308 VCA Volume Control/ Loudness EQ
Contents
1. 308 VCA Volume Control Loudness EQ 308 VCA VOLUME CONTROL LOUDNESS EQ 308 VCA Volume Control Loudness EQ User s Guide July 2000 Symetrix Inc All rights reserved Printed in the United States of America Symetrix Part Number 53308 0A00 The information in this guide is subject to change without notice Symetrix Inc shall not be liable for technical or editorial errors or omissions contained herein nor is it liable for incidental or consequential damages resulting from the furnishing performance or use of this material Mention of third party products is for in formational purposes only and constitutes neither an endorsement nor a recommen dation Symetrix assumes no responsibil ity with regard to the performance or use of these products Under copyright laws no part of this user guide may be reproduced or transmitted in any form or by any means electronic or mechanical without permission in writing from Symetrix Inc If however your only means of access is electronic permission to print one copy is hereby granted Permission to copy the Architects and Engineers Specificiations for written proposals specifying equipment for sound reinforcement systems is also granted Symetrix Inc 14926 35th Ave West Lynnwood WA 98037 2303 USA Tel 425 787 3222 Fax 425 787 3211 Web www symetrixaudio com Email symetrix symetrixaudio com Symetrix 308 VCA Volume Control Loudness EQ2. Control Voltage Ramp Generator GND 4 b gt Ramp Generator GND Potentiometer JUU JUU a _CW SO a a cal ee eee CCW W W CCW o cw e eee eee eee eee eee eee eel Symetrix CONTROL EQ DEPTH AUDIO OUT AUDIO IN VOLUME CONTROL POTS 10K OHMS LINEAR TAPER RAMP1 GND1 GND2 RAMP2 24V 1 1 P 2 z 1 7 2 POWER CONNECT TO CTL1 10V Ba GND th th ch th INPUT amp SYMETRIX 2 PS 3 OR PS 3E 2 a Q POWER SUPPLY ONLY CHANNELS 1 and 2 Control Voltage Ramp Generator GND L Jumper connects RAMP1 and CTL2 Potentiometer POTENTIOMETER PIN CONNECTION TO THE 308 PINS Potentiometer Pins 308 Channel 1 Pins 308 Channel 2 Pins CW high 10V 10V W Wiper CTL1 CTL2 CCW low GND1 GND2 Symetrix 308 VCA Volume Control Loudness EQ User s Guide Making Hardware Connections Overview of Rear Panel Connectors and Controls Fast First Time Setup Controlling Channel Levels From a Potentiometer or Voltage Ramp Controlling Channel Levels By a Variable Resistor Unbalanced Connections Input and Output Connector Wiring Controlling Channel Levels By a Variable Resistor ie a rheostat Setup for Remote Output Mute This setup provides compatibility with certain remote volume control panels A resistance of 10K ohms results in unity gain A resistance of 0 ohms short circuit results in maximum attenuation Yo
3. Ramp Generator GND lt 0 to 10V Symetrix RC 3 Remote Control SYMETRIX RC 3 REMOTE CONTROL PIN CONNECTION TO THE 308 PINS RC 3 Pins 308 Channel 1 Pins 308 Channel 2 Pins 10V 10V 10V CTL CTL1 CTL2 GND GND1 GND2 RAMP CONTROL VOLTAGE PIN CONNECTION TO THE 308 PINS Device Pins 308 Channel 1 Pins 308 Channel 2 Pins Ramp generator GND GND1 GND2 Control voltage CTL1 CTL2 Symetrix 308 VCA Volume Control Loudness EQ User s Guide Making Hardware Connections Overview of Rear Panel Connectors and Controls Fast First Time Setup Controlling Channel Levels From a Potentiometer or Voltage Ramp Controlling Channel Levels By a Variable Resistor Unbalanced Connections Input and Output Connector Wiring Controlling Channel Levels From a Potentiometer or Voltage Ramp Setup for Remote Control To use two potentiometers to control each channel Connect the potentiometers to the CONTROL Euroblock connectors Its 2 y etrix vane come on een EU DEPTH e ar om A 2 2 24 pots must be 10k ohms linear taper PA ee CTLi 10V jen GND 1 2l H4 taH tlp ta and the cable should be 2 conductor INPUT SYMETRIX o i tt tt S 09 n 0 POWER D a with shield You can locate the CE saon ETAT Ally El Gel EL Fl potentiometers up to 500 feet from po the 308 unit Stereo signals can be adjusted by using one potentiometer CHANNEL 1 CHANNEL 2 Control Voltage lt
