With a speakerphone we can talk, discuss, listen to the far end side with hands-free. A conference speakerphone allows both ends to talk at the same time, and is why it is the most common type found in conference rooms and other business environments.

To test an CONFERENCE SPEAKERPHONE you will want to have two phones, the one you’re testing and a high-quality handset phone. If you’re testing over VoIP this handset should also be HD Voice-capable.

Put the conference speakerphone you’re testing in the room in which it will be used or somewhere similar. Put the second phone in another room and be sure the two can’t hear each other at all when a call is hung up, as even a whisper of sound heard directly from the other end can mess up the tests.

Here are the steps:
Check that you can place a call between the two and that it sounds okay to the casual listener. If this is an HD VoIP link, check that the call is actually connecting in HD.

A true conference speakerphone goes through a period of convergence at the beginning of a call. During this time it is analyzing the acoustic environment as well as the impulse response of the telephone line in order to cancel all echoes before they occur. Start the call by having each end talk alone, in turn. The near end should do a clear, slow count to ten, and then let the far end do the same. Then repeat both counts.

Now that the conference speakerphone is converged, let the far end talk and see how that sounds. Is it clear and undistorted? Does it sound natural? Turn up the loudness all the way and ask the far end to talk softly, then loudly. Does it still sound clear and unclipped? Any distortion is an indication that the speaker or amplifier is not designed with enough latitude to handle the wide range of sound encountered in normal conversations, while clipping indicates that the conference speakerphone is going to have serious trouble when a real conversation begins.

From a distance of about three feet, talk normally. How do you sound to the far end? Is there a lot of room noise, indicating that the microphones are not good at picking your voice out of the sound field? Does your voice sound muffled because room reverberation is muddying the sound, or is it clear? Now talk loudly about one foot from the conference speakerphone. Is it undistorted at the far end? Move away as far as possible, and speak. Can you still be heard? The better ones can clearly pick up a talker 10-15 feet away when speaking in a soft voice, so this should be your standard.

Full-duplex, near end and far end. As with the one-way tests, these will be ranked separately. The difference is that we’ll perform them at the same time, because that’s what full-duplex is: both ends speaking at once. What you’re listening for is the tendency of many conference speakerphone’s to let one direction swamp the other.

If they are not carefully designed and built, this can easily happen because good full-duplex is a sensitive balancing act. However, it’s not hard to make an CONFERENCE SPEAKERPHONE that blocks out one direction while letting the other pass through. Further, they are often designed to favor the received signal, so it sounds to the owner as if the conversation is unobstructed. It’s harder to build one that works well the other way by clearly picking up your voice, but that direction is most important since it’s often your customer, boss or partner that hears what the phone is doing to your voice.

Here’s how we’ll listen for that. Sit about three feet from the speakerphone and count out loud in a slow, steady cadence from one to ten. At the same time have the person at the other end recite the alphabet from A through J. Synchronize your speech with hers, so that you are saying “A” at the same moment she is saying “one” and you’re talking over each other. Did you hear every letter? At the same time, did she hear every digit? Did it start clipping or cutting out after you got past the first few digits? Some conference speakerphone’s are good for a few seconds and then get choppy.

If that worked well, try more real-world situations. Move six feet away from the conference speakerphone microphone and repeat. Can she still hear you when you both talk at once? How about at 10 feet? This becomes a challenging test because to the speakerphone your own voice is now only one-hundredth as loud as the voice on the loudspeaker, and yet it still needs to pick out only your voice and send it back. What’s more, it has to do this while compensating for all of the echoes, reverberation and noises in the room.

If the CONFERENCE SPEAKERPHONE passes all these tests, congratulations – you’re choosing a good one.

More at meeteasy.com.hk