AnalogSteph
Major Contributor
FWIW, I could export a 20000 Hz to 96000 Hz linear sweep as WAV just fine after selecting 192 kHz as the sample rate. It just doesn't let you enter anything past fs/2, which makes sense if you think about it. For realtime generator use, you'd have to change the sample rate in settings.or a sweep from 20kHz upwards but the REW generator doesn't seem to allow me to do these.
Also, there's obviously other spectrogram software, but many will be familiar with Audacity already as it is a popular free general purpose audio recorder / editor that many of us will have used for something already. I did all my FM radio recording with it back in the day.
(Important: On Windows, use the WASAPI sound library to get past 16 bits per sample. You can get ASIO support if you compile a build yourself.)