High-definition (HD) voice quality not only changes the way we hear those on the other side of the phone, but has created a new level of quality users expect with their communications services.

On a VoIP network, HD Voice improves user perception of the technology while still offering the cost savings VoIP has become so popular for.

Ooma is a VoIP provider focused on voice quality. With Ooma PureVoice HD technology, customers are able to enjoy calls with what officials say is, “the utmost voice clarity.”

I recently caught up with Dennis Peng (News - Alert), vice president of product management and co-founder of Ooma, to find out more about HD Voice, Ooma’s offerings, and to get his thoughts on the market.

Our exchange follows:

The use of HD Codecs in VoIP has set all new standards in the quality of voice users are now coming to expect. Can you describe some of the latest improvements in HD Voice?

HD Voice delivers a rich, vibrant, more natural and life-like reproduction of the human voice by greatly expanding the amount of speech information carried by the phone network. The traditional phone network filters out a substantial portion of speech frequencies which makes people sound different than do in real life and, while speech is normally intelligible, it still sounds muffled.

HD codecs make it possible to capture a much wider range of the human voice -- up to two octaves higher on the high end and two octaves lower on the low end -- which makes for calls that sound like you are talking in the same room.

While HD Voice is already the early stages of deployment in large business networks, Ooma is the first residential telephony service to bring the benefits of HD Voice to regular consumers.

In what ways has HD Voice improved user perceptions of VoIP?

VoIP has traditionally been sold and marketed as a way to save money, but HD Voice is an excellent example of how VoIP can be used to create a vastly better user experience in a universally relatable way. Listening to an HD phone call for the first time can be an ear-opening experience; we have been trained for so long to expect so little from the telephone that most users don't even realize what they are missing. But if you compare a standard definition phone call with a high-definition call side-by-side, the difference is like night and day. It's very similar to going from standard definition video to high-definition video. Once you've seen high-definition, it's hard to go back. The same holds true for HD Voice.

Is HD Voice also possible for mobile calls using VoIP?

Yes, with the launch of the Ooma Mobile HD App earlier this year on Apple (News - Alert) iOS and Android phones, you can take HD Voice calling on the road with you. Not only do you enjoy the incredible clarity and more natural, life-like voice associated with HD, you're not using minutes from your cell phone plan when you make the call. The call is made your phone's WiFi (News - Alert) or 3G Internet connection, so you're saving money while enjoying a better quality call.

Can you talk a little about Ooma’s PureVoice HD Voice technology and how it’s able to deliver clear voice calls?

Ooma PureVoice HD encompasses four key technologies:

First, we use an advanced low-bandwidth codec that delivers excellent voice quality while reducing the amount of bandwidth required. This is especially important when trying to use VoIP over an entry-level broadband service.

Second, we have developed an adaptive algorithm for detecting packet loss on the Internet and compensating for the loss through the use of redundancy. This industrial grade technology is normally used in mission critical operations for large businesses, but we've adapted it for use with consumers.

Third, we enforce strong Quality of Service when our device is plugged into the user's home network. When installed in front of the home router, we can dynamically reserve the needed bandwidth for a voice call without letting other network traffic, such as a file upload or video stream, interfere with the quality of the call.

Fourth, we are the first residential phone service to deploy HD Voice so that our users can enjoy the impeccable quality when they converse with their friends and family who also use Ooma.

Together, these technologies allow Ooma to deliver the best sounding, most consistent voice quality in the industry.

Ooma Telo handsets offer the proper equipment needed for a true HD Voice call. Can you talk a little about the technology behind these devices?

Standard cordless phones are not capable of supporting HD Voice because they have been optimized for use on traditional phone networks. Even the latest DECT (News - Alert) 6.0 phones use a primitive codec to digitize and compress the voice signal as it is sent over the air. While the quality degradation is negligible for calls made over the regular telephone network, it completely negates the benefits of HD Voice.

Because Ooma handsets were engineered from the ground up with HD Voice in mind, we implemented custom extensions to DECT to double the effective bandwidth over the air. This allows us to utilize an advanced wideband codec which delivers the stellar voice quality associated with HD Voice.

It’s been said that HD Voice calls may actually increase the duration of calls. What are your thoughts on this?

I think it is very natural for people to spend more time on the phone when they can hear each other in HD. The rich, vibrant, life-like sound that HD Voice produces boosts clarity, improves comprehension, and makes for a much more enjoyable experience.

The science behind why talking over HD Voice is more enjoyable goes like this. When you call over the traditional phone network, your brain needs to work harder to interpret the sounds that you hear. Much of our speech information is filtered out by the old, legacy phone network and your brain needs to reconstruct the intent of the speaker by filling in the missing information using speech context and other subtle audio cues. Some of the speech information can't be reconstructed reliably, which is why it is easy for us to misinterpret certain letters like "f" and "s" or "d" and "p.” Although this is all happening subconsciously, the active role your brain has to play when talking over the traditional phone network means you need to stay more focused, spend more time clarifying things, and fatigue more quickly.

With HD Voice, we are able to more than double the speech information that is transmitted from speaker to listener. The higher fidelity speech requires less mental load for recognition and comprehension which means that you have more time to enjoy the conversation!

As an aside, although the convenience of the cell phone is undeniable, you are making significant compromises in terms of voice quality. Not only do you normally have higher end-to-end delay, you often have more background noise (often due to the environment) and the overall audio quality can further degrade due to poor signal reception. We probably can all recall cell phone calls where you couldn't wait to get off the phone because it was so difficult to have a conversation. So if poor quality leads to shorter duration calls, it probably is no surprise that a good quality call, especially an HD call, will lead to longer duration calls.

Are there any upcoming developments for the HD Voice market to keep an eye out for?

HD Voice calling is currently limited to users in the same community, on the same service. HD peering promises to enable users on disparate services to connect to each other in HD rather than connecting to each other on the legacy phone network and suffering the associated degradation in audio quality. While the economics and business case of HD peering remain to be proven, we are strong supporters of both HD Voice and HD peering and are working to proliferate both technologies.