4. User s Guide Contents Before You Begin What Ships in the Box Getting Help Optional Rackmount Accessories Notational Conventions in this User Guide Operational Safety Summary Equipment Markings 308 Product Information Product Summary Features Making Hardware Connections Overview of Rear Panel Connectors and Connections Fast First Time Setup Controlling Channel Levels From a Potentiometer or Voltage Ramp Controlling Channel Levels by a Variable Resistor Unbalanced Connections Input and Output Connector Wiring Ww w N N N NN 10 11 Signal Flow Diagram Troubleshooting Hardware Specifications Architects and Engineers Specifications Warranty Service Declaration of Conformity 12 13 14 15 16 17 18 Symetrix 308 VCA Volume Control Loudness EQ User s Guide Before You Begin What Ships in the Box Getting Help Optional Rackmount Accessories Notational Conventions in this User Guide Operator Safety Summary Equipment Markings What Ships in the Box Getting Help M The 308 unit If you have technical questions beyond the scope of this guide please contact Mi One PS 3 or PS 3E export our Technical Services Group in the following ways version power supply T US customers 888 349 3222 M This user s guide International customers 425 787 3222 M A warranty card from 6 00 am to 4 30 pm Pacific Time Monday through Friday You can register online at E 425 787 3211 www syme
5. a total of 5 years of warranty coverage under the terms and limitations as set forth below without additional cost If you don t register your product you will still receive one year of warranty coverage but it only takes a minute to fill out the card or register online and we won t share your personal information with others Following are the terms and limitations of the Symetrix warranty Warranty Symetrix Inc expressly warrants to the original purchaser Buyer subject to the terms and conditions set forth below that the Product will be free from defects in material and workmanship as a result of normal commercial use for one 1 year from the date of purchase This warranty will be automatically extended subject to the additional limitations set forth below for an additional four years if the Warranty Registration is completed and returned to Symetrix or completed online within thirty 30 days of the date of delivery Symetrix s warranty obligation is limited to the repair replacement or refund at Symetrix s sole discretion of the part or parts of the Product which may thus prove defective in materials or workmanship within one year from date of purchase or five years from the date of purchase if Buyer has registered its purchase as provided above under normal use and which our examination discloses to our satisfaction to be thus defective provided that Buyer gives Symetrix prompt notice of its
6. control voltages of 0 to 10 volts range Stereo signals may be adjusted by one control Rear panel Euroblock connectors accept balanced or unbalanced line level signals user supplied Symetrix 308 VCA Volume Control Loudness EQ User s Guide Making Hardware Connections Overview of Rear Panel Connectors and Controls Fast First Time Setup Controlling Channel Levels From a Potentiometer or Voltage Ramp Controlling Channel Levels By a Variable Resistor Unbalanced Connections Input and Output Connector Wiring Overview of Rear Panel Connectors and Controls Symetrix RAI POWER CONNECT TO INPUT N SYMETRIX 2 9 Caen PSF C 298 SUPPLY ONLY CONNECTION 1 i CTL2 CONNECTOR TYPE WHAT IT DOES POWER INPUT 7 pin DIN Connector Accepts power only from Symetrix PS 3 PS 3E or PY 3 power supply CONTROL PIN Euroblock Connectors ASSIGNMENT Input connections for remote controls RAMP1 Ramp Output 1 Same control voltage applied to CTL1 appears here Use it for controlling channel 1 of multiple 308 units CTL1 Control Input 1 Connect a ramp voltage or the wiper W of a 10k ohm linear taper poten tiometer here for controlling channel 1 audio levels GND1 Control 1 Ground Connect the ramp voltage ground or the CCW low terminal of the pot connected to CTL1 here 10V 10 VDC Output Provides the 10 VDC control voltage for 10k ohm lin
7. warranty claim and satisfactory proof thereof Symetrix will make every reasonable effort to ensure that parts are available to support the repair of our products under warranty In the event that a product or component part thereof becomes obsolete unavailable or irreparable Symetrix reserves the right to refund a prorated portion of the purchase price in full satisfaction of all warranty claims A refund of the purchase price is prorated as follows 100 through year one 80 through year two 60 through year three 40 through year four and 20 through year five In order to serve you better we request that the Buyer shall prior to shipping Product to Symetrix for warranty service contact Symetrix and secure a Return Authorization Number that shall be included with the returned Product This will facilitate our efforts to keep track of your Product and process your warranty repair as quickly as possible Buyer will prepay all freight charges to ship the Product to Symetrix for warranty inspection and service This warranty is subject to Symetrix s inspection of the Product at its facilities and upon Symetrix s request satisfactory proof of purchase dated copy of original retail dealer s invoice Symetrix reserves the right to effect repairs to the product with reconditioned components parts Products once repaired under warranty will be shipped to Buyer freight prepaid by Symetrix via United Parcel Service surfa
