Gentner Audio Perfect 800 User manual

Perfect Communication through Technology, Service, and Education.
TM
Installation & Operations Manual
Audio Perfect™ 800
AP800

Audio Perfect™ 800 Installation and Operations Manual
Gentner Part No. 800-150-001
Fe ruary 2000 (Rev. 1.1)
©2000 by Gentner Communications Corporation. All rights reserved. No part of this manual may be reproduced in
any form or by any means without written permission from Gentner Communications Corporation. Printed in the
nited States of America. Gentner Communications Corporation reserves specification privileges. Information in
this manual is subject to change without notice.
Manual Development: Bill Kilpack, Gerry Carpenter
Artwork and IIlustrations: Jim Wright, Bill Kilpack, Don Semon
This equipment complies with the requirements of the European guidelines:
89/336/EEC "Electromagnetic Compatibility"
73/23/EEC "Electrical operating material for use within specific voltage limits"
98/482/EC "Single terminal connection to the public switched telephone network."
Conformity of the equipment with the above guidelines is attested by the CE mark.

TECHNICAL SUPPORT: 1.800.283.5936 (USA) OR 1.801.974.3760
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Warranty Registration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Features and Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Product Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
2. Installation and Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Front Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Rear Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
G-Link Networking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Distributed Echo CancellationTM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Before You Install . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Room Planning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Microphone Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Microphone Placement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Power Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Windows Requirements (optional) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
PC Hardware Requirements (optional) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Auxiliary Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Equipment Placement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Environmental Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Completed Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Step 1 — Back Panel Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Step 2 — G-Link Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Step 3 — Device ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Step 4 — Mixer Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
LCD Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Menu Trees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
System Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Input Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Output Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Routing Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Meter Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Volume Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Muting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
able of Content
T

TECHNICAL SUPPORT: 1.800.283.5936 (USA) OR 1.801.974.3760
TABLE OF CONTENTS
2
3. Appendices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Appendix A
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Appendix B
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
FCC Part 15 Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
Appendix C
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Appendix D
Connector Pinouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Appendix E
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
Appendix F
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
Appendix G
Serial Port Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
Appendix H
Worksheets and Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71
List of Figures
Figure 1. Equipment Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Figure 2. AP800 Front Panel Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Figure 3. AP800 Rear Panel Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Figure 4. Room Acoustics Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Figure 5. Conference Room Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Figure 6. Microphone Isolation Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Figure 7. Completed AP800 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Figure 8. AP800 Power Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Figure 9. AP800 Rear Panel Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Figure 10. Phoenix Three Terminal Push-on Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Figure 11. Phoenix Connector Block, Output A–D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Figure 12. Phoenix Connector Block, Input A–D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Figure 13. Phoenix Connector Block, Output 1–8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Figure 14. Phoenix Connector Block, Mic 1–8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Figure 15. AP800 COM Port Connector (RS232) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Figure 16. AP800 Control/Status A and B DB25 Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Figure 17. AP800 G-Link Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Figure 18. G-Link Network Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Figure 19. Multiple AP Systems Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Figure 20. LCD Menu Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Figure 21. System-level LCD Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Figure 22. Default Programming Worksheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Figure 23. Gate Parameters LCD Submenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Figure 24. PA Adaptive Mode Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Figure 25. Off Attenuation Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28

TECHNICAL SUPPORT: 1.800.283.5936 (USA) OR 1.801.974.3760
TABLE OF CONTENTS 3
Figure 26. Hold time Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Figure 27. Decay Rate Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Figure 28. RS232 Parameters LCD Submenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Figure 29. Mic Inputs 1–8 Parameters LCD Submenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Figure 30. Adaptive Ambient Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Figure 31. Inputs A–D Parameters LCD Submenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Figure 32. Outputs Parameters LCD Submenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Figure 33. Default Routing Matrix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Figure 34. Routing Parameters LCD Submenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Figure 35. Echo Cancellation Setup Default Matrix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Figure 36. Master nit EC Example Matrix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Figure 37. Slave- nit EC Example Matrix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Figure 38. Meter Parameters LCD Submenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Figure 39. AP800 Teleconferencing Application Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Figure 40. AP800 Distance-learning Application Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
Figure 41. AP800 Courtroom Application Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
Figure 42. AP800 Convention Center Application Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
Figure 43. Routing Matrix Worksheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71
Figure 44. Programming Worksheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
Figure 45. AP800 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73
List of Ta les
Table 1. RS232 COM DCE Port Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Table 2. Control/Status A Port Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Table 3. Control/Status B Port Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Table 4. AP800 Serial Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38

TECHNICAL SUPPORT: 1.800.283.5936 (USA) OR 1.801.974.3760
TABLE OF CONTENTS
4

TECHNICAL SUPPORT: 1.800.283.5936 (USA) OR 1.801.974.3760
1
Congratulations on purchasing the Audio PerfectTM 800 (AP800)
distributed echo cancelling, audio processing, microphone mixing
matrix. Communication media such as voice mail, the Internet,
conference calling, videoconferencing and electronic presentation are
driving the demand for better audio-communication technologies. At
the same time, organizations are looking for ways to decrease cost and
complexity while increasing efficiency and productivity.
The Audio PerfectTM product line was developed in response to these
needs. Audio is critical to electronic meetings. This eight-channel, PC-
controllable microphone mixer and echo canceller is a first in the
audioconferencing industry. In a single box, Distributed Echo
CancellationTM is provided for individual microphone channels, while
allowing the easiest interconnection with the rest of its product family.
This network-based interconnectivity allows for multiple AP800s to be
connected and controlled as a single unit. p to eight AP800s can be
networked, allowing microphone coverage in applications requiring up
to 64 mics. The AP800 is a perfect solution for applications in
audioconferencing, videoconferencing, distance learning, board rooms,
conference rooms, teletraining, telemedicine, courtrooms and
hotel/convention centers.
The AP800 contains commonly requested features such as an RS232
connection for PC control or remote control via custom remote
controllers, local or remote PC setup and diagnostics, logic outputs,
front-panel passcode protection and user-programmable gated
Introduction
Audio Perfect 800
INTRODUCTION • A DIO PERFECT 800 5

