So, I have this new 95% Efficient York Infinity 9M modulating furnace recently installed. All seems to work but the noise when it runs (at the "low stage", I think) is "whirry" and just plain hard to get used to. It's not that loud, there are no vibrations, but there is just a constant machinery sound that is much higher pitched than (though almost certainly not as loud as) those very low-pitched blower noises from my old furnace used to be.

Is this "different" noise just something that comes with the new technology? Or is this worth trying to minimize by tuning the system or otherwise? Are new systems necessarily supposed to be whisper-quiet?

Thank you!

No system is whisper quiet. Since you just had it installed call the dealer back for all your service needs because it should be under warrenty.