Operators & Service Manual XL88 EVI PRO AUDIO GROUP Klark Teknik Building, Walter Nash Road, Kidderminster, Worcestershire DY11 7HJ, England Tel: (01562)741515 Fax: (01562)745371 1
DECLARATION OF CONFORMITY The Directives Covered by this Declaration 89/336/EEC Electromagnetic Compatibility Directive, amended by 92/31/EEC & 93/ 68/EEC Equipment Type Product Name Matrix Mixer XL88 The Basis on which Conformity is being Declared The Products named above comply with the requirements of the above EU directives by meeting the following standards: EN55013: 1990 EN50082: 1992 Signed: ...................
ATTENTION! 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 electromagnetic interference.
CONTENTS INTRODUCTION 8 INSTRUMENT FAMILIARISATION 9 USING THE MIDAS XL88 12 APPLICATIONS 16 AUDIO CONNECTIONS 19 SPECIFICATIONS 20 CIRCUIT DESCRIPTIONS 22 CHANNEL MODULE PFL MIX & OUTPUT MODULE POWER SUPPLY 23 26 28 WARRANTY 31 SERVICE REQUEST FORM 32 SCHEMATIC DIAGRAMS CHANNEL IN/OUT CHANNEL MIX LEVEL PFL MIX & OUTPUT CHANNEL IN/OUT METER SECTION BLOCK DIAGRAM POWER SUPPLY 5
THANK YOU FOR USING THIS MIDAS PRODUCT To obtain maximum performance from this precision electronic product, please study these instructions carefully. Installation and operation of the XL88 are not complicated but the flexibility provided by its operating features merits familiarisation with its controls and connections. This unit has been prepared to comply with the power supply requirements that exist in your location.
After you have unpacked the unit Save all the packing materials - they will prove valuable should it become necessary to transport the unit. Please inspect this unit carefully for any sign of damage incurred during transportation. It has undergone stringent quality control inspection and tests prior to packing and left the factory in perfect condition. If, however, the unit shows any signs of damage, notify the transportation company without delay.
Introduction The Midas XL88 is a line level 8 x 8 matrix mixer which will greatly expand the capabilities of any mixing console to give eight fully independent sound balances from eight pre-mixed group outputs from the main console. A few specialised consoles have a matrix incorporated into their design, but the XL88 can offer this valuable extra facility to any sound installation, and is suitable for use with loudspeaker arrays, satellite links, land lines, and audio applications of all kinds.
Instrument Familiarisation Front panel functions Each of the eight channels of the Midas XL88 has the following features: 1) Direct Output Level Control. Regardless of the settings of any of the other controls on the unit, apart from the Direct Output Mute, this sets the gain of the Direct Output of the channel from minus infinity up to +10dB. The unity gain position (0dB) is marked. 2) Direct Output Mute. This cuts the Direct Output of the channel.
being measured by the meter is also available for pre-fade listen. 4) Matrix Output Mute. This cuts the Matrix Output from the module. A red LED indicates when Matrix Output Mute is in operation. 5) Matrix Output Fader. The Penny and Giles fader controls the level of the Matrix Output from the module. 6) Routing buttons. The eight Routing buttons send the input of the module to any or all of the eight Matrix Outputs. Routing is active when the button is depressed and the yellow LED is glowing.
Rear panel functions 3 4 2 6 1 5 7 1) Mains. Supplied via an IEC standard 3-pin connector. A compatible power cord is supplied with the unit. 2) Voltage Changeover Switch. The unit can be set for 220v or 110v operation. The switch is recessed behind a panel which indicates the voltage selected. Removal of this panel allows the switch position to be changed. The panel must then be turned around before it can be replaced and it will indicate the required mains voltage. 3) Mains Fuse.
Using the Midas XL88 Signal Paths There are four types of signal path through the XL88: 1) 2) 3) 4) Input to Direct Output Input to Matrix Output Input to Pre-Fade Listen Matrix Output to Pre-Fade Listen 1) Input to Direct Output. Using Module 1 of the XL88 as an example, the input to the module takes the following signal path: Input XLR 1 Direct Output Level Control Direct Output Mute Direct Output XLR 1 The Direct Output Level Control can vary the level from no signal to +10dB.
2) Input to Matrix Output. Using Module 1 of the XL88 as an example, the input to the module takes the following signal path: Input XLR 1 Routing buttons, Module 1 Routing Level Controls, Module 1 Matrix mixing point, any or all modules Matrix Output Faders, any or all modules Matrix Output Mutes, any or all modules Matrix Output XLRs, any or all modules The eight Routing buttons on the input module are used to select which outputs the signal will be routed to.
3) Input to Pre-Fade Listen.
To Pre-Fade Listen any output, leave the Meter Changeover switch on the corresponding module out, the LED will be off, and press the Output PFL button whose associated red LED will light. Any combination of inputs and outputs may be selected for PFL at the same time except that it is not possible to PFL the input and matrix output of any one module simultaneously. Using the Direct Outputs The Direct Outputs are simple to use.
Meter Changeover button out and pressing the corresponding Output PFL button. The signal will be taken from before the fader and muting switch and directed to the PFL output XLR. Using Pre-Fade Listen It is possible to pre-fade listen any combination of inputs and matrix outputs at the same time, except that it is not possible to PFL the input and output of any one module simultaneously.
The large output faders give quick, precise, control over the output level to each loudspeaker, or group of loudspeakers. To pre-fade listen any input or output, the XL88s PFL output is brought back to a spare channel on the main console where the operator can monitor it on headphones simply by pressing the appropriate PFL button on the main console.
