Wow: SoundHound powering 4M voice searches a day

Buzz around voice recognition technology is louder than ever, thanks to the debut earlier this month of Apple’s iPhone 4S (s AAPL), which includes a voice recognition and virtual assistant feature called Siri. But Apple isn’t the only one seeing benefits from focusing on this kind of technology.

SoundHound, the company that makes voice recognition apps for music and song search, released user figures for the first time on Tuesday — and the numbers are pretty impressive. The company now has 50 million users worldwide on iOS and Android; (s goog) its service is processing more than 4 million music searches per day, and receiving 1,000 hits per second. SoundHound’s growth has been speeding up significantly of late: The new metrics in 2011 represent a tenfold increase in usage since 2010, the company says.

Not an overnight success

To be sure, SoundHound has been building toward this for some time. The company began in 2005, as founder Keyvan Mohajer was studying for his Ph.D. at Stanford and dedicating his studies to voice recognition technology. SoundHound has raised $16 million to date and as of this past summer had around 55 employees.

The company’s flagship SoundHound app identifies songs that a user sings or hums; its newer app, Hound, debuted in May and can identify when a user says the name of an artist, album or song. More recently, SoundHound has debuted integrations with iOS 5 and iCloud and announced a partnership with the popular on-demand music streaming service Spotify.

Competing against the big dogs

But will the increasing interest in voice recognition technology by larger companies such as Apple ultimately render SoundHound moot? It could, but it’s not a certainty by any means: SoundHound owns all the technology that powers its apps, and Mohajer’s name is on three patents pertaining to voice recognition, so the company is unlikely be copied without a fight.

It’s more likely that SoundHound will emerge as an acquisition target for a larger company keen to get into the space. That’s probably one of the reasons SoundHound’s investors, which include the first investor in Pandora (s P), Larry Marcus, have backed the company. It’s been a long road for SoundHound, but it will be interesting to see what’s ahead for the company now that its technology has headed toward the mainstream.