Conference calling

In the last ten years, voice conferencing equipment has shrunk from a whole rack, to a single 2U unit. Chris Fitzsimmons talks to vendors about where we’re at now, what the future holds, and how the integrator can still add value whilst the part count dwindles.

The last time we looked at this subject, I listed a few reasons that you might want to engage in a remote conference rather than travel. They included environmental concerns, security fears as well as a nod to cost efficiency. 15 months later, and the picture has changed somewhat. Top of that list of reasons is now cost savings.

Fortunately, not only does a remote call allow your to hold meetings effectively, and with ever improving sound quality, the cost to them of implementing the solution is coming down and down. What was once a one rack solution can now be as small as a single box.

The second generation of products from the major players has now been in the wild for at least a year, so they’ve had a chance to bed in, and we’re beginning to see firmware updates and feature additions as the user-base becomes more familiar with the new ranges.

Polycom announced SoundStructure in the middle of 2007 as a successor to its Vortex solution. The latest iteration of SoundStructure is the C-Series, which incorporates Polycom’s HD Voice technology – its name for G.722 encoding, an ITU (international telecommunication union) standard for digital audio. It delivers everything in the 7kHz to 22kHz frequency range, offering a much clearer voice conferencing experience.

Patricia Finlayson, Polycom’s marketing manager for installed voice in EMEA, explained the benefits of HD Voice. “In business conversations, especially when you are talking to someone whose first language isn’t the same as yours, it can be quite difficult to communicate anyway. But if you don’t hear every nuance, you can miss out on very important things. It’s a productivity thing as well as comprehension.”

SoundStructure also features feedback elimination, acoustic echo cancellation on each input channel, and dynamic noise suppression.

“We really went back to the drawing board [with C-series] and asked what we could do better if we started from scratch. We developed the OBAM (one big audio matrix) concept, which essentially means that when you connect more than one of these boxes together, the software just sees it as one larger one. It starts at 32x32 and goes all the way up to 128x128 which is the theoretical limit right now.”

In the curious case of the ever-shrinking conference solution, one of the prime suspects must surely be ClearOne. Converge Pro, the replacement to its XAP series has recently had its firmware updated and a couple of new models. I caught up with Scott Woolley, director of product marketing for professional audio products.

“ConvergePro 880TA is our latest product from the range. It’s an 8-channel automatic microphone mixer with routing and signal processing, and we have incorporated four 35-Watt amplifiers into it.”

This essentially allows you to drive four channels of ceiling speakers or low-powered wall monitors direct from the unit. Integrating the amplifiers gives you several advantages according to Woolley:

“The advantages of having the amplifiers in the box are firstly, ease of installation – there’s no need to connect the DSP unit to an amplifier. Secondly, lower cost – parts count and labour costs are reduced. Then, and this is actually the primary reason that we did it, when we have an outboard amplifier, we can’t watch or monitor the signal coming out of it. We can only monitor what goes out of our box. If a level changes or something occurs in the amplifier, our hardware may not be aware of it, and because we use an adaptive technology it may take a little longer for it to figure it out.

“The technical reason for integration is that we can watch what is coming out of the amplifier and pass that information back to the adaptive technology in the echo canceller or other filters and it leads to better sound.

“The other side of this is that all of our systems are remotely manageable over an Ethernet connection, and now that extends to the amplifier as well because it’s built into the box. You can adjust the signal processing and the amplifier all through the same interface.”

But surely if everything’s integrated that leaves the integrator out in the cold somewhat. Reduced parts counts means lower equipment costs for the customer, which is good, but potentially less profit for the installer. Not so, argues Woolley, you can’t downsize physics.

“The integrator’s expertise can’t be engineered out with products. You still need someone to set up a room, where do the microphones go? Where should the loudspeakers be placed? The physics of room acoustics, and the configuration of gates and compressors are still essentials of conferencing. Then there’s the tuning of the filters – even if we are using automatic AEC with narrow band filters, we still need to do broadband EQ’ing of these systems.”

ClearOne also recently upgraded its firmware for ConvergePro, this was partly to add functionality but also to incorporate support for the new 880TA model into its conferencing family. The 2.x release of the firmware increases the bandwidth on ConvergePro’s expansion bus, and also the number of gating groups.

Moving forward, product development within the lifecycle of the new range, will certainly focus on things like Firmware updates. AEC and feedback elimination algorithms are software functions that can simply be uploaded to the units, provided they are within the processing capabilities of the DSP chips.

Other improvements have also been made in v2.x: “We improved our algorithms for automatic microphone activation, trying to eliminate false activations such as pens tapping on desks, or coughing etc.”

Biamp has taken the rack size reduction concept even further. In June 2008, the company launched it’s Revolution campaing, promising integrators freedom from the rack, get past the marketing and there’s an exciting concept. For a number of years, you’ve been able to tailor its AudiFLEX system to your needs.

Buy a FLEX frame, choose some input and output option cards and plug them in. This concept was expanded much further, however with the addition of the PA-2 expansion cards. These are dual-channel amplifier cards, which can be run in mono-bridged mode for a total of 60W each. They can drive 4,6 or 8-Ohm speakers. Of further interest at the new AEC-2HD cards, which provide two channels of AEC a-piece, along with the TI-2 telephone interface cards, which allow direction to any standard analogue telephone lines. Alternatively for VoIP systems, there are the VoIP-2 input cards allowing digital telephony to be integrated into the units.

The combination of all these leads to a single, 2U unit, which contains telephone interface, amplification, AEC and other DSP functions and expandable input options. Better yet the modularity of the system means you can have exactly what you need in the frame, without paying for what you don’t need.

The system can then be managed via either a third party control solution or by Biamp’s own daVinci software programme running on a touch-screen PC. The only thing that Biamp don’t currently offer is the loudspeakers and the conference microphone itself although one might speculate that the arrival in 2008 of its first paging microphone, and I don’t speak with any inside knowledge here, could herald the arrival of other input options.

The other two big players do however. Polycom has now integrated its HD Voice technology into its SoundStation range of IP desktop endpoints. ClearOne’s latest conference phones, the Chat-series was recently joined by the Chat-170, which is a customised version of the Chat-150 designed specially to work with Microsoft’s Office Communicator 2007 suite.

As we’ve noted before, Yamaha commercial audio takes a slightly different approach. It has integrated everything into one unit with its PJP (project phone) range. However, they are aimed as a slight different proposition to the systems discussed above. Rather than being designed to work as part of a large room installation with ceiling speakers etc, they are stand alone, pure VoIP appliances designed to connect via a PC to the rest of the participants. Despite this they still carry 3-channels of AEC, as well as background noise cancellation.

No one is talking too much about revolutionary product announcements at the moment. Whilst 2007 and 2008 saw significant new ranges hitting the streets, this year is likely to be all about refinement and feedback from the customer. Installations of such products tend to have longish life times, up to ten years, and vendors risk frustrating existing client bases by refreshing things too often. Expect however, to see considerable effort expended on refining the software and the algorithms that are the real heart of modern conferencing systems.

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