Converge Pro White Paper
©2009 ClearOne Communications, Inc. All rights reserved. No part of this document may be reproduced in any form or by any means without written permission from ClearOne Communications, Inc. Printed in the United States of America. ClearOne Communications reserves specific privileges. Information in this document is subject to change without notice. Converge Pro Professional Conferencing Systems White Paper ClearOne Part Number 803-151-880 Rev 1.8. August 2009.
Table of Contents CHAPTER 1: Introduction. ����������������������������������������������1 Overview. ������������������������������������������������������������������������������������������������������ 1 Converge Pro 880 Product Description. ������������������������������������������������������� 3 Converge Pro 880T Product Description. ����������������������������������������������������4 Converge Pro 840T Product Description.
CHAPTER 1: Introduction Overview The Converge Pro™ product line provides a complete sound system for collaboration, presentation, distance communications and any other multimedia audio event. The Converge Pro audio system is extremely flexible allowing it to be used in a wide range of applications, with superior audio quality.
Telephone Hybrid Enhancements (880TA, 880T, 840T, and TH20) Custom telephone line settings for international teleconferencing and in-country localization • Type I & Type II auto-sensing telephone interface (U.S./E.U.
converge pro mixer line - channel table Product Mic/Line Inputs Line Inputs Power Amp Processing Channels Fader Channels Output Telco E-Bus Converge Pro 880TA (New) 8 4 4 (35W) 8 0 8 1 Yes Converge Pro 880T 8 4 1 (5W) 8 4 12 1 Yes Converge Pro 880 8 4 8 4 12 0 Yes Converge Pro 8i 8 4 8 4 0 0 Yes Converge Pro 840T 4 4 4 4 8 1 Yes Converge Pro TH20 0 2 0 0 2 1 Yes 1 (5W) *Power Amp wattage is based on 8ohm load. 3 www.clearone.
Converge Console Description The Converge Console software provides a powerful, intuitive interface for configuring and controlling your Converge Pro system. While you can use LCD Programming for some simple configuration tasks, you must use Console for the advanced configuration tasks required to customize Converge Pro units for your application.
object pane and drop it onto the control/status portion of the Control Tab screen. Macro Objects Macro objects allow you to save macros into the database and reuse them. After saving a macro as an object, it appears in the object pane of Console. To use a macro object, drag it from the Objects Pane and drop it onto the Macro Command List portion of the Macro Tab screen. Preset Objects Preset objects allow you to save preset configurations into the Database and reuse them.
Controls and Connections The following diagrams describe front panel controls and back panel connectors. Front Panels Converge Pro 880 Front Panel A B C D E F G ClearOne Converge 880 11: CONVERGE880-77 IPA: 192.168.1.1 1.0.00 CONVERGE PRO 880 1 2 3 4 5 6 MENU SELECT ESC METER -30 -10 -4 0 +4 +8 +12 7 8 Converge Pro 880T Front Panel Converge Pro 880TA Front Panel A B C D E F G I H ClearOne Converge 880TA DO: CONVERGE880-91 IPA: 0.0.0.0 1.1.
Converge Pro 8i Front Panel A B C D E F G ClearOne Converge 8i A6: CONVERGE8i-1C IPA: 192.168.1.4 1.0.00 CONVERGE PRO 8i 1 2 3 4 5 6 MENU SELECT ESC METER -30 -10 -4 0 +4 +8 +12 7 8 Converge Pro TH20 Front Panel A C D E F G ClearOne Converge TH20 CONVERGE PRO TH20 TELCO TX RX 2F: CONVERGETH20-3A IPA: 192.168.1.3 1.0.00 MENU ESC SELECT TELCO ON / OFF METER -30 -10 -4 0 +4 +8 +12 H I Front Panel Control Descriptions A.
