate of the electrical signal fed by the amplifier.

AR went through great pains to test their systems in anechonic (echo free) chamber and measure the sound output with as accurate a microphone as was available.

As discussed fairly often on these postings, most loudspeaker manufacturers put emphasis in mid or upper frequencies to make their speaker systems sound brighter---which the average person thinks is better.

I recall back in the 1960's when comparing speakers in show rooms of audio stores how the AR's were so "dead sounding" you would swear the tweeters were turned off. The same was true, to a lesser exent, with the low frequencies. All the bass reflex systems sounded "boomy" which the average person thought meant more bass. Truth is, the AR's were the accurate ones.

##### Boneske

Winneconne, Wisconsin

[kkantor]

There are many ways to think about the question:

"How good is this speaker?"

It turns out not to be as easy a question to answer as one might first think. You can test a speaker different ways, and get conflicting data. And 20 people will have 20 different opinions on which speaker is "best" on each piece of music you play for them.

In spite of this, one concept that has been widely accepted by both consumers and speaker designers is the notion of "accuracy." From this point of view, the more "accurate" a speaker is, the "better" it is. "Frequency Response" is one kind of test for accuracy. It indicates the relative equality with which a speaker translates the tones fed to its input terminals. A "flat" frequency respsonse means that all tones, low and high, are reproduced in the proper proportions. Deviations from flat response indicate that some tones are made softer or louder than they should be.

Here's a link to an article I wrote about the topic many years ago:

http://www.aural.org/resume_01_files/artic...response/01.jpg

Ken Kantor

www.intelligentaudiosystems.com

The basis of the accurate=better equation is partly scientific, partly pragmatic, and partly just plain mythology. Frequency response is not the final and complete word on speaker quality, especially since few people agree on how, exactly, to measure it. But it is a meaningful and useful spec.