Vortex EF2211/EF2210 Reference Manual
VORTEX EF2211/EF2210 REFERENCE MANUAL Introduction....................................................................................................2 Features and Benefits ............................................................................................. 3 Pre-Installation...............................................................................................4 EF2211/EF2210 Front and Rear Panels................................................................ 5 Installation ............
INTRODUCTION INTRODUCTION Welcome Congratulations on your purchase of the Vortex EF2211/EF2210! How to Use This Manual This is a reference manual for your EF2211/EF2210. Information specific to the EF2211 or EF2210 will be noted as such. The major difference between the EF2211 and the EF2210 is that the EF2210 does not have a phone interface. This manual is structured to provide the information you need quickly and conveniently.
INTRODUCTION Product Registration Please take a moment to fill out and return your registration card. This information will help us to provide you with better customer support and will allow us to notify you with updated product features and software. FEATURES AND BENEFITS • • • • • • • • • • © Polycom, Inc.
PRE-INSTALLATION PRE-INSTALLATION What’s Included The Vortex EF2211/EF2210 product package includes the following items: • • • • • • • • • • Vortex EF2211/EF2210 Reference Manual Vortex EF2211/EF2210 External power supply Cat 5 cable for EF Bus Telephone cable (NOT included with the EF2210) Rack mount screws (4) 3.
PRE-INSTALLATION EF2211/EF2210 FRONT AND REAR PANELS EF2211 ORTEX DOWN UP HOME METER -20 -12 -7 -3 1 2 4 5 6 7 PHONE CONNECT 3 9 20 dB 8* 9 OUTPUTS RS-232 PIN 2: TXD, PIN 3: RXD, PIN 5: GROUND, PIN 7: CTS, PIN 8: RTS EF BUS IN INPUT 3 0 +5, +/-15 VDC 1 A B 1 INPUTS A B SPEAKER REMOTE CONTROL OUTPUT PHONE EF BUS OUT 10* 11* 12 13 LINE VORTEX EF2211 RS-232 14 15 16 17* 19 18 Figure 2. EF2211/EF2210 Front and Rear Panels 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.
INSTALLATION INSTALLATION This equipment is intended to only be installed by qualified service personnel. The equipment shall be connected to a socket-outlet that provides a protective earthing connection. North American Requirement CAUTION-To reduce the risk of fire, use only No. 26 AWG or larger telecommunication line cord. MOUNTING THE EF2211/EF2210 The EF2211/EF2210 can be mounted in a rack enclosure using four large screws (1032x1/2”) included with the unit.
INSTALLATION Typical EF2211/ EF2210 Connections The EF2211/EF2210 will typically be connected to other equipment in a single room setup as shown below in Figure 3 and Figure 4. Mic In Amp Out Far In Far Out Prgm In Rec Out Polycom Video CODEC Line In Line Out Vortex® EF2211 Spk Out Phone Line EFBus In EFBus Out PSTN Figure 3. Block diagram of typical EF2211/EF2210 connections: a single room using one device. NOTE: The phone interface is not available on the EF2210.
INSTALLATION • • • • • • input accepts 3.5 mm terminal block connectors. See “Connector Pinouts” on page 52 for pinouts of the terminal block connectors. Connect SPEAKER OUTPUT to loudspeaker or AMP OUTPUT to the room amplifier. If RS-232 remote control is desired, connect the RS-232 REMOTE CONTROL port of the EF2211/EF2210 to the remote control device, such as an RS-232 interface to a touch panel or a COM port on a personal computer. On the EF2211, connect the LINE RJ11 jack to an analog telephone line.
INSTALLATION 5. 6. Terminating the EF2211/EF2210 Connect another Cat-5 cable between the EF BUS OUT of the second device and the EF BUS IN of the third device, and so on. Power on all units at the same time. The EF2211/EF2210 is self-terminating so its EF Bus does NOT need to be terminated. However, if you are linking the EF2211/EF2210 to EF2280s, terminate the EF Bus link.
