Telex Communications Forum FOH, User Manual

Page 1: ...515 Fax 44 0 1562 745371 Email info uk telex com Website www ddaconsoles com Forum FOH User Manual Telex Communications UK Limited In line with the company s policy of continual improvement specifications and function maybe subject to change without notice This Operator Manual was correct at the time of writing E OE ...

Page 2: ...1 MODULE DESCRIPTIONS 16 MONO INPUT MODULE 18 MONO MUTE INPUT 23 STEREO INPUT MODULE 25 THE STEREO MUTE INPUT MODULE 31 THE DUAL EFFECT RETURN MODULE 32 6 INTO 1 MICROPHONE INPUT 34 THE DIGITAL STEREO INPUT MODULE 36 10 WAY SELECTOR MODULE 41 THE STANDARD OUTPUT MODULE 44 THE MATRIX OUTPUT MODULE 49 COMPOSER OUTPUT MODULE 53 STEREO MASTER MODULE 57 GENERAL SERVICING 61 POWER SUPPLY 62 ...

Page 3: ...Low Voltage Directive and the manufacturer has applied the following standardsQ EN 55013 Q 1990 Limits and methods of measurement of radio disturbance characteristics of Broadcast Receivers and Associated Equipment EN 50082 1 Q 1992 Electromagnetic Compatibility Generic Immunity Standard Part 1 Residential commercial and light industry EN 60065 Q 1994 Safety requirements for mains operated electro...

Page 4: ...stereo mute input dual effect return digital stereo input 10 way selector 6 into 1 microphone module The Forum is normally supplied as a FORUM P A or as a FORUM MATRIX and the frame will accommodate up to 60 modules Normally the master module a double blank module and the 8 output modules will occupy 12 of those positions with the remainder being available for input modules An 8 module wide frame ...

Page 5: ...re not to use your console under such conditions Before powering up the console make sure that the power supply voltage selection matches the local mains supply Never connect or disconnect the power cable with out switching off the power supply Similarly switch of the console before removing or servicing modules Do not attempt to wipe clean the console with a cleaning liquid Most surfaces can be s...

Page 6: ...mains or during thunder storms switch off the power supply and unplug it from the mains supply CABLES This product should only be used with high quality screened twisted pair audio cables terminated with metal bodied 3 pin XLR connectors The cable shield should be connected to Pin 1 Any other cable type or configuration for the audio signals may result in degraded performance due to electromagneti...

Page 7: ...age and or freight charges must be prepaid This Warranty shall only be available ifQ i The Equipment has been properly installed in accordance with the instructions contained in this manual ii The End User has notified the Distributor or DDA in writing within 14 days of the defect appearing iii No persons other than authorised representatives of DDA or the Distributor have effected any replacement...

Page 8: ...onsequential costs damages or losses Pincluding loss of business profits operating time or otherwise arising out of the use or inability to use the product whether or not the likelihood of damage was advised to DDA or its distributor Fuses and lamps are specifically excluded from this warranty This notice does not affect your statuatory rights Benefit of this Warranty may not be assigned by the En...

Page 9: ... 20kHz 0 20dB Line Input to Mix Output 20Hz 0 50dB Pgain 0dB 20kHz 0 20dB Noise DIN Audio Weighted Microphone Input Gain 55dB EIN Ref 200 Ohm S 127 5dBu Line Input to Mix Output Gain 0dB 16 inputs routed S 84dBu Distortion Microphone Input to Mix Output 50dBu input 4dBu output S0 005 Line Input to Mix Output 4dBu input 4dBu output S0 005 Crosstalk Adjacent Channel 1kHz S 100dBu Group to Mix 1kHz S...

Page 10: ...age Q 250mS Accuracy Prelative to 0dB 0 5dB Forum Power Supply specifications AC Mains Voltage selectionQ Internal link settings for 90V 100V 120V 220V 230V and 240V Power Consumption Pmax Q AC Mains frequency Q 50Hz 60Hz Fuse ratingsQ 220 230 240V 6 3A 90 100 120V 10A Cooling MethodQ Internal fan DC Power OutputsQ 17 Volts 6A max 17 Volts 6A max 48 Volts 0 35A max ...

