Why does SDR# sound better than SDR console?

Question

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

Answer 1

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.

Answer 2

It's not the software it is the settings. SDR Console has entirely configurable audio. In particular, under options, there is an audio section with a graphic equalizer. If it is unenabled, then you will get a flat sound. You can design different audio layouts for other applications i.e., for APT satellites; I shut down or deemphasize the frequencies not used in that form of transmission and save that pattern in the configuration. I also have one for spoken word, music, and WEFAX. SDR console uniquely can use your NVIDIA graphics card for processing and thus avoid the hiccups that might be introduced by a CPU.