INSTALLATION PRESET (or whichever preset you want to come up after power up). The unit will need to be configured for your system.
INSTALLATION PROGRAM PARAMETERS FACTORY DEFAULT PRESET VALUE Entry and Exit Tone Enable On PHONE INPUT (INPUT T), EF2211 ONLY Automatic Gain Control (AGC) On AGC Maximum 12 dB AGC Minimum -6 dB AGC Rate 1 dB/s Phone Input Gain 0 dB Mute Off Noise Cancellation On Noise Cancellation Level 5 dB Line Echo Cancellation On Dynamics Processing On Filtering Off PHONE OUTPUT (OUTPUT T), EF2211 ONLY Presets and Multiple Vortex Devices Mute Off Phone Output Gain 0 dB Dynamics Processing
INSTALLATION close to the piece of equipment as possible. A 0 dB nominal level is a good standard signal level. For example, a consumer VCR will probably generate a -8 dBu level. As soon as the VCR signal arrives at an input with some gain control, the input gain should be adjusted so that you get a 0 dB level, i.e. adding 8 dB of gain. Check Levels to the Codec Configure the matrix mixer output to the codec input.
INSTALLATION 3. OR adjust the placement of the microphone relative to the loudspeaker. Room Gain Meter Read Room Gain from here Figure 6. Room Gain Meter on the Diagnostics page of the Conference Composer control software. Configure Program Audio Sources © Polycom, Inc. Set the gain on the matrix mixer input from the program audio source so that program audio is played into the room at a level similar to that of speech from the remote site.
INTEGRATING THE UNIT INTO YOUR SYSTEM INTEGRATING THE UNIT INTO YOUR SYSTEM Operating the EF2211/EF2210 The EF2211/EF2210 can be operated in two ways: through the LCD menu on the front panel or through RS-232. For control via RS-232, please refer to the EF2211/ EF2210 Programming Guide, which includes programming tips as well as the EF2211/EF2210 RS-232 commands. For operation using the PC control software, Conference Composer, please refer to the Conference Composer User Guide.
INTEGRATING THE UNIT INTO YOUR SYSTEM Fine tune the Input Gain using the Automatic Gain Control (AGC) meter on Conference Composer Software. In the Conference Composer Software, go to the DIAGNOSTICS page. Watch the meter labelled AGC while someone is talking into the particular channel that you are adjusting. Watch the number in the box at the bottom of the AGC meter (See Figure 7 below). This is the amount of gain that the AGC is applying. The goal is to have the AGC meter on average staying around 0.
INTEGRATING an average level of 0 dB THE UNIT INTO YOUR SYSTEM You’ve set the Input Gain to a good level! Table 1: How to set the Input Gain using the AGC meter on the Conference Composer Diagnostics page. Customize Setting for Your Particular Application The following sections will describe customizing parameters on the EF2211/EF2210 for your particular application if you are not using Preset 0.
INTEGRATING THE UNIT INTO YOUR SYSTEM ECHO CANCELLER REFERENCE FOR MULTIPLE VORTEX DEVICES In a system with multiple devices, we recommend that one device be designated as the unit that provides the EF bus reference for the acoustic echo cancellers. This unit takes its reference signals and places it on the EF bus. All other units that are linked together may use the EF bus reference as the reference for their echo canceller, or they can use their own internal reference(s).
INTEGRATING THE UNIT INTO YOUR SYSTEM Figure 10. Matrix page of linked devices If far end audio and program audio sources are on several Vortex devices. 1. 2. Bus each far end audio and program audio source to each device. Do this by assigning each signal input to either the W, X, Y or Z bus. Assign an echo canceller reference on each device that will include all far end audio and program audio sources. CONFIGURE THE AUTOMATIC MICROPHONE MIXER The EF2211/EF2210 contains one automatic microphone mixer.