Page 11: ...ndently of the main faders They are used to provide special mixes to artistes as they are recording Pnormally called FOLDBACK or as a signal to be sent to an effect such as a reverberation or delay device BUS This is the term used to describe the summing or mixing of a number of signals A number of signals routed to the same bus will appear as one signal at the output of the bus mixing amplifier B...

Page 12: ... the following stage if it is moving and the signal is moving in the same way then no net signal results GROUP OUTPUT An output usually routed to a multi track tape recorder input This output is derived from a bus and one group output stage is required for each bus PDMR12 excepted HF High Frequency HIGH PASS FILTER A filter which cuts out frequencies below its operating frequency It can be used to...

Page 13: ...ereo output section which controls the level of the stereo mix and associated functions such as monitoring MIX PATH The path used by the signal going to the stereo mix PARAMETRIC EQ An equaliser section which has variable frequency level and Q PAN A pan control or Pan Pot or Panoramic Potentiometer is used to spread a mono signal across a stereo bus In the centre the signal is reduced by 4 5dB to ...

Page 14: ... balanced instead a bus common is used to pick up any interference which will also be picked up by the true bus The interference then appears as a common mode signal at the mixing amplifier RETURN Any signal that is sent out of the console and is returned after some form of processing ROUTING The sending of a signal to a bus normally by pressing a switch Signal can be routed to several buses simul...

Page 15: ...ten used with peaking equalisers but it can also be used to determine the roll off point of shelving EQs as well VCA Voltage Controlled Amplifier An amplifier whose gain can be controlled by a DC Voltage applied to its control port XLR The XLR Pin fact a specific manufacturer s model reference is an industry standard connector of high quality and is normally used for balanced signals primarily mic...

Page 16: ... ve Send Hot P ve Ring Cold Return Ground Sense Sleeve Ground Ground Ground Blanking panels are fitted to the main chassis to allow the fitting of multiway connectors Consult your authorised dealer for more information All balanced XLR inputs are wired to the international standard of Pin 2 HOT If you need to connect unbalanced equipment to inputs or outputs wire the cold terminal to Pin 3 for XLR...

Page 17: ...may be adjusted from 10dB to 20dB corresponding to a sensitivity of 14dBu to 16dBu to give an output of 4dBu at the stereo mix outputs The impedance of the line input is approximately 20Kohms so instruments with high impedance outputs such as electric guitars are best fed through a DI box to the microphone input to avoid being loaded down by the line input impedance ...

Page 18: ...is active on both Mic and Line Inputs On Mic the gain can be adjusted from 6dB to 76dB For Line inputs the adjustment is from 10dB to 20dB LINE The LINE switch selects the signal on the line input socket to feed the channel path when it is down In this case the Mic signal is disconnected The PHASE REVERSE switch inverts the phase of the selected input Mic or Line to allow compensation for differen...

Page 19: ...roviding 15dB of gain at 12kHz HI MID Peaking section providing 15dB of gain at frequencies from 470Hz to 15kHz LO MID Peaking section providing 15dB of gain at frequencies from 70Hz to 2 2kHz LF Shelving section providing 15dB of gain at 50Hz EQ IN The EQ switch inserts the entire equaliser circuit into circuit When switched out the equaliser is totally bypassed keeping the signal path to a minim...

Page 20: ... 2 controls with a signal taken pre fader instead of post fader In this case the signal on the Aux 1 2 buses is unaffected by the position of the channel fader AUX 2 Controls the level of the channel signal fed to the Aux 2 bus This signal is normally post fader unless the PRE button just above is depressed AUX 3 Controls the level of the channel signal fed to the Aux 3 bus and is internally linka...

Page 21: ...led in the switch when the channel is active When OFF all post fade auxiliary sends and routing assignments are muted PFL The PFL button Por SOLO feeds the post EQ pre fader signal to the Monitor section Ploudspeakers or headphones replacing the selected monitor source The main stereo output of the console is not affected The red led in the PFL switch will illuminate when the PFL function is activ...

Page 22: ...nal Input LevelQ 16dBu to 14dBu Tip Q Signal ve PHot Ring Q Signal ve PCold Sleeve QGround Input Impedance Q 10 kOhm Insert Point Q 1 4O TRS Jack Socket ëAí Gauge Unbalanced Nominal Input Output levelQ 2dBu Tip Q Insert Send Ring Q Insert Return Sleeve QGround Output ImpedanceQ S75 Ohm Input Impedance Q 10 kOhm Direct Output Q1 4O TRS Jack Socket ëAí Gauge Ground Compensated Nominal Output levelQ ...