8. CA DC CONTROL 10V REF REMOTE LEVEL VCA CONTROL DC CONTROL RAMP gt OUT d B Symetrix 308 VCA Volume Control Loudness EQ User s Guide Troubleshooting D SYMPTOM PROBABLE CAUSE WHAT TO DO No output Check cables and connections to see if e Inputs are driving outputs and outputs are driving inputs e That there is a signal from the source and that it is getting to the 308 Check if unit is plugged in Hum or buzz in output Check input and output connector wiring Check for ground loop problem Inspect related system equipment ground ing to see that all system components are on the same AC ground Distortion Check input signal Check if line input signal may be too hot If using a high setting for your maximum audio level you may be overload ing the input to your amplifier lower the audio level Check if something else is clipping in the signal chain Noise hiss Check input signal levels The 308 is intended to operate at or near line level 4dBu is nominal Make sure that the signal you are feeding to the 308 is a line level signal not mic level Check that all systems components are on the same AC ground Check gain settings on upstream equipment The system gain structure should be such that the 308 receives 4dBu nominal signal No LED display Check if unit is plugged in Verify that AC outlet works 13 Symetrix 308 VCA Volume Control Loudness E
9. Delay F x Machine Broadcast Audio Delay Digital Voice Processor 2x2 DSP Engine 628 Remote Control 440 Remote Control Remote Control Symetrix www symetrixaudio com
10. Q User s Guide Hardware Specifications Input Output Maximum Input Level Maximum Output Level Input Impedance Output Impedance Input Common Mode Rejection 20 dBu balanced 20 dBu unbalanced 22 dBu balanced 18 dBu unbalanced gt 20k ohms balanced gt 10k ohms unbalanced 200 ohms balanced 100 ohms unbalanced gt 40 dB Performance Data Frequency Response THD N Residual Output Noise Gain Control Equalization 20 Hz to 20 kHz 0 0 5 dB with no equalization applied 20 Hz to 20 kHz 0 1 5 dB at unity gain with max EQ depth lt 0 025 at unity gain O dBu in out 95 dBu typical at unity gain O dB unity to 65 dB 15 dB max 1 kHz Analog Control Control inputs accept any of Gain Ramp Out Auxiliary Power Out a 10k linear rheostat to ground b 10k linear potentiometer from 10 reference output to ground c O to 10 VDC control voltage d Symetrix RC 3 Remote Control Unity at 10 VDC and max attenuation at 0 VDC Buffered duplicate of the Control In voltage 24 VDC 10 100 milliamps max continuous load Connections Inputs Outputs Control Ports Euroblock AC Power In 7 pin DIN Physical Size H x W x D Shipping Weight 1 2 rack unit 1 75 in x 8 5 in x 6 5 in 4 445 cm x 21 59 cm x 15 875 cm 4 5 Ibs Electrical Power Requirements PS 3 PS 3E 12W maximum Symetrix PS 3 or PS 3E only 115V 60 Hz AC nominal 230V 50 to 60 Hz AC nominal In the
11. ce or any similar shipper to any location designated by buyer within the Continental United States At Buyer s request and expense Product will be returned via airfreight Outside the continental United States repaired or replaced products will be returned freight collect THIS WARRANTY IS EXPRESSLY IN LIEU OF ALL OTHER WARRANTIES EXPRESS OR IMPLIED ARISING BY LAW OR OTHERWISE INCLUDING WITHOUT LIMITATION ANY OBLIGATIONS OF THE SELLER WITH RESPECT TO CONSEQUENTIAL DAMAGES INCLUDING THE WARRANTIES OF MER CHANTABILITY AND FITNESS FOR USE AND OF ALL OTHER OBLIGATIONS OR LIABILITIES ON OUR PART AND WE NEITHER ASSUME NOR AUTHORIZE ANY OTHER PERSON TO ASSUME FOR US ANY OTHER LIABILITY IN CONNECTION WITH THE SALE OF THE PRODUCT THIS WARRANTY SHALL NOT APPLY TO THIS PRODUCT OR ANY PART THERE OF WHICH HAS BEEN SUBJECT TO ACCIDENT NEGLIGENCE ALTERATION ABUSE OR MISUSE WE MAKE NO WARRANTY WHATSOEVER IN RESPECT TO ACCESSO RIES OR PARTS NOT SUPPLIED BY US THE TERM ORIGINAL PURCHASER AS USED IN THIS WARRANTY SHALL BE DEEMED TO MEAN THAT PERSON OR COMPANY THAT ORIGINALLY PURCHASED THE PRODUCT This Symetrix product has been designed and manufactured for use in professional and studio audio systems and is not intended for other usage This warranty only applies to Buyers using the Product in professional and studio audio systems With respect to others including but not limited to consumers for personal family o