Rear Panels 1 2 Rear Panel 3 Converge Pro 880 VOLTAGE RANGE 100-240 VAC 2A FREQUENCY 50Hz / 60Hz 1 MIC / LINE 2 3 4 1 LINE OUT 2 3 4 5 6 7 8 RS-232 CONTROL / STATUS 9 LINK IN 4 PC + - 9 10 LINE IN 11 12 LINE OUT 10 11 9 12 A B LAN 5 6 7 8 5 6 7 8 LINK OUT Converge Pro 880T Rear Panel Converge Pro 840T 1 2 Rear Panel 3 4 5 6 7 8 9 LINK IN VOLTAGE RANGE 100-240 VAC 2A FREQUENCY 50Hz / 60Hz + 1 MIC / LINE 2 3 4 1 LINE OUT 2 3 5 4 PC - LINE IN 6 7 8 L
Converge 880TA Rear Panel 1 2 3 4 1 2 3 4 1 2 3 4 5 6 7 8 5 6 7 8 R , 7 9 8 11 LINE OUT 5 Rear Panel Connectors 6 6 LINE IN 7 8 10 12 1. AC Power: IEC connector, 100 – 240VAC auto-adjusting, 50/60Hz. 2. Mic/Line Inputs: Mini-terminal push-on connector for connecting any combination of microphone and/or line level inputs. (880: 8 inputs. 880T: 8inputs; 840T: 4 inputs. 8i: 8 inputs. TH20: 0 inputs. SR 1212: 8 inputs.) 3.
12. Speaker Conection: For external speaker (4Ω – 16Ω). An internal four channel, 35 watt per channel amplifier. 13. Speaker Connection: For external speakers (70v or 100v system). An internal four channel, 35 watt per channel amplifier. NOTE: The Telco Set port is not available for use when the line is off-hook. 10 www.clearone.
CHAPTER 2: Echo and Noise Cancellation Echo Cancellation Acoustic echo is a significant challenge to overcome in most any teleconferencing applications. Acoustic echo can compromise a teleconference because it impairs participants’ abilities to understand others and communicate with one another. Acoustic echo occurs when microphones pick up loudspeaker audio and return it to the originating teleconference site. This echo can cause a conference participant to stop speaking while listening to the echo.
The Converge Pro 880’s Distributed Echo Cancellation places an echo canceller on each mic input for dramatically improved echo cancellation (Figure 2.2). In this example, audio from a distant room is sampled. This audio is a reference for each echo canceller on every mic. When sampled audio (acoustic echo) is detected by the echo canceller, the echo is eliminated.
CHAPTER 3: Processing Blocks The Converge Pro 880 and 8i features the power of eight processing blocks, which are dedicated signal processing resources that can be applied to any mic or line input routed to it. The Converge 840T features four processing blocks. Within each processing block, compression, delay, gain adjustments, and up to 15 different filters may be applied to any mic/line input, or combination of inputs routed to the block.
• Notch Filter. A band-stop filter that can remove a select range of frequencies. Commonly used for removing specific resonant frequencies from a system. • Parametric Equalizer. A multi-band variable equalizer that allows the user to define the amplitude of the filter, shift the center frequency of the filter, and control how wide the range is to which the equalizer is applied. Filters are configured and adjusted using Converge Console software.
In the past, properly identifying the frequencies of the feedback modes and correctly placing the narrow-band filters was a time consuming endeavor. Today automatic feedback eliminators greatly reducing the time it takes to equalize a system. ClearOne has recently developed DARE (Dynamic Automatic Resonance Eliminator), the most advanced feedback elimination algorithm available.
CHAPTER 4: Inputs and Outputs Mic\Line inputs Balanced audio is input at the rear panel Phoenix connector. Mic or line level is selected and phantom power is provided (if required). Converge Pro devices convert input audio from analog to digital for processing by the DSP engine. Once converted to digital, audio level is controlled. This function, along with all other functions, can be adjusted via local or remote external control interfaces, or PCs connected via USB, network, or RS- 232 port.