Page 23: ...are available to further select the prefade signal between the pre and post equaliser signal AUXILIARIES 5 and 6 Independent level control is provided for these two auxiliaries with a common switch to select the prefade signal as the source Internal jumpers are available to further select the prefade signal between the pre and post equaliser signal ROUTING Independent routing is provided to the 8 ...

Page 24: ...nal Input LevelQ 16dBu to 14dBu Tip Q Signal ve PHot Ring Q Signal ve PCold Sleeve QGround Input Impedance Q 10 kOhm Insert Point Q 1 4O TRS Jack Socket ëAí Gauge Unbalanced Nominal Input Output levelQ 2dBu Tip Q Insert Send Ring Q Insert Return Sleeve QGround Output ImpedanceQ S75 Ohm Input Impedance Q 10 kOhm Direct Output Q1 4O TRS Jack Socket ëAí Gauge Ground Compensated Nominal Output levelQ ...

Page 25: ...RIAA adapter GAIN The Gain control is wide range rotary control and is active on both inputs A and B On input A PMic the gain is adjustable from 16 to 66dB while on input B PLine or Phono the gain range is from 10 to 20dB LEFT CUT This switch mutes the left channel signal so only the right channel signal is heard RIGHT CUT This switch mutes the right channel signal so only the left channel signal ...

Page 26: ...ID Peaking section providing 15db of gain at a centre frequency adjustable from 470Hz to 15kHz LO MID Peaking section providing 15db of gain at a centre frequency adjustable from 95Hz to 1 1kHz LF Shelving section providing 15dB of gain at 50Hz Auxiliaries The FORUM console has six Auxiliary buses accessible on the input module via 4 controls On the Stereo Input module the Aux buses are fed from a...

Page 27: ...Aux 2 bus This signal is normally post fader unless the PRE button just above the AUX 2 control is pressed PRE Feeds the AUX 2 control with a signal taken pre fader instead of post fader In this case the signal fed to the Aux 2 bus is unaffected by the position of the channel fader AUX 3 Controls the level of the channel signal fed to the Aux 3 bus and can be linked internally to be pre or post fa...

Page 28: ...ol P 3dB MIX Routes the post fade post bal signal to the stereo mix bus 1 2 Routes the post fade post bal signal to output buses 1 and 2 3 4 Routes the post fade post bal signal to output buses 3 and 4 5 6 Routes the post fade post bal signal to output buses 5 and 6 7 8 Routes the post fade post bal signal to output buses 7 and 8 BAL When BAL is set to its centre equal levels are sent to both buse...

Page 29: ...put is not affected The red LED in the PFL switch illuminates when the PFL function is active PFL signals from different sources that are active simultaneously are summed SIGNAL METER PLED A five segment LED signal meter shows when a signal is present above a threshold of 13dBu and will show peak signals of up to 17dBu If the top led is on partly or continuously the signal is close to clipping The...

Page 30: ...3 Q Signal ve PCold Pin 1 QGround Input Impedance Q 2kOhm InputBQLineQ1 4O TRS Jack Socket ëAí Gauge balanced Nominal Input levelQ 16dBu to 14dBu Tip Q Signal ve PHot Ring Q Signal ve PCold Sleeve Q Ground Input ImpedanceQ 10 kOhm Input B can also accept Phono PRIAA signals with the optional RIAA card fitted RIAA Input sensitivity Q 2mV at maximum gain RIAA Input Impedance Q 47 kOhm 100pF ...

Page 31: ...es These switches assign the channel to one or more mute groups and will cause the channel to CUT if the master cut for the assigned mute group is operated The mute groups do not have to be the same as the audio groups and great flexibility can be achieved by having different assignments A SAFE switch is provided to prevent a channel from responding to a master cut while retaining the assignment ...

