I have been asked a few times what then difference is between an AT822 and an NT4. I don’t have any A/B style recordings in sound, but I can offer some opinion based on using them.
I won’t dwell on the technical differences as these are quite easy to google but briefly, both are single point stereo microphones with capsules in X-Y configuration.
Power: Both mics are battery powered (NT4 9V or phantom, AT822 1.5V) so work well with things like minidisc and a zoom H2. This means that the NT4 works well with almost everything but the AT822 is better with plug-in power type devices.
Weight: The NT4 weighs about double (I would guess but have not weighed them on scales) that of the AT822. This could important for when you end up standing like a statue to capture a sound you weren’t expecting.
Costs: The NT4 also costs about double what an AT822 does. My at822 was £120 via ebay and the NT4 was £240 via competetive high street store.
Sounds: The AT822 I would say is better at soundscapes (wide sounds with lots of variety/range), in that it picks up and handles off axis sound better than the NT4, but then the NT4 is more accurate and directional. The NT4 also picks up sound from behind the MIC array – something that I don’t think the AT822 does. One important difference for the casual user is the AT822 is better at handling windnoise and comes with a lowcut/filter. The NT4 will distort in a very low draft, whereas the AT822 handles well with the low pass filter.