After migrating from Windows to Linux and with this from SDR Console to the AMSAT-DL QO-100 Linux Transceiver, I had the issue that my transmitted audio was a bit weak in the treble. The solution to this was to install and configure the software equalizer PulseEffects to modify my microphone audio before it gets fed into the SDR application.

Installation

On Debian/Ubuntu Linux this application can be easily installed with the following command:

# sudo apt install pulseeffects

Configuration

After starting PulseEffects, the following steps need to be performed:

• Click on the microphone icon on the top left (1)
• Enable the slider “SoundIO” (2)

• Select “Equalizer” from the left menu
• Make sure the equalizer is enabled by checking the box on the left
• Click on the tools icon (3)
• Presets (4)
• Load the preset “ziyad_perfecteq” (5)

Loading this preset can be omitted but it helped me to easily reduce the number of sliders.

• Setup your audio to your likings (6 and 7)

Save your own preset by

• clicking on (8),
• selecting audio input (9),
• entering a name,
• clicking the + button
• and making the settings persistent (highlighted symbol in the screenshot)

• enable “start service at login” in the settings screen

Results

The following screenshot shows my signal on the waterfall with the equalizer disabled (left side) and how the signal looks like with the above settings applied (right side):