INTEGRATING THE UNIT INTO YOUR SYSTEM Bias, Off Attenuation, Threshold Type, Gating Mode, Adaptive Threshold, Manual Threshold, and Gate Priority. Signal Level Channel turns on when signal level is above Adaptive Threshold DECAY TIME Channel ON ADAPTIVE THRESHOLD Channel OFF Microphone Audio HOLD TIME OFF ATTENUATION Ambient Level Time Figure 11. Off Attenuation, Hold Time, Adaptive Threshold, and Decay Time. Global Settings. Decay Time.
INTEGRATING THE UNIT INTO YOUR SYSTEM this value to 18 would result in the microphone signals being attenuated by 18 dB when gated off. This value is set independently for the automixers. Automixer Reference. When enabled, the echo canceller reference becomes a muted input in the automix so that far end audio coming from the speakers does not gate on local microphones. Reference Bias. Adjusts how much gain is applied to the Automixer Reference signal.
INTEGRATING Automixer and Bus Mixer Settings THE UNIT INTO YOUR SYSTEM To operate the Vortex device in any of the above possibilites, two global parameters need to be changed: the AUTOMIXER and the BUS MIXER (see Figure 12). The AUTOMIXER parameter chooses which automixer the input channel will be on (this is changed either on the AUTOMIXER page in Conference Composer or on the MATRIX MIXER page).
INTEGRATING THE UNIT INTO YOUR SYSTEM 1. Assign Inputs Assign each audio source to an input. Remember to include the conferencing equipment such as a video codec and any program audio. 2. Assign Outputs Try to assign as many outputs as you can to one Vortex device to make a simpler submatrix. The bussing gets more complicated if you choose to spread your outputs over several units. 3. Configure the submatrix.
THE EF BUS THE EF BUS The EF Bus is a high speed, low delay digital bus that includes the W, X, Y, and Z audio busses, the P bus, as well as the echo canceller bus reference and remote control information (for other EF devices). It can link up to 8 Vortex devices. The W, X, Y, Z Busses. The W, X, Y, and Z busses include NOM information and can be used for sharing microphone inputs, or for sharing mono or stereo program information.
THE EF BUS from the other devices. See Figure 13 below. The input mixes become inputs to the main matrix and can be mixed with the other inputs to create output mixes. Figure 13. W, X, Y, and Z submatrices, the P submatrix, and Exported Bus Reference. EF Bus Reference. In a system with multiple devices, if all devices need the same echo canceller reference, one device should be designated to put its echo canceller reference on the EF bus to be used as the EF Bus Reference.
THE EF BUS room and use the same reference, configure the echo canceller reference on one Vortex device and assign it to the EF Bus as the EF Bus Reference. Only one Vortex device out of multiple units linked together can put an echo canceller reference on the EF Bus. For each additional unit, assign the echo canceller reference to use the EF Bus Reference.
LCD MENU STRUCTURE LCD MENU STRUCTURE LCD Menu Tree The EF2211/EF2210 LCD menu structure is made up of nine menu trees: SYSTEM, PHONE CONTROL (EF2211 only), INPUTS, OUTPUTS, AUTOMIXER, MATRIX, PARAMETRIC EQ, PRESETS, and MACROS. Each menu tree is organized by levels and branches into multiple subcategories. The branches end with an adjustable parameter or value.
LCD MENU STRUCTURE parameter field and the parameter value. To change the parameter, the parameter must be flashing. To make the parameter flash (assuming the front panel is not locked) press ENTER. Once the parameter is flashing, use the UP and DOWN buttons to adjust the parameter value. The parameter is instantly updated while it is being adjusted — you should hear changes as the parameter is changing.
LCD MENU STRUCTURE SYSTEM MENU System Power On Preset Acknowledgement Mode Bus Reference Error Messages Front Panel Lock Front Panel Password Device ID Baud Rate Flow Control Meter Non-Volatile Memory Lock Non-Volatile Mem Password Screen Saver Last Restored Preset Software Version Reboot Vortex Figure 15.
