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®
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AFS 224
Dual Channel Advanced Feedback Suppression Processor
User Manual
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IMPORTANT SAFETY INSTRUCTIONS WARNING FOR YOUR PROTECTION CAUTION READ THESE INSTRUCTIONS: RISK OF ELECTRIC SHOCK DO NOT OPEN KEEP THESE INSTRUCTIONS ATTENTION: RISQUE DE CHOC ELECTRIQUE - NE PAS OUVRIR WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC HEED ALL WARNINGS SHOCK DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE FOLLOW ALL INSTRUCTIONS The symbols shown above are internationally accepted symbols that warn of potential hazards with electrical DO NOT USE THIS APPARATUS NEAR WATER product
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IMPORTANT SAFETY INSTRUCTIONS U.K. MAINS PLUG WARNING A molded mains plug that has been cut off from the cord is unsafe. Discard the mains plug at a suitable disposal facility. NEVER UNDER ELECTROMAGNETIC ANY CIRCUMSTANCES SHOULD YOU INSERT A DAMAGED OR CUT MAINS PLUG INTO A 13 AMP POWER SOCKET. Do not use the COMPATIBILITY mains plug without the fuse cover in place. Replacement fuse covers can be obtained from your local retailer. Replacement fuses are 13 This unit conforms to the Product a
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Table of Contents AFS 224 Table of Contents Defining the AFS 224..............................................i Service Contact Info...............................................ii Warranty..................................................................ii Installation Recommendations...............................1 Basic Connections ..................................................1 Rear Panel Connections.........................................2 Front Panel Connections......................
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AFS 224 AFS 224 Operation ®
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Introduction AFS 224 Congratulations on your purchase of the dbx Professional Products AFS 224. The AFS 224 Advanced Feedback Suppression processor was designed to provide state-of-the-art feedback INTRODUCTION elimination processing, while maintaining a simple and intuitive control interface. From the powerful DSP module to the no-nonsense user interface, the AFS 224 provides all the process- ing and control necessary for both installation and live use. The AFS 224 is an absolute must for any
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Introduction AFS 224 dbx AFS™ Competitor’s Feedback Elimination 1/3 Octave EQ For more information regarding dbx Advanced Feedback Suppression (AFS™) technology, please refer to the white paper section online at: www.dbxpro.com. Service Contact Info If you require technical support, contact dbx Customer Service. Be prepared to accurately describe the problem. Know the serial number of your unit - this is printed on a sticker attached to the rear or side of the unit. If you have not already taken
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Installation / Connections Operation AFS 224 a period of two years. A Return Authorization number must be obtained from dbx by telephone. The company shall not be liable for any consequential damage as a result of the product's use in any circuit or assembly. 4. dbx reserves the right to make changes in design or make additions to or improvements upon this product without incurring any obligation to install the same additions or improvements on products previously manufactured. 5. The foregoing
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Rear and Front Panels Operation AFS 224 Rear Panel AFS 224 Rear Power Cord Receptacle: Connects AC power to the AFS 224. Input Connectors: Two types of input connectors are provided for input connections: female locking XLR type connectors, and 1/4” tip-ring-sleeve phone jack connectors. The maximum input level that the processor can accept is +20dBu (ref: 0.775Vrms). Operating Level Switch: This button allows you to select between either +4dBu or -10dBV nominal operating level. Output Connec
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User Setup Operation AFS 224 AFS 224 Filter Q's +3 +3 +2 +2 Music High - 1/80th Octave +1 +1 -0 -0 -1 -1 Music Med - 1/20th Octave -2 -2 d d B -3 -3 B u Music Low - 1/10th Octave u -4 -4 -5 -5 Speech - 1/5th Octave -6 -6 -7 -7 -8 -8 -9 -9 700 750 820 850 900 .95k 1k 1.2k Hz Live Filter Lift: Live Filter Lift provides maximum sonic integrity by removing unnecessary feedback filters. This button is used to select the live filter lift times and are indicated as follows: LED Lift Time Not Lit