12. e sentative Pack the unit in its original packaging materials Include your name address daytime telephone number and a brief statement of the problem Write the RA number on the outside of the box Ship the unit to Symetrix freight prepaid We do not accept freight collect shipments Symetrix Inc 14926 35th Ave West Lynnwood WA 98037 If You Don t Have Factory Packaging Materials If you send us your product in substandard packaging we will charge you for factory shipping materials If you don t have the factory packaging materials do the following 1 2 3 Select an oversized carton Wrap the unit in a plastic bag and surround it with bubble wrap Pack the box full of Styrofoam peanuts Be sure there is enough clear ance in the carton to protect the rack ears We will return the unit in Symetrix packaging 17 Symetrix 308 VCA Volume Control Loudness EQ User s Guide Declaration of Conformity We Symetrix Inc 14926 35th Avenue West Lynnwood Washington USA declare under our sole responsibility that the product 308 VCA Volume Control Loudness EQ to which this declaration relates is in conformity with the following standard EN 55103 2 Electromagnetic Compatibility Product Family Standard for Audio Video and Entertainment Lighting Control Apparatus for Professional Use Part 2 Immunity PS 3E power supply complies with this code EN 60065 Safety Requirements for Mains Operated Elect
13. e to a balanced signal and boost the 10 dBV signal to the 4 dBu level If you experience hum or noise make sure that both the 308 and the device with the unbalanced output are grounded on the same AC mains circuit If this is not the source of the noise problem isolate the balanced input from the unbalanced output using a Symetrix 303 or 307 10 Symetrix 308 VCA Volume Control Loudness EQ User s Guide Making Hardware Connections Overview of Rear Panel Connectors and Controls Fast First Time Setup Controlling Channel Levels From a Potentiometer or Voltage Ramp Controlling Channel Levels By a Variable Resistor Unbalanced Connections Input and Output Connector Wiring Input and Output Connector Wiring METHOD CONNECTOR CHANNEL Balanced Terminal Strip Balanced Female XLR Pin 1 Circuit Ground Pin 2 High Pin 3 Low Balanced TRS Plug Tip High Ring Low Sleeve Shield Unbalanced TS Plug Tip High Sleeve Low Shield Unbalanced RCA Plug Tip High Sleeve Low Cable Shield Not Connected Balanced Male XLR Pin 1 Circuit Ground Pin 2 High Pin 3 Low Unbalanced TS Plug Tip High Sleeve Shield Wire Low Not Connected Input Input Input Input Input Output Output Symetrix 308 VCA Volume Control Loudness EQ User s Guide LEVEL VCA BALANCED OUTPUT SUBTRACT BALANCED INPUT BANDPASS EQ VCA FILTER DEPTH EQ V
14. ear taper potentiometer s Connect the pot terminal CW high here If using a control pot for each channel connect the CW terminals from two pots here GND2 Control 2 Ground Connect the ramp voltage ground or the CCW low terminal of a 10k ohm linear taper potentiometer here for controlling channel 2 audio levels CTL2 Control Input 2 Connect a ramp voltage or the wiper W of the pot connected to GND2 here RAMP2 Ramp Output 2 Same control voltage applied to CTL2 appears here Use it for controlling channel 2 of multiple 308 units GND Ground Provides ground connection for 24 VDC connections 24V 24 VDC Output Provides 24 VDC power for remote controls requiring it Wi Symetrix 308 VCA Volume Control Loudness EQ User s Guide Making Hardware Connections Overview of Rear Panel Connectors and Controls Fast First Time Setup Controlling Channel Levels From a Potentiometer or Voltage Ramp Controlling Channel Levels By a Variable Resistor Unbalanced Connections Input and Output Connector Wiring Overview of Rear Panel Connectors and Controls continues CONNECTION CONNECTOR TYPE D WHAT IT DOES EQ DEPTH Trimpots 1 and 2 Controls the amount of loudness EQ compensation applied to their respec tive audio channels They are set for maximum loudness contour from the factory maximum mid range attenu ation Can be independently ad justed Once adjusted