LCD MENU STRUCTURE PHONE CONTROL (EF2211 ONLY) Auto Answer. Enables or disables auto answer. Auto Hangup Call Progress. Enables or disables auto hangup based on call progress messages. Phone Control Auto Answer Auto Hangup Call Progress Auto Hangup Loop Drop. Enables or disables auto hangup cased on loop drop. Country Select. Selects the country where you are using the unit. This must be set before you can use the unit and does not need to be set again unless you use the unit in a different country.
LCD MENU STRUCTURE INPUTS Inputs 1, T, A, B Acoustic Echo Cancellation (In 1) The input menu allows the user to adjust functions related to the input signals to the EF2211/EF2210. This menu contains ACOUSTIC ECHO CANCELLATION, AUTOMATIC GAIN CONTROL, AGC MAXIMUM, AGC MINIMUM, GAIN ADJUST, LEVEL MIC/LINE, MUTE, NOISE CANCELLATION, NOISE CANCELLATION LEVEL, PHANTOM POWER, REFERENCE ASSIGN, and AEC SUPPRESSION.
LCD MENU STRUCTURE LEC Suppression (Input T). Sets the amount of suppression used the line echo canceller (LEC). OUTPUTS The OUTPUT menu contains GAIN, NOM ACTIVE, and MUTE. As with the INPUT menus, this is done on a per channel basis. Outputs Output Gain Mute Output NOM Attenuation On/Off Output Delay Enable Output Delay Dynamics Processing (Out T) Figure 18. EF2211/ EF2210 Outputs submenu NOTE: Output T is the outgoing phone signal. This output is only available on the EF2211. Output Gain.
LCD MENU STRUCTURE AUTOMIXER MENU Automixer Global Settings These parameters configure how the Vortex automatic microphone mixer operates. Parameters include the following: DECAY TIME, HOLD TIME, CAMERA GATING THRESHOLD, BUS ID, CHAIRMAN MODE, CHAIRMAN MIC, LAST MIC ON MODE, LAST MIC NUMBER, LOCAL MAX NOM, GLOBAL MAX NOM, OFF ATTENUATION, AUTOMIXER, THRESHOLD TYPE, GATING MODE, ADAPTIVE THRESHOLD, MANUAL THRESHOLD, and GATE PRIORITY.
LCD MENU STRUCTURE Mixer Settings. Automixer Mixer Settings (AM1) Bus ID Chairman Mode Chairman Mic Last Mic On Mode Last Mic Number Local Max NOM Global Max NOM Off Attenuation Automixer Reference Reference Bias Bus Mixer. This command is used to assign one of the two internal automixers to one of the EF Bus automixer groups. Setting the Bus Mixer to the same number as the automixer on another Vortex device will allow the devices to be one large automixer.
LCD MENU STRUCTURE MATRIX MENU Matrix Main Matrix Gain Gate (In 1) The MATRIX contains commands for assigning input signals to output signals with appropriate gains applied or mutes applied. It also allows for Gating to be turned on for Input 1. This menu can apply gains to both the MAIN MATRIX and the SUBMATRIX. Crosspoint Gains. Assign input signals to output signals with appropriate gains applied. Gate. Applies gating from Input 1 to an Output. Mute. Applies mute to the crosspoint.
LCD MENU STRUCTURE PARAMETRIC EQ MENU Parametric EQ Input/Output EQ Channel Band Filter Type Frequency Bandwidth Gain Slope Filter Enable Figure 22. EF2211/ EF2210 Parametric EQ submenu The input equalizer is comprised of up to 5 bands of filtering. The whole group of filters for the channel can also be enabled/disabled without losing the settings for each band.
