Netflix (NFLX.O) soared 15% in premarket trading after the world's No. 1 streaming company by subscriber count said it was raising prices for some of its plans in the United States, Britain and France after adding 9 million users in the third quarter.
Tesla (TSLA.O), however, slid 6.1% as the electric-vehicle (EV) maker missed Wall Street estimates for third-quarter gross margin, profit and revenue.
CEO Elon Musk said on Wednesday he was concerned about the impact of high interest rates on car buyers, adding that the EV maker was hesitant about its plans for a factory in Mexico.
Legacy automakers Ford Motor (F.N) and General Motors (GM.N) lost around 1% each.
Yields on benchmark Treasury notes slipped from session highs, but the 2-year yield, which best reflects short-term interest rate expectations, was still at a 17-year peak at 5.2228%, while that on the 10-year note stood at 4.9364%, near the 5% level last seen in 2007.
"Is the 10-year going to breach 5% in yield ... I think the answer to that is yes, that it can in turn provoke even more volatility," said Russell Hackmann, President of Hackmann Wealth Partners.
"That's a psychologically important issue that maybe could trigger a real sell off in stocks ... you got a jittery market out there."
Powell is scheduled to speak at 12 p.m. ET, while other Fed officials including Chicago Fed President Austan Goolsbee, Atlanta's Raphael Bostic and Philadelphia's Patrick Harker will speak later in the day.
Fed policymakers on Wednesday signaled a pause in hiking interest rates for another couple of months as they wait for signs of progress in their fight against inflation and the potential for the recent rise in long-term yields to do some of their work for them.