15. g The chassis of this product is grounded through the grounding conduc tor of the PS 3 or PS 3E power cord To avoid electric shock plug the power cord into a properly wired receptacle before making any connections to the product A protective ground connection by way of the grounding conductor in the power cord is essential for safe operation Do not defeat the safety purpose of the grounding plug The grounding plug has two blades and a third grounding prong The third prong is provided for your safety When the provided plug does not fit your outlet consult an electrician for replacement of the obsolete outlet Danger from Loss of Ground If the protective ground connection is lost all accessible conductive parts including knobs and controls that may appear to be insulated can render an electric shock Proper Power Cord Use only the power cord and connector specified for the product and your operating locale Use only a cord that is in good condition Protect the power cord from being walked on or pinched particularly at the plug convenience receptacle and the point where the cord exits from the apparatus Operating Location Do not operate this equipment under any of the following conditions explosive atmospheres in wet locations in inclement weather improper or unknown AC mains voltage or if improperly fused Do not install near any heat source such as radiators heat registers stoves or other apparatus includin
16. g amplifiers that produce heat Unplug this apparatus during lightning storms or when unused for long periods of time Stay Out of the Box To avoid personal injury or worse do not remove the product covers or panels Do not operate the product without the covers and panels properly installed Only use accessories specified by the manufacturer Clean only with a damp cloth User serviceable parts There are no user serviceable parts inside the 308 In case of failure refer all servicing to the factory Servicing is required when the 308 has been damaged in any way such as when a power supply cord or plug is damaged liquid has been spilled or objects have fallen into the apparatus the apparatus has been exposed to rain or moisture does not operate normally or has been dropped Equipment Markings CAUTION RISK OF ELECTRIC SHOCK DO NOT OPEN TO REDUCE THE RISK OF FIRE OR WARNING Electric SHOCK DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE RISQUE DE CHOC ELECTRIQUE AVIS NE PAS OUVRIR SEE OWNERS MANUAL VOIR CAHIER D INSTRUCTIONS No user serviceable parts inside Refer servicing to qualified service personnel Il ne se trouve a l interieur aucune piece pourvant entre repar e l usager S adresser a un reparateur comp tent The lightning flash with arrowhead symbol within an equilateral triangle is intended to alert the user of the presence of uninsulated dangerous voltage within the prod
17. interest of continuous product improvement Symetrix Inc reserves the right to alter change or modify these specifications without prior notice 14 Symetrix 308 VCA Volume Control Loudness EQ User s Guide Architects and Engineers Specifications The VCA volume control loudness EQ Shall provide two channels of remote level adjustment and automatic loudness EQ compensation for controlling a stereo signal in one zone or mono signals in two zones There Shall be a voltage controlled amplifier VCA in each channel controlled by either a 0 to 10 VDC ramp signal or by a 10k ohms linear taper potenti ometer or other compatible remote control such as the Symetrix RC 3 Potentiometers may be located up to 500 feet from the VCA volume controller The loudness EQ will be flat at full volume and the output gain will be at unity At lower volumes the loudness EQ shall automatically effectively boost the bass and treble frequencies by lowering the midrange response The maximum midrange attenuation will be 15 dB 1 kHz The VCA volume control loudness EQ Shall provide two balanced line level audio inputs on Euroblock connectors The input impedance shall be at least 20k ohms balanced 10k ohms unbalanced The maximum input level Shall be 20 dBu balanced 20 dBu unbalanced There shall be two balanced line level audio outputs on Euroblock connectors The output impedance shall be 400 ohms bal anced 200 ohms unbalanced The ma
