Filter contour - roll your own?

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I'd like to have a slider to change the receiver filter contour. Something that starts off fairly soft, then sharpens up to the current shape.

My reason for asking is because at least to my ears the current filter shape is too sharp for casual use and causes fatigue over time.

Thanks,
--jim (N7CXI)
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Jim - N7CXI

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Posted 4 years ago

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Jim Gilliam

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I am not an expert on filters, but it seems if there is fatigue, you could use the equalizer to gradually roll off the lower and higher frequency content.
(Edited)
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Jim - N7CXI

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Jim - I just saw your last post.

I'm talking more about the band/white noise than the received signal, although the latter is affected to a lesser degree.

I understand it might not be a problem for everyone, but the percentage must be fairly high if virtually all recent Yaesu rigs have a contour control, and most ICOM rigs above entry level do as well. (even those with receiver EQ's)

--jim (N7CXI)
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Ken - NM9P, Elmer

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I think i understand.  It is kind of like the difference between listening to a sound system that has a smooth response vs. one that has a "peaky" response.  A person can listen without offending the ears at a much higher volume with a smooth system than with one with spikes and poor EQ, regardless of the high end or low end roll off.  As long as it is smooth.  (This has been my experience with church sound systems anyway.)  I can see that for some ears the "brick wall" might be like a rock upside the head.
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Jim - N7CXI

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Yes, that's pretty much it. We may need an acronym - "Trained Ear Syndrome (TES) " ;-)
I like your "rock upside the head" analogy.
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Guy G4DWV/4X1LT

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From what I have read in this thread and others about filters, we each seem to have our own preferences so I would second the need for as much customisation as possible. For example, Fldigi will only put a notch filter in the middle of the two RTTY signals if the rig supports it (or words to that effect). I'd LOVE a RTTY notch.
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Jim - N7CXI

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A case could certainly be made for an arbitrary response filter designer, but that goes quite a ways beyond my original request. A front-end RTTY filter would be a neat thing though, as you point out.

FWIW, I have DSP EQ software that I can use to impose whatever shape I want on the audio, but it adds yet another complication to the station. I'd much rather have all the filter fidgets in SmartSDR and not have to juggle as many balls.

--jim (N7CXI)