Built-in microphone 1 input channel on MacBook Pro 16-inch (2019)

Hey folks!

I recently bought a brand new MacBook Pro 16-inch (Catalina) and I noticed that in the "Audio MIDI Setup" app there is only 1 input channel for the built-in microphone:

On the other hand, on my older MacBook Pro 13-inch (Late 2013) running Mojave, I see 2 input channels:

I just wanted to ask you guys if this is normal. I am expecting that I should see -may be- 3 input channels on my MBP 16-in. Can anyone confirm that they also have a similar situation?

Thank you in advance!