[Elecraft] Meaning of EQ bands?

[Ian White GM3SEK]

Joe Subich, W4TV wrote:
>
>> The existing K3 manual seems quite misleading in talking about 8
>> "bands" of audio equalization. We now learn that the EQ facility
>> allows the user to set the relative levels at 8 discrete frequency
>> POINTS, and that the rest of the frequency response is interpolated
>> by "joining up the dots".
>>
>> That gives quite a different shape to the frequency response than
>> many will have imagined.
>
>How so?  That's the way "graphic" equalizers - whether they are octave 
>or fractional octave - have operated for years.
>

Please re-read what Lyle wrote. The underlying DSP does not use stepped 
frequency "bands" at all - not even as a concept.

Whenever we use words to describe DSP, we are always at least one step 
away from reality. So let's not make that any worse than it has to be.

A more accurate image of what's really happening is that the equalizers 
re-draw the frequency response curve by specifying its values at 50, 
100, 200, 400, 800, 1600, 2400 and 3200 Hz.  "Drawing a curve" gives a 
much more accurate picture of what is really happening, especially at 
frequencies in between those points.


Fortunately, the K3 doesn't care about any of this. For the first time 
in almost 50 years I'm receiving unsolicited compliments about my audio 
- so whatever is happening in there, it works.


-- 

73 from Ian GM3SEK
http://www.ifwtech.co.uk/g3sek