(Note that you'll have to be listening to some sort of sound for them to be maximally effective; simply turning on the noise cancellation without playing music or some other sound through them reduces the noise, but not by as much)
I was actually thinking of wearing earplugs and headphones at once. Thanks for the info
After having gone through a number of pretty expensive NC headphones, I can say confidently that up until now nothing matched late-model Bose for NC specifically (music sound quality is another discussion). Parrot came closest, but everything else was way behind and really only blocked airplane/subway/bus-type loud hum, nothing more random or higher-pitched.
However, the initial reviews for the 1000X have all been pretty adamant that the 1000X matches and possibly beats the QC35 for NC. That's an amazing accomplishment for Sony, no lie.
At any rate, you're welcome. I have really bad noise sensitivities that make productivity hard in shared spaces, so your question is near and dear to my heart.
A set of one of those will probably do the job of lessening voices to something acceptable--they do to the point that my very, very distractable self can work in an open office, whereas older NC headphones did not--but they won't completely remove it.
If you really want that, I'd suggest a set of 34dB+ reduction earplugs. If that doesn't work, put them underneath NC over-ear headphones. If that doesn't work, play white noise on the headphones. I'll be surprised if you heard anything external after that.