LCD MENU STRUCTURE PRESETS Restore. Restores the selected preset. Save. Saves the selected user preset (Presets 16-47). Factory presets (Preset 0-15) cannot be overwritten. Presets Restore Delete. Deletes the selected user preset (Presets 16-47). Factory Presets (Presets 0-15) cannot be deleted. Save Presets 16-47 Delete Presets 16-47 Figure 23. EF2211/ EF2210 Presets submenu MACROS Run Macro (0-255). Allows you to run macros from the front panel menu. Macros Run Macro (0-255) Figure 24.
TROUBLESHOOTING TROUBLESHOOTING AUTOMATIC MICROPHONE MIXER The microphone is not gating • • • • • • • Check if the microphone is assigned to an automixer. Check if the microphone is muted. Check microphone level. Is the microphone set to the appropriate mic or line level? Is phantom power on where needed? The Hold Time may be too low. Microphone channel gating On and Off too frequently during short pauses in speech might be the result of setting the Hold Time too low. Check Gating settings.
TROUBLESHOOTING tion of the EF2211/EF2210. If you hear residual echo, one of the following conditions may be causing the problem. Reverberation vs. Acoustic Echo Do not confuse the residual echo of remote speech with the reverberation of local speech. Reverberation of local speech is caused when the speech signal arrives at the microphone via several paths (the direct path and multiple reflections from surfaces in the room).
TROUBLESHOOTING loudspeakers. The loudspeaker audio is coupled into the room microphones acoustically, through direct and reflected acoustic paths, and perhaps also through mechanical coupling. The microphone signal is then amplified and sent to the AEC as the local microphone input signal.
TROUBLESHOOTING fied by 6 dB more than necessary. This adds 6 dB to the room gain, which may be sufficient to cause room gain problems. This situation could easily arise if, for example, the conferencing equipment is set up so that participants are too far from the microphone. In such a situation, after correct microphone setup the local microphone audio level may be too low because of the distance from the talker to the microphone. The microphone audio will most likely also be muddy and reverberant.
TROUBLESHOOTING Excessive Microphone Amplification For the EF2211/EF2210 to adapt effectively, saturation (overload or clipping) must not occur at the A/D converter supplying the microphone input. Saturation introduces nonlinear signal distortions into what the AEC expects is a linearly echoed version of the remote speech. Nonlinear distortion causes a degradation or divergence of the AEC’s internal model of the room acoustics.
TROUBLESHOOTING — D/A, amplifier, loudspeaker, microphone, and A/D — to cancel acoustic echoes. If you overdrive the loudspeaker or insert a dynamics processor before the echo canceller, the acoustic reflections picked up by the microphone do not match the signal fed to the loudspeaker. They are distorted copies of this signal. The EF2211/EF2210 cannot effectively cancel this distorted signal.
TECHNICAL SPECIFICATIONS TECHNICAL SPECIFICATIONS MECHANICAL SPECIFICATIONS Dimensions 19” (483 mm) W x 9.6” (244 mm) L x 1.75” (45 mm) H (full rack unit) Weight 4 lb. (1.8 kg) dry 5.5 lb. (2.5 kg) shipping Connectors Audio: Mini (3.5mm) quick connect terminal blocks RS-232: DB9F EF Bus In/Out: RJ45 Phone In/Out: RJ11 * Control/Status: DB25F * Only applies to the EF2211.
TECHNICAL SPECIFICATIONS COMPLIANCE The Vortex EF2211/EF2210 complies with the ITU G.167 Recommendation for AEC, FCC part 15, and CE requirements. USA and Canada This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: 1. 2. NOTE This device may not cause harmful interference, and This device must accept any interference received, including interference that may cause undesired operation.
TECHNICAL SPECIFICATIONS • • If, in the unlikely event that this equipment causes harm to the network, the telephone company will notify you in advance that temporary discontinuance of service may be required. But if advance notice isn't practical, the telephone company will notify you as soon as possible. Also, you will be advised of your right to file a complaint with the FCC if you believe it necessary.