Page 32: ...F Provides 15dB of gain at 50Hz for low frequency equalisation AUX 1 AUX 2 The controls determine the level of signal sent to auxiliaries 1 and 2 The signal will normally be Pre fade Post EQ but internal links allow either Pre fade Pre EQ or Post Fader to be selected AUX 3 AUX 4 Similar to AUX 1 and 2 but the default signal is Post fader Internal links allow the Pre fade Post EQ and Pre fade Pre E...

Page 33: ... type Balanced Nominal Input LevelQ 16dBu to 14dBu Pin 2 Q Signal ve PHot Pin 3 Q Signal ve PCold Pin 1 QGround Input Impedance Q 10 kOhm Line Input Q TRS Jack Socket ëAí Gauge Balanced Nominal Input LevelQ 16dBu to 14dBu Tip Q Signal ve PHot Ring Q Signal ve PCold Sleeve QGround Input Impedance Q 10 kOhm ...

Page 34: ...f the module SIG Indicates the presence of signal above The internal signal level of the module will be about 18dBu when this indicator comes on PEAK Indicates that the signal level is approaching clipping and that the gain should be reduced The internal signal level of the module will be about 12dBu when this indicator comes on The maximum signal level inside the module is 20dBu and thus about 6d...

Page 35: ...D MAINTENANCE MANUAL 9601 PAGE 35 CONNECTORS AND PIN DEFINITIONS Mic Input Q 3 Pin XLR type Balanced Nominal Input LevelQ 72dBu to 2dBu Pin 2 Q Signal ve PHot Pin 3 Q Signal ve PCold Pin 1 QGround Input Impedance Q 2kOhm ...

Page 36: ... possible to internally set which of the inputs is selected when the console is switched on GAIN The gain control is a wide range rotary potentiometer with a range of 30dB so that the different output levels of the sources may be adapted to the input PHONO Selects the Stereo Phono PRIAA equalised input as the source for the channel All other sources are switched off CD Selects the Stereo CD input ...

Page 37: ...cuit When switched out the equaliser is totally bypassed Auxiliaries The Digital Stereo input can feed all 6 auxiliary buses AUX 1 Controls the level of a mono sum of the channel signal fed to the AUX 1 bus This signal is normally post fader unless the PRE button just below the AUX 1 control is pressed AUX 2 Controls the level of the channel signal fed to the AUX 2 bus This signal is normally post...

Page 38: ...3 and 4 to feed Aux buses 5 and 6 ROUTING When any routing button is pressed the BAL control is automatically inserted into circuit allowing the signal to be balanced in the stereo image MIX Routes the post fade post BAL stereo channel signal to the main stereo PLeft Right mix bus 1 2 Routes the post fade post BAL stereo channel signal to group buses 1 and 2 3 4 Routes the post fade post BAL stere...

Page 39: ...L The PFL Por SOLO button feeds the post EQ pre fader signal to the monitor section Ploudspeakers or headphones replacing the master signal The main stereo output of the console is not affected The red led in the PFL switch illuminates when the PFL function is active PFL signals from different sources that are active simulataneously are summed SIGNAL METER A five segment LED signal meter shows whe...

Page 40: ...o Tip Q Signal PHot Phono OuterQ Ground Input Impedance Q 10 kOhm Phono Input PRIAA Q Cinch Phono RCA unbalanced Nominal Input level Q 54dBu to 24dBu Phono Tip Q Signal PHot Phono OuterQ Ground Input Impedance Q 47 kOhm 100pF Digital Input Q Optical Co axial Nominal Input Level Q 28dBFS to 0dBFS Digital Interface Q SPDIF D A Converter Q 18 bit linear Oversampling Q 8 Times ...

Page 41: ...le XLR connectors provide outputs which can then be connected by external cables to the 2 track input of the master module The module could also be used as a 10 way source selector for the stereo input module for example Each button is associated with an identification strip to allow for source labelling An alternative version of this module fitted with female XLR connectors may be used to expand ...

Page 42: ...ESCRIPTION 1 d f 1 LEFT 2 V Z 1 RIGHT 3 K P 2 LEFT 4 C D 2 RIGHT 5 A B 3 LEFT 6 F E 3 RIGHT 7 R L 4 LEFT 8 W s 4 RIGHT 9 b a 5 LEFT 10 h e 5 RIGHT 11 k l 6 LEFT 12 v p 6 RIGHT 13 z u 7 LEFT 14 KK DD 7 RIGHT 15 LL EE 8 LEFT 16 MM F 8 RIGHT 17 JJ NN 9 LEFT 18 CC H 9 RIGHT 19 t y 10 LEFT 20 j n 10 RIGHT ...

