y devices with sound capabilities add to your listening pleasure because they provide 3-D sound effects for your Rebel Assault space battles and multimedia applications.
For this roundup, we tested 10 products (eight internal and two external) that bring us closer to the vision of integrating telephones with computers. These
telephony devices
have full-duplex speakers and microphones for hands-free telephone conversations (you can use a headset instead of the speakers if you want privacy). The best telephony cards we tested are total out-of-box solutions with easy-to-use telecommunications management software. Software telephony utilitie
s commonly bundled with the telephony devices include multiple- mailbox voice mail, fax reception and fax broadcasting to and from multiple users, and paging services.
To evaluate the cards, we ran performance tests that measure each modem's data-throughput rate. (All of them have at least 28.8-Kbps modems.) The speed of the internal modem, after all, is the main performance issue for telephony cards. We also put heavy emphasis on features and usability. We wanted to make sure the internal cards and external boxes were easy to install and use. We found the self-configuring plug-and-play devices the easiest to install because you don't have to fuss with IRQ/DMA jumpers or switches.
Dial 33.6 for Faster Throughput
The fastest modem in our testbed is the US Robotics Sportster Voice 28.8 Faxmodem PVM, which (despite its misleading name) is the only telephony card we tested that supports the latest V.34 protocol for transmission speeds of 33.6 Kbps. (Remember that to get the higher s
peed, you need a 33.6-Kbps modem at both ends of the connection.) The new protocol upstages the predominant 28.8-Kbps modem baud rate by using a more advanced coding mechanism for sending and receiving data. You can boost DSP-based modems that have 28.8-Kbps data pumps to the 33.6-Kbps baud rate with a flash ROM upgrade.
US Robotics' Sportster proved to be consistently the best performer in our gauntlet of file transfer benchmarks, albeit not really 16 percent faster than the closest 28.8-Kbps modems: Hayes Microcomputer Products' Accura 28.8, Best Data Products' Smart One 2834VLX External Modem, and Aztech Labs' AT3300 Audio Telephony.
Calling SOHO Users
File transfer performance is certainly important, but the telephony devices we tested are more than just glorified modems. Their many telephony features can make your small office sound like a big corporation's front desk when someone calls you. They come with professional-sounding prerecorded greetings, and you can set u
p multiple mailboxes for different users at your location. We recommend you keep voice-quality settings as low as possible to minimize the amount of space needed to store messages; voice-mail messages are disk hogs. Fortunately, most voice-mail software lets you set parameters for message length and mailbox size.
For long-distance access, you can dial in to check your messages and even have them forwarded to remote locations; most telephony devices will even page you when they receive messages and faxes. Callers can also get nearly instant information about your business by accessing fax-on-demand services when you're not in the office to take their calls. Password ID lets only authorized users dial into their mailboxes, and caller ID lets you screen annoying callers. You can view incoming faxes on-screen before printing them.
The vendors bundle a demo copy of voice-over-the-Internet software like Netspeak's WebPhone or VocalTec's Internet Phone and utilize Digital Simultaneous Voice and Data (DS
VD) or Alternating Voice and Data (AVD) technology. Modem applications can typically run at 19.2-Kbps data rates while in DSVD mode. On-line game combatants and technical support people can use DSVD to keep their conversation going without disconnecting the voice channel to connect a data channel. For on-line services, the vendors provide software for CompuServe, America Online, and the Imagination Network. They also toss in a Web browser.
Most of the telephony cards have sound capabilities, but you won't need that if you already have a dependable Sound Blaster Pro-compatible card in your system. Having a sound chip on the card isn't really necessary for telephony applications, but it's a nice bonus if you have just a mono speaker. If you are happy with your PC's sound, then you can save some money with an inexpensive "nonsound" telephony device like Best Data's Smart One 2834VLX External Modem ($209) or Connectware's PhoneWorks 28.8 ($229).
C
ontributors
Jim Kane, Project Manager/NSTL
Dorothy Hudson, Project Manager/NSTL
John McDonough, Technical Writer/NSTL
Maggi Bender, Technical Analyst/NSTL
Helen Holzbaur, Manager, Licensees and Methodologies/NSTL
Susan Colwell, Technical Editor/BYTE
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10 Multifunction Telephony Boards