TECHNICAL SPECIFICATIONS NOTICE: The Ringer Equivalence Number (REN) assigned to each relevant terminal device provides an indication of the maximum number of terminals allowed to be connected to a telephone interface. The termination on an interface may consist of any combination of devices subject only to the requirement that the sum of the Ringer Equivalence Numbers of all the devices does not exceed 5.
TECHNICAL SPECIFICATIONS Con la presente Polycom Ltd. dichiara che il EF2211 soddisfa i requisiti essenziali e le altre disposizioni pertinenti della direttiva 1999/5/CE. Verklaring van overeenstemming: Hierbij verklaart Polycom Ltd. dat diens EF2211 voldoet aan de basisvereisten en andere relevante voorwaarden van EG-richtlijn 1999/5/EG. Declaração de Conformidade: Através da presente, a Polycom Ltd.
TECHNICAL SPECIFICATIONS L’Installation doit être exécutée conformément à tous les règlements nationaux applicable au filage électrique. Plug acts as Disconnect Device* The socket outlet to which this apparatus is connected must be installed near the equipment and must always be readily accessible VORTEX EF2211/EF2210 Reference Manual 48 Technical Support: 800.932.
CONFERENCE SYSTEM DESIGN CONFERENCE SYSTEM DESIGN Good audio or video conferencing is more than acoustic echo cancellation. Before installing the EF2211/EF2210, you should consider how your whole conference system will work together.
VORTEX EF2211/EF2210 Reference Manual 50 A/D Mic/Line EN 1 + - A + - Level adjust A/D PEQ Matrixing PEQ + - PEQ Line D/A + - A D/A Level adjust Line Phantom AMP 1 R1, R2, Bus Echo Canceller On Off Noise Canceller On Off AGC B A/D PEQ PEQ D/A + - Parameters PEQ B + - Level adjust Line EN (Echo Canceller, Noise Canceller) + - Amplifier Output On Off Mute TLP PEQ Parameters Gate Tone Gen.
EF2211/EF2210 BLOCK DIAGRAM EF2210 Amplifier Output 1 A Line Line + - + - B Line + - + - AMP RS-232 D/A D/A D/A EF Bus PEQ PEQ PEQ Matrixing EN PEQ PEQ A/D A/D A/D Level adjust Level adjust Level adjust Phantom Mic/Line + - + - + - 1 A B EN (Echo Canceller, Noise Canceller) Ungated Echo Canceller R1, R2, Bus Noise Canceller On Off AGC On Off PEQ Parameters Mute On Off Gate Gated Parameters Figure 29. Inside the EF2210 © Polycom, Inc.
CONNECTOR PINOUTS CONNECTOR PINOUTS EF Bus EF BUS IN 8 1 1 8 The EF Bus uses RJ45 connectors. These should be used with category five twisted-pair cable. The total distance of the EF Bus should be less than 4.5 m. The EF Bus must be connected so that the EF Bus In of one box is connected to the EF Bus Out of another. Connecting the EF Bus In to another EF Bus In (or Out to Out) will not work.
CONNECTOR PINOUTS Input/Output Remote Control Port INPUT 13 Logic Input: Pins 1-24 are inputs 1-24, respectively. Pin 25 is ground. 1 25 14 REMOTE CONTROL Logic Output: Pins 1-20 are outputs 1-20, respectively. Pins 21-25 are ground. Each ground pin should be used with only 4 outputs. For example, outputs 1-4 could be connected to LEDs, which are connected to ground pin 1. OUTPUT LEDs can be used without series resistors (we have provided series resistors in the circuitry).
