Unless you have been living under a rock for the last year, you probably have read, seen or if you are lucky, experienced what many to consider to be VoIP’s killer feature: High Definition (HD) calling. Pioneered, brought to market and championed by Polycom through their HD Voice technology, HD VoIP is quickly gaining thousands of converts as it’s popularity continues to swell as this next wave of more discerning converts finally switch to VoIP. For a technology that is highly lauded by those who both produce and use it, there is still a lot that is not known about it and misinformation about HD VoIP amongst the industry and the customers it serves.
So, what better way to educate and dispel myth’s then to get the straight facts from the guy who co-founded the company leading the HD VoIP charge and also serves as the CTO for the companies voice division?
The following is a three part interview series with Polycom Co-Founder and CTO of the Voice Division, Jeffery Rodman. Jeff has been at the forefront of audio and video communications for most of his career. Following a BSEE Cum Laude and MSEE in electronic engineering from CSUN, he spent six years developing and enhancing video and test capabilities for military guided missile systems for Hughes Aircraft Company. During this time he also created a novel approach to sound synthesis that formed the foundation for his Master’s thesis, and co-founded Specialty Video Systems to market digital video effects to the entertainment industry.
In 1980, he joined Harris Video Systems where he became Director of Engineering, pioneering new digital video processing systems for broadcast and production applications. In 1984, Rodman was recruited to build a hardware engineering organization and implement a revolutionary architecture for the new start-up PictureTel (then PicTel), building the foundation for a family of systems that has transformed the videoconferencing industry, and continued as Director of Hardware Development through PictureTel’s formative years. Rodman co-founded Polycom in 1990 and has been instrumental in the realization of Polycom’s iconic products for voice, video, network communications, and other media.
Needless to say, Jeff knows voice. Now that we got that out of the way, let’s get started with Part 1 of this interview series on HD VoIP…
Jeff, HD Voice has generated plenty of interest for several years now. But lately it seems like it’s really getting legs – why are companies more ready now for wideband audio?
Over the past couple of years, VoIP has become the primary medium for phone networks and upgrades. And once you have moved from a POTS-style network to an IP network for your communications, it dawns on you that your network is suddenly transparent. It’s not designed to carry only stuffy, 3 kHz audio anymore; it can now carry anything you can imagine.
The benefit of wideband audio is obvious, especially once you hear it. Remember that everything we hear today, from satellite and FM radio, to records and CD’s, to television, and even our oven timers, is already wideband audio. When we have a drink with friends or sit around a table with our co-workers, our voices are HD Voice, our ears are accustomed to hearing the whole speech spectrum. It’s only the phone, which is one of the most critical tools in business, which has become the last holdout of poor audio. So increasingly, as people hear about HD Voice and ask how it would fit on their network, they are finding that it’s a simple, robust, and economical enhancement of the system they already have.
Very interesting point. So, what events or industry movements are impacting the proliferation of HD Voice today?
More and more VoIP telephones are including HD Voice in their basic function sets because it adds value and helps efficiency without significantly affecting cost. And it’s industry-wide; many vendors including Polycom, are shipping compatible, wideband-capable IP phones. Another trend is that companies are realizing that telephony is moving to wideband, and are choosing wideband-capable phones for their capital investments today, because they don’t want their companies to be stuck with obsolete phones years before they’re depreciated.
You mentioned HD Voice enabled IP phones, but what other key elements are required for a great HD Voice experience?
At its simplest, all you need are two people having an interesting conversation over great HD Voice phones connected by an HD-enabled network. The network is pretty easy; any VoIP network that can carry voice is already capable of carrying HD Voice because modern wideband bit rates are comparable with existing narrowband codecs. The IP-PBX or service provider needs to have added at least one wideband codec (“coder-decoder” or translator, most often G.722) to their repertoire, but most have either done this already or have it in their roadmaps.
The phone is the most important key to good wideband performance, and this is why you want to choose a vendor with a strong track record for great sound. Even today, there are some “wideband capable” phones out there that add a wideband codec without changing the rest of the speech path. When you do this, it’s like talking to a friend through a pillow: you’re speaking wideband, and they’re hearing wideband, but the stuff in between is choking your voice down to narrowband. To keep this from happening, the phone has to be designed from the ground up to carry the full range of human speech: high-performance microphones, electronics, acoustic design, loudspeaker subsystems (yes, even a phone’s loudspeaker is complex subsystem, it’s not just shoving a speaker in a box), and so on. Wideband sound even acts differently, so the algorithms (like full-duplex algorithms) that worked fine for narrowband speech have to be totally redesigned, retested, and re-integrated to deliver clear, trouble-free speech.
Look for Part 2 of this 3 part series tomorrow.