[Elecraft] On K3 crystal filter gain compensation (FLx GN)

[wayne burdick]

Lately there has been some discussion about how much gain to add when 
compensating for loss in the K3's individual crystal filters. The 
general guideline is "as little as possible." I'd suggest starting with 
0 and working up to as high as a few dB only if it seems necessary.

Narrow bandwidths themselves create a psychoacoustic "gain" effect, so 
you don't really have to make up for the entire loss relative to wide 
filters. Also, excessive gain can in extreme cases worsen the 
performance of DSP signal processing, such as noise reduction (NR). 
Finally, AGC tends to flatten signal amplitudes in general, further 
reducing the need for per-filter compensation.

While I'm on this topic, I'd also like to suggest using a minimum of 
both RX and TX EQ. The '0' levels were carefully determined 
empirically, and in most cases the optimal values will be well below 
the maximum range provided. Unless you have an aural sensitivity issue 
in some pitch range, or a serious mic deficiency, I'd stay between +/- 
6 dB. As with filter gain settings, excessive values can result in 
adverse interaction with the DSP.

And yes, there will be per-mode RX EQ in a future firmware revision. 
Thanks for all the suggestions on this.

73,
Wayne
N6KR

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