Acoustica Premium 7.0.56 - Insert from Signal Generator/Spectrum

[Paulo-Brazil]

Mr. Stian,

I refer to Acoustica Premium 7.0.56, running on Windows 10 Professional 64-bit.

1. When we use the "Insert from Signal Generator", for a sweep we do use the start and end frequencies. But for a sine or a white noise, unless I am missing something, these two parameters seem to play no role in the signal generation.

Shouldn't the two sliders for the start and end frequencies be made inoperative in some uses of the signal generator? Or, in the case of the white noise, should a noise signal be generated only within a frequency band specified by the start and end frequencies? This does not happen now.

2. If I choose an audio format with a high sample rate, say 192000 Hz, and generate some white noise, the spectrogram window shows frequencies up to (I suppose) 192000 / 2 = 96000 Hz. But both an Analysis > Spectrum and an Analysis > Spectrogram only show frequencies up to around 20000 (possibly, 44100 / 2 = 22050 Hz).

Regards,

Paulo

[stian]

Hi Paulo,

1. When we use the "Insert from Signal Generator", for a sweep we do use the start and end frequencies. But for a sine or a white noise, unless I am missing something, these two parameters seem to play no role in the signal generation.

Shouldn't the two sliders for the start and end frequencies be made inoperative in some uses of the signal generator? Or, in the case of the white noise, should a noise signal be generated only within a frequency band specified by the start and end frequencies? This does not happen now.

Thanks! You're right, the start and end sliders should be dimmed for the signal types for which they have no relevance. I've added it to our tracking system.

2. If I choose an audio format with a high sample rate, say 192000 Hz, and generate some white noise, the spectrogram window shows frequencies up to (I suppose) 192000 / 2 = 96000 Hz. But both an Analysis > Spectrum and an Analysis > Spectrogram only show frequencies up to around 20000 (possibly, 44100 / 2 = 22050 Hz).

The analysis tools let you set the upper frequency limit and the default is 20 kHz. You can set it to higher values by clicking the settings button and adjusting the corresponding parameter.

Best,
Stian

[Paulo-Brazil]

Mr. Stian, thank you for the information on the settings of the Spectrum and other analysis tools.

I do not see a reason for a default of 20 KHz for the upper frequency limit in the Spectrum settings. Is there some technical reason for that? If an audio file includes frequencies above 20 KHz, it seems that this default behaviour makes Acoustica hide information about the file by design.

I think that the default behaviour for the Spectrum should be defined in a way to provide information as wide and complete as possible about the audio file. My suggestion: as default behaviour, the Spectrum module should automatically adjust the lower and upper frequency limits so that information on the whole audio spectrum (the complete range of frequencies in the audio file) is presented. If the user wishes to see a restricted view of the spectrum, then he/she could go to the settings and change accordingly one or both frequency limits.

Another suggestion: maybe, in the same way as there exists a reset button in, say, the Equalize module, the Spectrum settings window could include a reset button, to restore some parameters (block size, resolution and others) to "factory" presets. What are, if any, the suggested or recommended values for these parameters? It seems that there is no guidance about that in the Help files.

Regards,

Paulo

[stian]

Hi Paulo,

Mr. Stian, thank you for the information on the settings of the Spectrum and other analysis tools.

I do not see a reason for a default of 20 KHz for the upper frequency limit in the Spectrum settings. Is there some technical reason for that? If an audio file includes frequencies above 20 KHz, it seems that this default behaviour makes Acoustica hide information about the file by design.

I think that the default behaviour for the Spectrum should be defined in a way to provide information as wide and complete as possible about the audio file. My suggestion: as default behaviour, the Spectrum module should automatically adjust the lower and upper frequency limits so that information on the whole audio spectrum (the complete range of frequencies in the audio file) is presented. If the user wishes to see a restricted view of the spectrum, then he/she could go to the settings and change accordingly one or both frequency limits.

It's very useful to be able to zoom in on a frequency range and most users would like these settings to be persistent. That's why Acoustica loads the last settings as default values.

Another suggestion: maybe, in the same way as there exists a reset button in, say, the Equalize module, the Spectrum settings window could include a reset button, to restore some parameters (block size, resolution and others) to "factory" presets. What are, if any, the suggested or recommended values for these parameters? It seems that there is no guidance about that in the Help files.

Thanks, that's a good suggestion. I've added it to the tracking system.

Best,
Stian