The next stage is the channel mute. After the channel mute stage, non-gated audio is applied to the routing matrix for outputs that need direct audio. The final stage (automixing) determines how the audio is directed into the postgating input to the routing matrix. Each input can be set for a variety of automixing functions, including activation settings, chairman override, and adaptive ambient mode. These functions determine when, how, and why an individual microphone gates on or off.
CHAPTER 5: Automatic Mic Mixing Intelligible, Reliable Audio Systems that produce intelligible and reliable audio are key to facilitating effective communication. A quality conferencing system meets the following objectives: • The audio must be transparent. Users should not have to think about the audio. • The audio must not fatigue the users. Distorted, noisy audio will cause users to break off discussions before a natural conclusion occurs.
Converge/Converge Pro devices are designed to implement automatic microphone mixing, which increases audio intelligibility by reducing reverberation and noise. Converge Pro implements its mixing function completely in the digital domain, which greatly increases auto mixing precision. All audio is routed through the Converge Pro (both microphone and speaker audio), which means the Converge Pro can more accurately make microphone activation decisions.
speak at the same time. • First Mic Priority Mode (On or Off). This feature increases the audio level required to gate on additional microphones after the first mic gates on. This helps ensure that only one mic gates on when a person speaks. • Last Mic On/Mic1-8/Off. Last Mic On leaves the last activated mic on until a new one is activated. Mic 1–8 mode reverts back to the mic you’ve selected for Mic 1–8 on when all other mics gate off.
Mixing Parameters Parameter Range Description Microphone Activation Auto gate, manual gate, on/off Sets the method of microphone gating. Chairman Override Adaptive Ambient mode PA Adaptive mode Maximum number of mics on First Mic Priority mode Last Mic mode Gate Ratio Adjust Off Attenuation Adjust Hold Time Decay Rate Manual Ambient Level NOM/Constant Gain mode Figure 5.5 21 www.clearone.com On/off When a chairman override channel is gated on, all non-chairman inputs are gated off.
CHAPTER 6: Audio Routing Matrix Mixing One of the most important functions of the Converge Pro audio conferencing solution is matrix routing of audio signals. Like all Converge Pro device functions, all routing is executed in the digital domain. The Converge Pro audio matrix mixes, distributes and routes audio from any input to any output with level control at each cross point. The routing chart below (Figure 6.1) shows the default Converge Pro routing. Figure 6.1 Inputs • Mic/line inputs.
Expansion Bus The expansion bus is a digital mix-minus bus that is used to connect Converge Pro units. Audio placed on the bus for a particular unit is not fed back to that unit, but is available to all other units in the system. Audio on any linked Converge Pro unit can be placed on a bus channel, or taken off the bus and routed to any output of that unit. The Converge Pro system has 12 digital mix-minus buses with the following default programming. • I–R Buses.
From Matrix Delay 15 Filters All Pass Low Pass High Pass Low Shelving High Shelving Notch PEQ CD Hom Bessel Cross Butterworth Linkwitz-Riley 500ms Mute Compressor To Matrix Attenuation Figure 6.3 Faders There are four assignable fader channels in the Converge Pro 880/880T/8i/840T. Faders are a way to “pre-mix” a number of input channels, process the “pre-mix”, and send it to an output. They are different from processing blocks in that they do not include filters, compression, limiting or delay.
CHAPTER 7: System Control Converge/Converge Pro units provide a variety of options for system control. You can create up to 32 presets and up to 255 macros to change room configurations or run a series of commands.
Room combining Volume UP LED Status All separate Status All combined Status 1 + 2: 2 + 4 Status 1 + 2: 2 + 4 +5VDC LED Volume UP Control status Control status +5VDC LED Volume UP +5VDC LED Volume UP +5VDC +5VDC Figure 7.1 ClearOne Control Devices Operation of linked Converge Pro units can be done via the USB, RS-232 serial or Ethernet connections. Converge Console is used with the USB or Ethernet port. Audiovisual controllers can operate a Converge Pro system via Ethernet or RS-232.
