Moving faster as a digital business means communicating faster and more efficiently. Voice has continued to be a preferred way to communicate due to its ease-of-use on the go. When combined with email communications, these two ways of communicating dominate interactions within the enterprise today. That said, the challenge for enterprises is that voice-based conference-calling services can eat up a large part of the telecommunications budget. New players are challenging that approach, by offering a combination of both PSTN and VOIP audio capabilities, making it easier for anyone to call from any device, at any time. This research note identifies three emerging Hot Vendors in Audio Conferencing.