The propaganda about scroll compressors says they are inherently quieter than piston compressors. However, as I walk around my neighborhood, there is a noticeable and annoying hum/buzz from all the scroll compressors regardless of brand. Way more noticeable than the older piston units. I hear a "waaaaaah" from the new units and only fan noise from the older squatty units.
I think my unit was quieter when it was first replaced, but perhaps I was so grateful for a cool house, I didn't care. It's not any louder than everyone else's. I measured the noise with a db meter at my unit, and it is at 72db. Not too loud. but at a very annoying frequency. Now that all my adjacent neighbors have new units, it's impossible to sit outside in the summer for all the noise. So what is normal scroll compressor noise? What sounds indicate a problem? Do we all have problems? Or is it just me being sensitive to the scroll compressor frequency?