18. ne level audio inputs and outputs to the AUDIO IN and AUDIO OUT Euroblock connectors 2 Connect your remote controls to the CONTROL Euroblock connec tors If using a potentiometer see in this section Controlling Both Channels from a Single Potentiometer If using a rheostat see Controlling Channel Levels By a Variable Resistor 3 Connect the external power Supply to the 308 unit then plug the power supply into an AC outlet 4 Apply line level audio signal to the inputs 5 Adjust the remote controls to maximum level Then set your system power amp levels to the desired maximum level As you adjust the remote controls the 308 passes audio signals At full volume setting the 308 is at unity gain 6 Turn down the remote controls to the lowest listening level you expect the system to be oper ated at 7 The EQ DEPTH trimpots are set for maximum loudness contour from the factory At the lowest VCA setting the EQ DEPTH is 15 dB 1k Adjust the trimpots counterclockwise if you want less EQ response To turn off this feature turn the trimpots completely counterclockwise gt Fast Setup is complete Basic Remote Setup Showing One Channel Symetrix CONTROL EQ DEPTH AUDIO OUT AUDIO IN 1 2 1 2 VOLUME CONTROL POTS 10K OHMS LINEAR TAPER RAMP1 GND1 GND2 RAMP2 24V R GND 1 2 h gt th tih th CONNECT TO a SYMETRIX CE SUPPLY ONLY CHANNEL 1 Control Voltage lt _ 0 to 10V
19. r household use Symetrix expressly disclaims all warranties including but not limited to warranties of merchant ability and fitness for a particular purpose and the express warranties as otherwise provided herein Symetrix reserves the right to modify the design or make additions to or improve ments to its product lines without making similar upgrades to Product purchased by Buyer Symetrix does not authorize any third party including any dealer or sales representative to assume any liability effect any repairs or modifications to the Product or make any additional warranties or representation regarding the Product or Product information on behalf of Symetrix Symetrix s total liability on any claim whether in contract tort including negligence or otherwise arising out of connected with or resulting from the manufacture sale delivery resale repair replacement or use of Product will not exceed the purchase price of the Product or any part thereof which gives rise to the claim In no event will Symetrix be liable for any incidental or consequential damages including but not limited to damage for lost revenue cost of capital claims of customers for service interrup tions or failure to supply and costs and expenses incurred in connection with labor overhead transportation installation or removal of products or substitute facilities or supply houses as a result of Product failure This limited warranty gives B
20. ronic and Related Apparatus for Household and Similar General Use The technical construction file is maintained at Symetrix Inc 14926 35th Avenue West Lynnwood WA 98037 2303 USA The authorized representative located within the European Community is World Marketing Associates P O Box 100 St Austell Cornwall PL26 6YU UK Date of issue May 30 2000 Place of issue Lynnwood Washington USA Authorized signature Dane Butcher President 18 301 302 303 304 305 306 307 308 372 402 420 421M 422 440 450 501 501 01 506E 527E 528E 531E 532E 533E 551E 552E 562E 565E 571 571S 572 581E 606 610 628 9022 RC 1 RC 2 RC 610 Low Distortion Compressor Limiter Dual Microphone Preamplifier Interface Amplifier Headphone Amplifier Distribution Amplifier 1x4 Preamp Ducker Dual Isolation Transformer VCA Volume Control Loudness EQ SPL Computer Dual Output Delay Stereo Power Amplifier AGC Leveler Stereo AGC Leveler Foreground Audio Controller Dual Zone Priority Mixer Peak RMS Compressor Limiter Peak RMS Compressor Limiter Headphone Amplifier Voice Processor Voice Processor Graphic Equalizer Graphic Equalizer Graphic Equalizer 5 Band Parametric EQ Dual 5 Band Parametric EQ Windowing Expander Gate Dual Compressor Limiter Expander SPL Computer SPL Computer Slave SPL Computer Distribution Amplifier 4x4
21. the amount of EQ compensation follows the volume set by the remote controls At full volume 10V control voltage the EQ response is flat and the 308 gain is at unity the 308 will not add gain to your system At lowered volume the midrange response is reduced to a maximum of 15 dB 1 kHz effectively boosting the bass and treble frequencies Turning these trimpots counterclock wise lessens the amount of loudness EQ compensation Turning these trimpots fully counter clockwise turns off the EQ DEPTH feature AUDIO OUT Euroblock Connectors Provides balanced line level audio output signals for their respective channels Use 2 conductor shielded cable for all connections AUDIO IN Euroblock Connectors