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This is kind of odd. I just got my first SDR receiver and I noticed that one application (SDR#) sounds a lot better than another (SDR Console) when listening to stereo FM broadcasts through the same antenna, in the same position, at the same time, with similar settings. I set up all of the configuration options as close as I could but the difference persists.

I'm totally new to radio and I don't have any idea where to start. Does anyone recognize the audio difference between the two clips, or have ideas about what could be causing it?

SDR console audio clip
SDR# audio clip

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I'm not familiar with the behavior of the particular programs you've named, but the obvious (guessed by ear and confirmed with a spectrogram/waterfall tool) difference between these two clips is the audio bandwidth is different.

  • The clip from SDR Console has audio occupying about 5 kHz of bandwidth, in a file with a 12 kHz sample rate.
  • The clip from SDR# has audio occupying about 15 kHz of bandwidth, in a file with a 39.062 kHz sample rate. (An odd rate for audio, presumably chosen for convenience given SDR#'s internal sample rates.)

So, the clip from SDR# has more of the music's high-frequency content preserved. Also more background hiss — because of that, more bandwidth isn't necessarily going to sound better in all ways.

To see if you can get comparable results, look for terms like for audio bandwidth, filtering, or sample rate. (Ones specific to the WFM demodulator or the audio output section, not your RF input sample rate!) It's also possible that the recording function has its own limits.

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