CONNECTOR PINOUTS CONNECTING UNBALANCED RCA TO BALANCED TERMINAL BLOCK 3.5 mm Terminal Block Connector RCA Male Tip Red Black Red + 1 Black - 2 Shield 3 Ring Figure 30. Cable construction for connecting unbalanced RCA to balanced 3-conductor terminal block. 1. 2. 3. Connect RCA Tip to terminal block pin 1. Connect RCA Ring to terminal block pin 2. Connect terminal block pin 3 to Shield, and leave Shield floating on RCA end. Caution! Do NOT connect the shield at both ends.
CONNECTOR PINOUTS ADDITIONAL NOTES Caution! Caution! Caution! Caution! Caution! © Polycom, Inc. Failure to use all four screws to attach the EF2211/ EF2210 to the rack may result in uneven loading and cause a safety hazard. Ensure that the power supply is securely located such that it cannot become dislodged and fall. Such a fall could cause personal injury or equipment failure.
WARRANTY INFORMATION WARRANTY INFORMATION What is covered Any defect in materials or workmanship. For how long Two years. What we will do If your Vortex EF2211/EF2210 product is defective and returned within two years of the date of purchase, we will repair or, at our option, replace it at no charge to you. If we repair your Vortex product, we may use new or reconditioned replacement parts.
WARRANTY INFORMATION use violates Part 779 of the Export Administration Regulations of the United States Department of Commerce. If your Vortex product is not covered by our warranty, call us at (800) 932-2774 for advice about whether we will repair your Vortex product and for other repair information, including charges. Polycom, at its sole discretion, may replace rather than repair your Vortex product with a new or reconditioned one of the same or similar design.
DEFINITION OF TERMS DEFINITION OF TERMS Acoustic Echo Acoustic echo occurs in a conferencing or distance learning system when the remote speech played in the loudspeakers is picked up by microphones in the room and is transmitted back to the remote end. This transmitted signal is a delayed version of the original, which causes the echo. Acoustic Gain Acoustic gain is a term used in conjunction with sound reinforcement.
DEFINITION OF TERMS EF Bus The EF Bus is a digital bus that includes the W, X, Y, and Z audio busses as well as the echo canceller reference and remote control information. It can be used to link multiple Vortex devices. Equalization Equalization is the process of adjusting frequency characteristics of an audio signal. Line Echo Line echo is caused by reflections of the audio signal from the telephone hybrid. The EF2211/EF2210 is an example of a device that includes a line echo canceller.
DEFINITION OF TERMS room gain of this microphone channel is said to be 0 dB. If the reflected signal picked up by the microphone is higher than the level of the signal sent to the line output to your amplifier, that microphone channel has positive room gain. The more positive the room gain, the harder the AEC must work to determine which signal is an echo and which is a local speech signal. VORTEX EF2211/EF2210 Reference Manual 60 Technical Support: 800.932.
INDEX INDEX A B C D E Acoustic Echo Cancellation, AEC ........................................................10, 16, 17, 30, 38, 39, .................................................................................................................43, 49, 58 Automatic Gain Control (AGC) ............................................................30, 58 Automixer, Adaptive Threshold ..........................................................20, 33 Automixer, Adaptvie Threshold ............................
INDEX F G I L M N O P Factory Default Settings, Preset 0 .....................................................9, 11, 14, 21 Front Panel Lock ...................................................................................28 Ground ....................................................................................................53 Ground, Chassis ....................................................................................54 Ground, Logic Input ..............................................
INDEX Power On Preset ...................................................................................11, 25 Presets ....................................................................................................59 R S T V Reference, AEC .....................................................................................16–17, 23, 30, 58, 59 Reverberation ........................................................................................49 Room Gain .........................................
Polycom, Inc. Installed Voice Business Group 9040 Roswell Road Atlanta, GA 30350 Phone: (800) 932-2774 www.polycom.com Technical Support: (800) 932-2774 vortex@polycom.com Polycom®, Vortex®, and the Polycom logo are registered trademarks of Polycom, Inc. in the United States and various countries. Copyright © 2003 Polycom, Inc. All rights reserved.