Page 43: ...A B F 5 6 C H J 4 D K P V Z 2 3 N T U Y L M S W X 8 R 7 a 10 b e h 9 c d f j 1 n t y 19 20 m s w x l r p v 11 12 k u D D 13 14 z A A E E K K L L 15 B B F F H H M M 16 C C J J N N 17 18 VIEWED FROM SOLDER SIDE All unlabelled pins are bussed as Audio Ground ...

Page 44: ...sert point is provided in the group signal path which allows the connection of external processing devices such as limiter compressor units The Insert connector is on the rear panel of the Group module and plugging in the jack automatically breaks the normal signal path and inserts the external device LED METERING The twenty segment led meter reads the signal present on the Group output or the pre...

Page 45: ...stem The signal feed is taken pre the level control and is therefore unaffected by the position of the return level pot PAN Positions the return signal within the stereo image with a 4 5dB relative drop in the centre RET LEV This is the level control for the return signal and adjusts the amount of level sent to the stereo mix SOLO The return signal may be soloed to the monitoring system This solo ...

Page 46: ...sub group to the mix with an auxiliary send If the console is being used for recording this switch allows A B monitoring of the tape send and track return signals If the PA RECORDING switch is set to Recording the metering will follow the selection of Return or Bus on the input of the return section EQUALISER The two band equaliser features 15dB of gain at 8kHz PHF and 60Hz PLF with a shelving cha...

Page 47: ...ntrol for the return signal and adjusts the amount of level sent to the stereo mix SOLO The return signal may be soloed to the monitoring system This solo signal is pre the return level control The led in the switch illuminates when solo is pushed ON The ON switch enables the Return B signal to the stereo mix bus and has led indication when enabled SUB LEFT This will route the group output signal ...

Page 48: ...ld Pin 1 Q Ground Output Impedance Q S75 Ohm Aux Return Input Q TRS Jack Socket ëAí Gauge Balanced Nominal Input LevelQ 4dBu Por 10dBV Tip Q Signal ve PHot Ring Q Signal ve PCold SleeveQ Ground Input Impedance Q 10 kOhm Insert Point Q TRS Jack Socket ëAí Gauge Unbalanced Nominal Input LevelQ 2dBu Tip Q Insert Send Ring Q Insert Return SleeveQ Ground Output Impedance Q S75 Ohm Input Impedance Q 10 ...

Page 49: ...ay be internally linked to show with either peak or VU characteristics METER MATRIX This button changes the input to the meter from the group signal to the matrix signal EXTERNAL L This control adjusts the level of the External Left input to the matrix bus on the module Pie Bus 1 on Module 1 The sensitivity of this input is internally link selectable to be 4dBu or 10dBV EXTERNAL R This control adj...

Page 50: ...nal by the rotary potentiometer Pressing FADER REVERSE changes the mode so that the fader now controls the MATRIX output with the rotary pot controlling the GROUP output This button has led indication MATRIX LEVEL Adjusts the level of the MATRIX output signal fed to the XLR connector on the rear panel MATRIX ON Enables the matrix output with led indication MATRIX SOLO Feeds the selected post level...

Page 51: ...es the GROUP signal to the main LEFT bus post fader MIX SUB R Routes the GROUP signal to the main RIGHT bus post fader FADER Controls the output level of the GROUP signal unless FADER REVERSE has been pressed when it will control the level of the MATRIX output signal ...

Page 52: ...al Output LevelQ 4dBu Pin 2 Q Signal ve PHot Pin 3 Q Signal ve PCold Pin 1 Q Ground Output Impedance Q S75 Ohm Group Insert Point Q 1 4O TRS Jack Socket ëAí Gauge Unbalanced Nominal Input LevelQ 2dBu Tip Q Insert Send Ring Q Insert Return SleeveQ Ground Output Impedance Q S75 Ohm Input Impedance Q 10 kOhm External Input Q 1 4O TRS Jack Socket ëAí Gauge Unbalanced Nominal Input LevelQ 4dBu Por 10dB...

