Stereo BoomSound speakers are among HTC One (M8)'s defining features, so it's no surprise that HTC is equipping the upcoming One M9 with similar audio capabilities. In fact, they might not be similar, but better. HTC today suggested that the One M9 will have more powerful BoomSound speakers. The company posted a short teaser video on Twitter, alongside the comment "get your hands on bigger boom." The video (embedded below) doesn't really reveal much, but it's pretty clear that we should expect the One M9 to have very loud speakers. According to a previous report, HTC may have partnered with Dolby Laboratories in order to pack Dolby 5.1 audio technology into the One M9. Just like Samsung, HTC will announce its next flagship handset on March 1 at MWC 2015. The new smartphone will most probably have two variants: One M9 (with a 5-inch 1080p display), and One M9 Plus (with a 5.2-inch Quad HD display). We assume that both will feature exactly the same improved BoomSound speakers. But we'll see on March 1 if we're right or not.