• PA Adapt/AEC Reference buses: These buses provide a system-wide bus for input channels to receive a reference input for PA Adaptive Mode. Connecting To The Expansion Bus Each Converge Pro comes standard with one expansion bus cable. The maximum cable distance allowed between any two Converge Pro units on an expansion bus network is 200 feet (60 meters). ClearOne recommends using category five twisted pair (10BaseT) cable. 27 www.clearone.
CHAPTER 8: Applications The sophistication and adaptability of Converge Pro devices allows them to control and enhance many audio applications. Following are four applications where Converge Pro forms the centerpiece of a high-quality audio system. Distance Learning In a typical distance learning application, the primary source of audio comes from the instructor’s wireless microphone.
hearing these conversations, noise masking can be sent out of the jurors’ speakers. Everything that transpires in the courtroom must be recorded. You can configure Converge Pro devices to accommodate this requirement by routing all outputs to the court recorder–without gating. Figure 8.2 Boardroom A boardroom application is a good example of a situation where microphone mixing and gating become critical to providing seamless dialogue between several people seated around a large table and at distant sites.
Glossary Acoustic Echo Cancellation (AEC) A process in which acoustical echo is removed from a signal. AEC can be used to remove unwanted signals from mic audio if the unwanted acoustic signal is available separately as an electronic signal. Adaptive Ambient This portion of the mixer monitors the varying ambient noise level in the room and changes the threshold level at which a microphone gates on.
Constant Directivity Horn Equalizer (CD Horn EQ) Horn drivers commonly used in arrays in arenas and auditoriums have an inherent 6dB/octave high frequency rolloff. The Converge Pro 880/840T CD Horn EQ compensates for this characteristic. Converge Console Software The Converge Pro setup and configuration software. Crossover A device that passes designated frequency segments of an audio signal to various loudspeaker elements in a sound system.
First Mic Priority Increases the audio level required to gate on additional microphones after the first mic is on. This helps ensure that only one mic gates on when a person speaks. Gain The amount a signal is increased over a given reference, typically 0. Normally specified in dB (decibels). On the Converge Pro 880/840T, gain is adjustable from -65 to 20dB (85dB range) in .5dB increments. Gain Structure The configuration of parameters which define gain adjustment of a signal.
Number of Open Mics (NOM)/Constant Gain Mode Adjusts the output level based on the number of mics gated on and routed to an output. Off Attenuation The amount of level reduction a microphone is given when the microphone is not gated on. PA Adaptive Mode The Converge Pro 880/840T recognizes how much loudspeaker audio is picked up by the microphones and then uses this level as the new ambient level when audio is present at the power amplifier.
Signal Generator A device for generating a reference tone for sound system calibration purposes. Speech Leveler Essentially an AGC applied to a speech signal after processing by a noise cancellation stage. Acts only on voice signals. Does not pull up the noise floor during periods of no signal. Table View Displays the numerical values of the filter parameters for all nodes of the active filter display.
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Converge Pro 880T Overview The 880T leverages the rich functionality of the Converge Pro 880, and adds a built-in telephone interface and power amplifier for standalone conferencing applications. The 880T also provides industry-leading expansion capabilities, allowing you to connect it with other Converge/Converge Pro units for complex installations.
Converge Pro 840T Overview The successor to the industry-leading XAP® 400. Leveraging the rich functionality of the flagship ConvergeTM Pro 880, the new 840T includes a built-in telephone interface and power amplifier for standalone conferencing applications. It also provides expansion capability with other ConvergeTM Pro mixers for complex installations.
Converge Pro 8i Overview An input-only expansion box for the Converge Pro platform. The 8i delivers new economical configuration flexibility. It can be added to 880 or 840T systems for additional mic and line inputs, allowing customers to match the number of inputs and outputs required for audio conferencing and sound reinforcement installations.
Converge Pro TH20 Overview The successor to the industry-leading XAP® TH2. The TH20 enables conference call functionality for ConvergeTM Pro installations with its single telephone line connection. Up to 16 units can be linked for greatly expanded conferencing capability. It also adds two line-level inputs and outputs for increased system capacity.
