Just setting up Audacity on a new computer.
I was sure all the sound from my new computer had a reverb effect applied,
(despite all the audio enhancements being turned off).
So I generated a mono bleep in Audacity, and recorded it in stereo, (via stereo-mix).
Low & behold, reverb …
(apart from latency, the red waveforms should be identical to the green original).
How did you get Audacity to record itself? Computers want to play to the outside world and record from the outside world. There is no play and then record that playback unless you applied special routing apps or other software.
Routing apps and other software can generate feedback loops and other uncontrolled pathways leading to reverb and echoes.
The sound card can do that. I got a machine from Systems and I couldn’t get it to pass quality enough to put in service. The sound card had “Cathedral Effects” stuck on.