TECHNICAL SUPPORT: 1.800.283.5936 (USA) OR 1.801.974.3760
INTRODUCTION • WARRANTY REGISTRATION
6
microphone operation. The latter allows you to address microphones
individually choosing how many you wish to gate or not to gate; when
coupled with Distributed Echo CancellationTM for each microphone
channel and automatic gain control (AGC) for each input, the AP800
can work in nearly any application. This manual explains how to install,
set up and operate your AP800. It also provides instructions on how to
improve room acoustics and resolve minor technical problems, should
any arise.
If you need additional information on how to install, set up or operate
your system, please contact Gentner Communications Corporation at
the location noted below. We welcome and encourage your comments
so we can continue to improve our products and serve your
conferencing needs.
Gentner Communications Corporation
1825 Research Way
Salt Lake City, tah 84119
TEL: Worldwide 801.975.7200 In .S.A. 800.945.7730
FAX: Worldwide 801.977.0087 In .S.A. 800.933.5107
FAX-On-Demand 24-Hour Information line 800.695.8110
FAX-On-Demand International Line 801.974.3661
Worldwide Web Page @ http://www.gentner.com
[e-mail]
Warranty Registration
Please register your Audio Perfect™ product online by visiting Gentner
Technical Support at the World Wide Web address listed above. When
your product is properly registered, Gentner Communications will be
able to serve you better should you require technical assistance or
desire to receive upgrades, new product information, etc.

TECHNICAL SUPPORT: 1.800.283.5936 (USA) OR 1.801.974.3760
INTRODUCTION • FEAT RES AND BENEFITS 7
Features and
Benefits
Distributed Echo Cancellation™ technology; each microphone has
its own echo canceller for a total of eight echo cancellers per unit
Plug-and-play echo cancellation
100 percent digital signal processing (DSP)
Simultaneous direct connection to several video codecs and
telephone lines (using AP10 Telephone Interfaces)
Two internal submixing buses used for mixing and level control in
sound-reinforcement systems
12 x 12 matrix mixer
Two internal submixing buses used for mixing and level control in
sound-reinforcement systems
Twelve line output channels expandable to 96; any of the 12 input
channels can be mixed to any of the 12 outputs on a given unit; all
output levels are adjustable and can be instantly muted
Eight-channel automatic microphone mixer with four line inputs
expandable to 64 mic inputs and 32 line inputs interconnected
All automatic microphone functions and operating modes operate
across expanded units
Input gain, audio processing, equalization, muting, and automatic
mixer programmable per input channel
Expandable using a high- speed digital network bus; a total of eight
AP800s and 16 AP10s can be interconnected
All G-Linked devices can be accessed, controlled, and programmed
via a single RS232 connection
Program, operate and perform diagnostics from the front panel, a
connected PC (direct or via modem) or any other type of serial
remote-control device
Six programmable presets for instant configuration changes
Lockout front-panel access for security

TECHNICAL SUPPORT: 1.800.283.5936 (USA) OR 1.801.974.3760
INTRODUCTION • APPLICATIONS
8
Applications
The AP800 contains many unique features that make the AP800 easier
to set up and use. Specific user programming capabilities tailor-make
AP800 functionality to suit almost any application, including
audioconferencing, videoconferencing, distance learning, boardrooms,
conference rooms, teletraining, telemedicine, courtrooms, and
hotel/convention centers.
For block diagrams of AP800 applications, see Appendix E (page 45).
Product Description
The AP800 performs a variety of complex, integrated audio functions,
all implemented using digital signal processors (DSPs). This product
line was not designed as a generic solution for a wide variety of uses.
Instead, it was designed to meet the specific audio needs of a limited
number of applications. By pursuing these vertical applications, the
AP800 has been stripped of features and functions that would result in
higher cost, complexity and unreliability.
In its most simple form, the AP800 is a microphone mixing matrix. As
such, all microphone-mixing parameters can be customized and any
input or combination of inputs can be routed to any output, allowing
flexibility in fitting different applications and customer requirements.
Adjustments in routing, level and all other functions can be made at any
time in one of three ways: front-panel programming, presets activated
through a closure on the rear panel, and RS232 serial interface.
However, the AP800 is much more than a simple microphone-mixing
matrix. The AP800 operates on four basic principles: gating micro-
phones, Distributed Echo CancellationTM , decisions for each micro-
phone, and network architecture. The AP800 gates microphones on/off
when the sound within a microphone’s acceptance pattern reaches a
certain level. The AP800 provides Distributed Echo Cancellation™
which makes decisions for each microphone individually, based on
each microphone’s specific conditions. The AP800 functions with a
network architecture which allows up to eight AP800s and up to 16
AP10s to be linked via the G-Link and operate as a single unit.
Each microphone reacts independently, observing its own ambient
levels and making decisions based on its individual environment. Thus,
a microphone located in a highly reverberant part of a conference room
is able to compensate for the changes in its own area. The AP800
monitors audio levels at each microphone and reduces the mixing level
for microphones not in use and/or eliminates echo. This improves the
audio quality for the listener and decreases the possibility of feedback.