Google declined to comment on the price and details of the deal.
"Our technology enables smartphone manufacturers to reclaim valuable space within phones, which could be filled by a bigger battery", Redux Chief Executive Nedko Ivanov said at the time.
Redux raised $5M last spring and had granted 178 patents.
It is unclear when Alphabet - via an Ireland-based subsidiary of Google - acquired Redux, but the transfer of shares of Redux holding company NVF Tech Ltd.to the US tech giant was confirmed on December 13, according to United Kingdom regulatory filings. But in the recent years, Google and other Alphabet subsidiaries have started focussing quite a lot on hardware products including Pixel smartphones, which seems like a good place to use the tech. It also creates solutions to create so-called haptic feedback, which allows users to carry out different tasks on current smartphones by applying different pressure to the screen.
According to its page the company 'developed breakthrough technology which transforms the user experience by bringing surfaces to life with Sound and Touch'.
The takeover of the sound specialists could see an influx of new engineering talent for Google that could help the company incorporate better sound systems into its handsets in the future. The current Pixel 2 and Pixel 2 XL were criticized by some quarters for not trimming their bezels quite as aggressively as other devices on the market did.
Alphabet has a range of potential uses for the technology. Google Inc (GOOG) is now the proud owner of Cambridge-based startup Redux. At the CES consumer electronics conference in Las Vegas this week, Google is heavily promoting its voice-controlled speakers that compete with Amazon.com Inc.'s Echo device.