| I'm sure you've all seen it. You know. It's that | | | | full-duplex equipment. They allow communication |
| triangular spaceship on the table in the conference | | | | to occur simultaneously in both directions. In fact |
| room. During that important meeting it | | | | the built-in speakerphones in home and business |
| mysteriously turns on. You talk to it, and voices | | | | desk phones are typically full-duplex. These built-in |
| talk back to you. You like to use it. Conversations | | | | speakerphones do allow both parties to speak at |
| are clear. Words are clear, and nothing is lost in | | | | the same time, but they must alternate the |
| translation. Okay. I've been reading too much | | | | microphone and speaker activity to diminish |
| Michael Crichton. | | | | feedback. Just think, if your voice was coming out |
| Desktop and tabletop conference speakerphones | | | | of a speaker and the microphone was active and |
| are a necessity in most small businesses. When | | | | picking it up, you would start a positive feedback |
| multiple parties need to be heard and need to | | | | loop that could blow your ears out. Consequently, |
| listen, there is no better solution. The built-in | | | | when the speaker is active, the microphone must |
| speakerphone on the typical desk telephone won't | | | | deactivate and vice-versa. This is the main cause |
| suffice. They are useful in most one-on-one | | | | of clipping. |
| conversations, but if you walk further from the | | | | How do stand-alone tabletop conference |
| phone or have two or more people trying to | | | | speakerphones solve this problem? Current |
| speak, problems arise. Most users of complain | | | | conference room grade speakerphones use digital |
| about having to talk loudly or directly into the | | | | signal processing (DSP) algorithms to subtract |
| speakerphone, and commonly, "clipping" occurs. | | | | incoming audio speaker signals from outgoing |
| You may have experienced this when your first | | | | microphone signals. This process allows the |
| word or syllable is cut out as the party on the far | | | | speaker and microphone to be active at the |
| end begins to speak. | | | | same time and solves the problem of clipping. It's |
| So, what's the problem? Well, we've come a long | | | | really black magic to most, but it works great. |
| way from the days of half-duplex communications | | | | They also include high quality speakers and |
| equipment. Walkie-talkies are a good example. | | | | sensitive microphones arranged in radial patterns |
| When you're done speaking into the microphone | | | | to provide complete room coverage. |
| of a walkie-talkie, you let the other person know | | | | Many units are sold used and new and have a |
| by saying, "over," and then they know it is their | | | | wide price range. For as little as $149, you can |
| turn to speak. This type of communication must | | | | purchase a unit that can handle small to medium |
| occur because half-duplex equipment only has a | | | | size applications for up to a dozen users. On the |
| one-way talk path. Only one party can speak at a | | | | high-end, $499 to $799, you can purchase |
| time. | | | | wireless, proprietary digital, IP, and wide-band |
| Today's home phones and cell phones are | | | | audio units. |