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Author Topic: Stereo Tool Absolute Highs DSP Filter  (Read 648 times)

Offline RobRich

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Stereo Tool Absolute Highs DSP Filter
« on: April 16, 2018, 0145 UTC »
Do not expect a miracle, but the Absolute Highs filter in Stereo Tool can sometimes help reproduce another KHz or few when listening to narrow content.

https://www.stereotool.com/

For a quick setup, configure the maximum generation setting at or slightly below the top edge of your current filtering and/or received bandwdith. Bump up the gating if needed to process more of the desired content instead of background noise.

Content is the huge YMMV factor. For example, forget it with lots of noise IMO, as it likely is going to enhance the noise as much as the desired content.

Pictured below is an 80m band voice comms example. Filter width is just 2.7KHz to limit adjacent interference, but it sounds considerably wider with the Absolute Highs filter enabled.
« Last Edit: April 18, 2018, 0103 UTC by RobRich »
Tampa, FL USA | US Map Grid EL88
Kenwood R-600 + R-2000 | 2x RTL-SDR V3 | Si-Tex 200 | Soft66LC4 | Yaesu FRG-7
Ameco PCL-P | MFJ-784B | MFJ-901B | 2x MFJ-1020B | 2x Timewave DSP-9
148' "Shielded" Loop-on-Ground | 18' End-Fed Vertical | 9' + 31' Verticals

Offline redhat

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Re: Stereo Tool Absolute Highs DSP Filter
« Reply #1 on: April 17, 2018, 0519 UTC »
Does the 'delossifier' have a similar effect?  I think it is intended to fill in spectral holes left by MPEG compression.  Hans' declipper and dehummer process works amazingly well too.

+-RH
« Last Edit: April 17, 2018, 0522 UTC by redhat »
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Offline RobRich

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Re: Stereo Tool Absolute Highs DSP Filter
« Reply #2 on: April 17, 2018, 2217 UTC »
As far as I understand, Delossifier mathematically fills spectral holes in existing spectrum while Absolute Highs mathematically generates additional spectrum.

I do not have a Delossifier license.... yet? Have not made up my mind on the cost.

I occasionally use Perfect Declipper as well since lots of transmissions, including some of the mainstream broadcasters, are heavily clipped.
Tampa, FL USA | US Map Grid EL88
Kenwood R-600 + R-2000 | 2x RTL-SDR V3 | Si-Tex 200 | Soft66LC4 | Yaesu FRG-7
Ameco PCL-P | MFJ-784B | MFJ-901B | 2x MFJ-1020B | 2x Timewave DSP-9
148' "Shielded" Loop-on-Ground | 18' End-Fed Vertical | 9' + 31' Verticals

Offline RobRich

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Re: Stereo Tool Absolute Highs DSP Filter
« Reply #3 on: April 18, 2018, 0100 UTC »
Processing reception of Seven Trees Radio tonight.
Tampa, FL USA | US Map Grid EL88
Kenwood R-600 + R-2000 | 2x RTL-SDR V3 | Si-Tex 200 | Soft66LC4 | Yaesu FRG-7
Ameco PCL-P | MFJ-784B | MFJ-901B | 2x MFJ-1020B | 2x Timewave DSP-9
148' "Shielded" Loop-on-Ground | 18' End-Fed Vertical | 9' + 31' Verticals