For some reason, you may get not measurement graphs (don’t forget to use refresh button before complaining !). First check : be sure that you have correctly FILLED all needed fields in the upload form and SAVED the form. Also check that your recorded sound file has a valid format, …
For acoustic measurements, you really don’t need high sampling rate files to play or to record. So we choose to produce our sound files at 44.1 or 48kHz. For your recording, you can use any sample rate because the file will be resampled to 48kHz for analysis.
The method is very stable. To check it, just do some successive measurements and compare. We encourage to also measure at different levels to check consistency of your setup and your corrections. slovenska-lekaren.com In case you see differences in low frequencies, this may come from some conditions that have varied …