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User Setup Operation AFS 224 If no insert points are available, then method 4 would be utilized. In this situation, be sure that the AFS 224 input level allows the 0 and +10 dBu LEDS to light as indicated above. The input level to the amplifiers may have to be reduced in this situation so that they are not over- driven by the signal from the AFS 224. B – Setup Mode The AFS 224 setup mode is used to set the Total Number of Filters and the Number of Fixed Filters in each channel. The number of
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User Setup Operation AFS 224 C-1 Ringing out a system Fixed mode filters are set before a performance in a process called "ringing out a system". This is done after all other system EQ'ing has been done. First, bring down the main mix, turn off all music sources and open all the mics. Place the AFS 224 into fixed mode by pressing the button for the channel. A button lighting green indicates Fixed mode for that channel. Select the channel’s filter type by pressing the channel’s
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Operation User Setup AFS 224 D-1 Using Live Filter Lift Live Filter Lift provides maximum sonic integrity by removing unnecessary feedback filters. The Live Filter Lift function provides a timer for each of the Live Filters. This timer length can be adjusted by pressing the button, and can be switched between off, 1 minute, 10 minutes or 60 minutes. The filter lift default time is 10 minutes from the facto- ry. If Live Filter Lift is on, once a filter’s time period has expir
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Operation Application Guide AFS 224 Applications Application 1 - Insert On the Microphone Channel This application is ideal for dedicated feedback suppression on microphone channels of a mix- ing console. This application provides the user with individual channels of 24 filter of feed- back suppression per microphone. 1. Connect the channel insert output from the mixer to the input of the AFS 224. 2. Connect the output of the AFS 224 to the insert return of the mixer. For maximum performance a
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Application Guide Operation AFS 224 Application 2 - Insert On the Main Stereo Outputs of a Mixing Console This application is ideal for dedicated feedback suppression on the outputs of a mixing con- sole. This application provides the user with dual channels of 24 filters of feedback suppres- sion per channel. 1. Connect the stereo output inserts of the mixer to the inputs of the AFS 224. 2. Connect the outputs of the AFS 224 to the insert returns of the console. 3. Apply power to the mixer a
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Applications Guide Operation AFS 224 Application 3 - Insert on the Subgroups of a Mixer This setup is ideal for applications that require feedback suppression on certain instruments such as microphones, while keeping instrument that desire feedback (such as guitars) separat- ed. This application provides the user with dual channels of 24 filter suppression per stereo channel of the mixing console subgroup. 1. Connect the stereo output inserts of the mixer to the inputs of the AFS 224. 2. Conne
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Applications Guide Operation AFS 224 Application 4- Connected Inline with the Outputs of a Mixer This application is ideal for dedicated feedback suppression on the outputs of a mixing con- sole. This application provides the user with dual channels of 24 filters of feedback suppres- sion per output channel of the mixing console. 1. Connect the outputs from the mixer to the inputs of the AFS 224. 2. Connect the outputs of the AFS 224 to the power amps. 3. Apply power to the mixer and amplifier
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Block Diagram Operation AFS 224 Block diagram ® 386 User Manual AFS 224 User Manual 11 AFS 224 Input meter Block Diagram Input RF A/D D/A Inputs RF Filter TYPE IV™ DSP Outputs Filter Micro Processor CLIP Detect Filter meter LEDs Bypass Bypass Programmable Type Logic Type Live Filter Lift Live Filter Lift Mode Mode
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Specifications Operation AFS 224 Specifications Analog Inputs: Number of Inputs: 2 Connectors: Female XLR and 1/4” TRS Type: Electronically balanced/unbalanced, RF filtered Impedance: Balanced 50kΩ , Unbalanced 25kΩ Max input line level: +20dBu CMRR: >40dB, typically >55dB @ 1kHz Analog Outputs: Number of Outputs: 2 Connectors: Male XLR and 1/4” TRS Type: Electronically balanced/unbalanced, RF filtered Impedance: Balanced >120Ω , unbalanced >60Ω Max Output Level: +20dBu A/D Performance: Type
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® A Harman International Company 8760 South Sandy Pkwy. Sandy, Utah 84070 Phone: (801) 568-7660 Fax: (801) 568-7662 Questions or comments E•mail us at: customer@dbxpro.com or visit our World Wide Web home page at: www.dbxpro.com 18-6398-A
