Wireless speaker maker Sonos priced its IPO at $15 a share Wednesday evening, below previous guidance of $17 to $19 a share.

The company and selling stockholders are offering 13.9 million shares, according to a company statement. The underwriters have been granted a 30-day option on up to 2.1 million additional shares.

Sonos had previously projected an offering range of $17 to $19 a share.

Shares are expected to begin trading on the Nasdaq Global Select Market Thursday under the symbol SONO.