Sophisticated Distribution Amplifier Another way of looking at the XL88 is as a sophisticated distribution amplifier. At its simplest, the XL88 can be a single-input eight-output distribution amplifier. Yet it can handle any level of complexity of distribution up to eight inputs combined in any proportion into eight individually controllable outputs. Stacking the XL88 The Direct Outputs of the XL88 can be used to link more XL88 units to create an 8 x 16 matrix with two XL88s, or an 8 x 24 matrix with three.
Audio connections Input The input circuitry is a transformerless, electronically balanced design which achieves a common mode rejection of at least -50dB from 20Hz to 10kHz. If transformer balancing of the inputs is required, this must be stated at the time of order as they are not retrofittable. Output The output circuitry is a transformerless, electronically balanced design which achieves an input rejection of at least -65dB from 20Hz to 10kHz. The output is capable of driving +21dBm into a 600 ohm load.
Specification Inputs Type Impedance (ohm) Balanced Unbalanced 20k 10k Outputs Direct Matrix P.F.L Type Min. load impedance Source impedance Max. level Eight Eight One Balanced (electronically) 600ohm <60ohm +21dBm Performance Frequency response (20Hz-20kHz) Distortion @ +20dBm Equivalent Input noise System noise 1 Input and 1 Output @ unity gain 8 Inputs and 1 Output @ unity gain Crosstalk Channel to Channel @ 1kHz Group to Group @ 1kHz Eight Balanced (electronically) +0.5dB <0.01% @ 1kHz 0.
Terminations Inputs Outputs Power 3 pin XLR 3 pin XLR 3 pin IEC Options Transformer input/output balancing 21
Circuit Description The Midas XL88 Matrix Mixer has been designed not only to provide the highest possible quality sound processing facilities, but also the greatest possible degree of reliability. However, no unit of such complexity can be expected never to need service, and to help anyone undertaking such work circuit descriptions will be found below.
Channel Module [Diagram XL88_1,2 & 4] Eight identical channel modules are fitted. These each consist of two pcbs interconnected by a 20 way IDC cable and a single screened channel assignment jumper. The lower (main) pcb carries all the input and output circuitry with the smaller top pcb holding the matrix mix controls and pfl routing. The channel input signal appears at XLR socket ST1 pin 3 [hot], 2 [cold] and 1 [gnd] on the main channel pcb (B2700).
The Zobel network R44/C48 is only fitted when a transformer is incorporated. ST7 allows the optional insert unit to be linked into the matrix output chain. When the insert option is not used a jumper is inserted linking pins 1&2. NOTE: Pin 1 of the input and output XLRs are connected together and to the other channels but not directly to the mixers 0 volt rail. Channel monitoring. Both audio and visual monitoring is provided for each channel.
The pfl select lines are distributed along the same ribbon cable as the mix lines and enter the module via ST2 pins 12 thro 19. These select lines are normally high [+15V]. They are brought to 0V to enable the channel pfl output. When enabled, the channel pfl output appears on the pfl mix buss via ST2 pin 10. Switch LED powering. The status LEDs are powered by the current source based around Q1. The order for the chain starting from Q1 is main mute, meter changeover & matrix mute on the main board.
PFL Mix & Output Module [Diagram XL88_3] The channel module pfl lines are individually selected by the eight push buttons with associated Led indicators that are located on this pcb [B2702]. The pushes keep the select lines high [+15V] in the off state and at 0V in the selected (on) state. The select lines are fed to the modules via the ribbon cable buss connected to ST1. The pfl audio mix buss enters the module via ST1 pin 10.
Earth lift. The input and output sockets have pin 1 (Gnd) common. This is not connected to the psu 0V as the latter is linked to mains earth. The XL88 is normally used with another console and the audio ground is established there. If however it is desired to use the XL88 as a stand alone unit, the grounds may be connected internally by fitting a link in the 0V LINK location by the side of ST1 on the Pfl mix & output module. A high value resistor may be found in this location to facilitate testing.
Power Supply The power supply provides the two power rails required for the successful operation of the XL88 matrix mixer. PLEASE NOTE THAT THE POWER SUPPLY CONTAINS CIRCUITRY WHICH GENERATES LETHAL VOLTAGES. ALL SERVICING OF THESE UNITS MUST BE REFERRED ONLY TO AUTHORISED SERVICE AGENTS OF KLARK TEKNIK plc. ON NO ACCOUNT MUST SERVICE WORK BE ATTEMPTED BY ANYONE ELSE.
Power Supply Assembly. [Diagram XL88_PSU] This contains the Mains transformer, fuses, voltage selection, rectifiers and linear regulators. Both negative and positive sections of the supply are identical with there own full wave rectifier, smoothing capacitor and 1.5A fixed voltage regulator. The regulators are mounted off the board on a common heatsink and connected to the pcb by short jumper leads. The output from the psu is linked to the Pfl, mix and output board by a jumper lead and plug.
Warranty This product is manufactured by Midas and warranted to be free from defects in components and factory workmanship under normal use and service for a period of one year from the date of purchase. During the warranty period, Midas will undertake to repair or at its option, replace this product at no charge to its owner when failing to perform as specified, provided the unit is returned shipping pre-paid, to the factory or authorised service facility.* No other warranty is expressed or implied.
COPYMASTER DO NOT REMOVE NOTE! This sheet is your Copymaster. Please duplicate on photocopier when needed. Service Request Form Please complete this form and send it to Klark-Teknik before returning the unit. Attach duplicate to the returned unit. NAME.............................................TELEPHONE..................................................... A D DRESS..................................................................................................................... .........................
Important Note It is often useful to call your dealer or the factory explaining the nature of the problem with the unit. In many instances the problem can be solved without returning the unit to the factory. If the unit has to be returned to the factory, use the original packing only. If you do not have the original packing, we will provide a replacement. Factory authorised service facilities are located throughout the world.