Page 53: ...peration Only Tape Return 3 is described here AUX 1 Adjusts the amount of Tape 3 signal fed to Auxiliary bus 1 The signal is taken pre or post the level control depending on the position of the PRE POST switch below the AUX 2 control AUX 2 Adjusts the amount of Tape 3 signal fed to Auxiliary bus 2 The signal is taken pre or post the level control depending on the position of the PRE POST switch be...

Page 54: ...frequency equaliser section with gain adjustable by 15dB at a fixed frequency of 80Hz AUX 1 Adjusts the amount of Tape 1 signal fed to Auxiliary bus 1 The signal is taken pre or post the level control depending on the position of the PRE POST switch below the AUX 2 control AUX 2 Adjusts the amount of Tape 1 signal fed to Auxiliary bus 2 The signal is taken pre or post the level control depending o...

Page 55: ... return signal to the monitoring outputs and main stereo meters The feed is internally selectable to be pre or post the level control TAPE Selects the Tape 1 Return signal to the monitoring section instead of the BUS output The led illuminates when TAPE is selected MIX L Routes the BUS Pgroup signal to the stereo mix left channel MIX R Routes the BUS Pgroup signal to the stereo mix right channel F...

Page 56: ... Pin 1 Q Ground Output Impedance Q S75 Ohm Tape ReturnsQ 1 4O TRS Jack Socket ëAí Gauge balanced Nominal Input LevelQ 4dBu P 10dBV Tip Q Signal ve PHot Ring Q Signal ve PCold SleeveQ Ground Input Impedance Q 10 kOhm Group InsertQ 1 4O TRS Jack socket ëAí Gauge unbalanced Nominal Input LevelQ 2dBu Tip Q Insert Send Ring Q Insert Return SleeveQ Ground Output Impedance Q S75 Ohm Input Impedance Q 10 ...

Page 57: ...omatically breaks the normal signal path and inserts the external equipment The Stereo Mix Group and Auxiliary outputs have a nominal operating level of 4dBu with the facility to interface at 10dBV All these main outputs may be fitted with transformers LED Metering The two led bargraph meters follow under normal operating conditions the output of the stereo mix If any SOLO button is pressed they s...

Page 58: ... outputs and the stereo mix for use in global announcements The control room monitor outputs are muted completely when ALL is pressed OSC LEVEL This pot controls the level of the internal tone oscillator which may be used for signal path testing or equipment alignment The oscillator operates at a frequency of 1kHz ON Switches on the oscillator for use as above and routes the oscillator signal to a...

Page 59: ... separate mono output available which is a sum of the stereo mix output and can be taken as a pre or post master fader feed with its own level control PRE When the switch is up the mono sum is taken after the main stereo faders When depressed the signal is taken pre fader so is unaffected by the master fader positions HEADPHONE MON As well as to its own output connector the mono signal can be fed ...

Page 60: ... Gauge Balanced Nominal Input LevelQ 4dBu Por 10dBV Tip Q Signal ve PHot Ring Q Signal ve PCold SleeveQ Ground Input Impedance Q 10 kOhm Insert Points Q 1 4O TRS Jack socket ëAí Gauge Unbalanced Nominal Input levelQ 2dBu Tip Q Insert Send Ring Q Insert Return SleeveQ Ground Output ImpedanceQ S75 Ohm Input ImpedanceQ 10 kOhm Control Room Outputs Q 1 4O TRS Jack socket ëAí Gauge Nominal Output level...

Page 61: ...by pulling carefully up at one end then along unclipping each section very carefully Remove three screws which hold the module in place located at the bottom top and rear near the bottom of the connector panel To remove the module lift the bottom of the panel then pull the module back about 2cms so that the top is disengaged from the frame Unplug the ribbon cable from the module along with any ear...

Page 62: ...the operating voltage set by internal switches There are four internal switches which determine the operating voltage of the unit DO NOT CONNECT THE POWER SUPPLY TO THE MAINS WITHOUT CONFIRMING YOUR VOLTAGE SETTING Use a screwdriver to move the switches to the correct setting The DC output voltages are 17V 17V and 48V The fuse ratings areQ 240 230 220 T3 15A 120 100 90 T6 3A NOTE The PSU has a gro...