User manual BIAMP VOICECRAFTER

[. . . ] ADVANTAGE® VOICECRAFTER and VOICECRAFTER Plus Acoustic Echo Cancellers Operation Manual ® Biamp Systems, 10074 S. W. (503) 641-7287 http://www. biamp. com Feb 1/00 an affiliate of Rauland Borg Corp. blankVOICECRAFTER and VOICECRAFTER Plus TABLE OF CONTENTS Front & Rear Panel Features Software Control TTC Control Configuration Calibration Option Connecting External Equipment RS232 Applications Troubleshooting Third-party Control Specifications & Block Diagram Warranty pgs. 21 INTRODUCTION ADVANTAGE® VOICECRAFTER and VOICECRAFTER Plus are tamper proof Acoustic Echo Cancellers, which provide full-duplex speech between 2 or more locations in video or teleconferencing applications. VOICECRAFTER is a DSP based device and is easily programmed via Windows® 95/98/NT software. [. . . ] Enable the internal white noise generator, click on the Noise box in the Main Output section (enabled is checked, disabled is unchecked, white noise sounds like hiss). The Receive LED on the VOICECRAFTER will be green when white noise is being generated. Adjust the amplifier level so that 72dB (`A' weighted setting) of sound pressure is measured approximately 3 Inches (7. 5 cm) in front of the microphone. (There is a screwdriver adjusted level pot on the rear panel of the VOICECRAFTER that will provide more gain if needed, but having the level pot set to the lowest position will still allow audio to pass. ) Hint: If a sound pressure level meter is not available do not enable the white noise, instead have someone speak into the mic at normal speech levels. Adjust the trim control on the rear panel of the VOICECRAFTER, and/or the external mixer output, so that the Channel 2 peak LED is lit with the white noise on (or speech if SPL meter isn't available), then back the trim control off until the trim LED goes off. Look in the Averages section of the Control Software and view the EC_Si section. Adjust the Channel 2 Gain (VOICECRAFTER software) so that the average EC_Si is approximately -20dB. Turn on the white noise again, measure the AERL in the Averages section of the Control Software. Using the pull-down menu set the Target AERL to the same value as measured. Click on the Config button at the bottom of the train screen to begin a Configuration Train Cycle. The VOICECRAFTER will use white noise to perform the Configuration Train Cycle. Hint: If a SPL meter is not available, adjust the speaker level for a comfortable listening level in the room (still using white noise). Hint: If the measured AERL is not between +2dB and +20dB, adjust the level of the amplifier either up or down. Increasing amplifier level will lower AERL, and decreasing amplifier level will increase AERL. Training results will be displayed in the training menu by clicking the `OK' button on the `Training Done' screen. Once acceptable training responses have been achieved (AERL within +/-2dB of set target, and ERLE >7 see hints below) set AutoAdaptation to Fully Enabled, store the resulting configuration by clicking on the Store button followed by the desired memory location on the `popup' menu. The VOICECRAFTER will power up into the mode stored into the Preset 1 location. Presets 2~5 can be used to store room configurations for different rooms (roll about applications), or different room configurations where mics and speakers are moved around. Hint: If training results are not achieved adjust AERL target +/-2dB depending on direction of white noise adjustment during Configuration train. Example: During a train, if white increases, increase AERL target by 2dB. Retrain the VOICECRAFTER after any AERL target changes Hint: For most rooms the ERLE should be 8dB or greater. A low ERLE in a highly reflective room means that the echo canceller may not be able to adapt quickly to changes in the room. [. . . ] To be certain of the number of devices that may be connected to the line, as determined by the total RENs, contact the telephone company to determine the maximum REN for the calling area. This equipment cannot be used on the telephone company-provided coin service. If this equipment causes harm to the telephone network, the telephone company will notify you in advance that temporary discontinuance of service may be required. If advance notice is not practical, the telephone company will notify the customer as soon as possible. [. . . ]