Ask HN: Best ways of distributing market research surveys?

I'm in the process of testing out a few ideas and want to get a quick pulse on user needs in a statistically useful and out-of-my-social-bubble kind of way. So I turned to surveys via Qualtrics.

I've gone the usual route of sharing an anonymous link to the survey via social media and asking friends and family to re-share.

What are some other time and cost effective ways of getting the survey link out to people? Taking out ads online? Trying out one of the services like Pollfish or Centiment?