Connect balanced line level input signals to these connectors for their respective channels Use 2 conductor shielded cable for all connections For balanced use the 308 follows AES standards for balanced audio circuits For unbalanced use see in this section Unbalanced Connections Input and Output Connector Wiring Symetrix 308 VCA Volume Control Loudness EQ User s Guide Making Hardware Connections Overview of Rear Panel Connectors and Controls Fast First Time Setup Controlling Channel Levels From a Potentiometer or Voltage Ramp Controlling Channel Levels By a Variable Resistor Unbalanced Connections Input and Output Connector Wiring Fast First Time Setup 1 Connect your li
22. trixaudio com When you register the 308 you tech symetrixaudio com get 4 extra years of warranty www symetrixaudio com coverage Optional Rackmount Accessories MODEL ITEM DESCRIPTION RM 3 19 Rackmount Tray IU in height FP 3 Filler Panel Covers unused space when one 308 unit is mounted in the rack tray PY 3 Y Power Cable Connects a 308 with another 300 Series product to the same power supply RC 3 Remote Control For use with the 308 unit Contact your dealer or Symetrix for purchasing information Notational Conventions in this User Guide Note Identifies information that needs extra emphasis Generally supplies extra information to help you to better use the 308 CAUTION Identifies information that if unheeded may cause damage to the 308 or other equipment in your system WARNING Identifies information that if ignored may be hazardous to your health or that of others CAPS Controls switches or other markings on the chassis of the 308 Symetrix 308 VCA Volume Control Loudness EQ User s Guide Before You Begin What Ships in the Box Getting Help Optional Rackmount Accessories Notational Conventions in this User Guide Operator Safety Summary Equipment Markings Operator Safety Summary Follow all warnings and instructions Install in accordance with the manufacturer s instructions Power Source This product is intended to operate from a Symetrix PS 3 or PS 3E power supply Groundin
23. u do not need a connection to the 10V terminal Use this setup when you need a remote output mute Connecting a normally open mute push button or relay contact in parallel with the control resistance results in maximum attenuation when the switch contacts are closed The 308 is not damaged by such a connection To use two rheostats to control each channel Symetrix CONTROL EQ DEPTH AUDIO OUT AUDIO IN VOLUME CONTROL POTS 10K OHMS LINEAR TAPER 1 2 A E a T 1 POWER EN e TEET e 60 aR ce a en SUPPLY ONLY ek lol ee ei ints e e o c9 CHANNEL 1 CHANNEL 2 T S 19 i Mute oo Mute 3 3 Rheostat J UU 1 1 JUU eo SOW W W CCW 9 etrix VOLUME peels one LINEAR TAPER EQ 7 F PTH RAMP1 GND1 GND2 RAMP2 24V CONNECT TO INPUT G SYMETRIX D i OR PS 3E D 0R WER SUPPLY ONLY AUDIO OUT AUDIO IN 1 2 1 2 h gt h h h CTL1 1 i T I Jumper connects RAMP1 and CTL2 Rheostat RHEOSTAT PIN CONNECTION TO THE 308 PINS Rheostat Pins 308 Channel 1 Pins 308 Channel 2 Pins W Wiper CTL1 CTL2 CCW low GND1 GND2 Symetrix 308 VCA Volume Control Loudness EQ User s Guide Making Hardware Connections Overview of Rear Panel Connectors and Controls Fast First Time Setup Controlling Channel Levels From a Potentiometer or Voltage Ramp Controlling Channel Levels By a Variable Resistor Unbalanced Connections Input and Outp
24. uct s enclosure that may be of sufficient magnitude to constitute a risk of electric shock to persons The exclamation point within an equilateral triangle is intended to alert the user of the presence of important operating and maintenance servicing instructions in the literature accompanying the product i e this user guide CAUTION To prevent electric shock do not use the polarized plug supplied with the unit with any extension cord receptacle or other outlet unless the blades can be fully inserted Symetrix 308 VCA Volume Control Loudness EQ User s Guide Product Summary The Symetrix 308 VCA Volume Control Loudness EQ provides remote level control and loudness EQ for engineered sound systems You set the amount of loudness EQ compensa tion by adjusting rear panel EQ DEPTH trimpots These circuits may be defeated entirely by turning the trimpots fully counter clockwise The 308 is a half rack unit that fits on a shelf next to a mixer amp or mounts in a rack with optional Symetrix RM 3 308 Product Information Product Summary Features Features Zone Operation Loudness EQ Circuit Remote Level Control Audio Inputs amp Outputs Control the volume of a stereo signal in a single zone or mono signals in two zones Enhances program frequency re sponse as volume is lowered Volume control by use of Symetrix RC 3 Remote Control linear potenti ometers located up to 500 ft from unit or DC
25. ut Connector Wiring Unbalanced Connections We do not recommend unbalanced input and output connections but follow these instructions if you must do so Unbalanced Audio Output Connections 1 Connect the terminal of the 308 to the or high of the unbalanced input connector 2 Make no connection to the terminal of the 308 3 Connect the cable shield to the ground of the 308 and at the unbalanced input connector Notes The output signal level of the 308 will be 6 dB lower when driving an unbalanced input without a transformer or matching interface device To avoid this use the Symetrix 303 Interface Amplifier or 307 Dual Isolation Transformer If you experience hum or noise make sure that both the 308 and the device with the unbalanced input are grounded on the same AC mains circuit If this is not the source of the noise problem isolate the balanced output from the unbalanced input using the Symetrix 303 or 307 Unbalanced Audio Input Connections 1 Connect the incoming signal or high to the terminal of the 308 2 Connect the incoming signal ground to the terminal of the 308 3 Connect the cable shield to the ground connection of the 308 only leave the other end unconnected Notes The 308 is designed to operate at the 4 dBu level If the unbalanced output s of the device feeding the 308 is 10 dBV semi pro or consumer level use the Symetrix 303 Interface Amplifier to convert the unbalanced sourc
26. uyer certain rights Buyer may have additional rights under applicable law 16 Symetrix 308 VCA Volume Control Loudness EQ User s Guide Where to Get Service If ouside of the USA If you have determined that your 308 requires repair services and you live outside of the United States please contact your local Symetrix dealer or distributor for instructions on how to obtain service If inside the USA Symetrix will perform in warranty or out of warranty service on any product it has manufactured for a period of five years from date of manufacture If you reside in the USA then proceed as follows In Warranty Repairs Repairs made in warranty will cost you only one way freight charges We ll prepay the return surface freight Of course if the repair is due to operator error parts and labor will be charged If there are charges for the repair costs you will pay for the return freight All charges will be COD unless you have made other arrange ments prepaid Visa or Mastercard Out of Warranty Repairs If the warranty period has passed you ll be billed for all necessary parts labor packaging materials and freight charges D Service To Get Your 308 Unit Repaired US Customers Only Call our Customer Service Department for a return authorization RA number 888 349 3222 Monday through Friday 6 00 am to 4 30 pm Pacific Time Have your serial number ready to give to the customer service repr
27. ximum output level shall be 22 dBu balanced 18 dBu unbalanced Screwdriver adjustable trimpots shall be provided for selecting the amount of loudness EQ compensation for each channel Nine inputs for remote control connections shall also be provided on Euroblock connectors These inputs shall consist of Ramp Out Control In Ground for each channel 10 VDC Out Ground 24 VDC Out A front panel power indicator shall be provided The frequency response shall be 0 0 5 dB measured between 20 Hz and 20 kHz THD N shall be less than 0 025 measured at unity gain Power consumption shall be 12W maximum The unit shall occupy half of the width of one rack space The physical dimensions shall be 1 75 in H x 8 5 in W x 6 5 in D 4 445 cm H x 21 59 cm W x 15 875 cm D D The VCA volume control loudness EQ shall operate by means of a Symetrix PS 3 connected to 115 VAC nominal 95 130 VAC 60 Hz or a Symetrix PS 3E connected to 230 VAC nominal 165 255 VAC 50 to 60 Hz The VCA volume control loudness EQ Shall be a Symetrix model 308 VCA Volume Control Loudness EQ 15 Symetrix 308 VCA Volume Control Loudness EQ User s Guide Warranty Important Information Regarding Your Warranty We would like to offer you an incentive to complete our product registration form Either fully complete and mail your product registration card or register online at www symetrixaudio com You will then have
Download Pdf Manuals
Related Search