User manual MIDAS CONSOLES MIDAS XL88

[. . . ] 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 2 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 Matrix Mixer Product Name 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: . . . . . . . . . . . . . . . . . . . Alex Cooper Authority: Project leader Date: 28th November, 1995 Attention!The attention of the specifier, purchaser, installer or user is drawn to special limitations of use which must be observed when these products are taken into service to maintain compliance with the above directives. Details of these special measures and limitations to use are available on request and are also contained in product manuals. 3 ATTENTION! [. . . ] Output The output circuitry is a transformerless, electronically balanced design which achieves an input rejection of at least -65dB from 20Hz to 10kHz. If transformer balancing of the outputs is required, this must be stated at the time of order as they are not retrofittable. Balanced Circuits Transformer or electronically balanced connections have the benefit of Common Mode Rejection which eliminates externally induced interference such as mains hum etc. Balancing is especially useful when long cable runs are used between pieces of equipment. Transformer balanced circuits have the added advantage of being fully floating with the ground (earth) or screen being totally isolated from the signal. In installations where a difference in earth potential is likely to occur, this isolation prevents grounding problems which can in some cases damage the equipment. XLR Pin Connection (Input and Output) Pin 1 Ground (Earth) Pin 2 Signal Pin 3 Signal Unbalanced For unbalanced operation, connect Pin 2 to Pin 1 only on the inputs/outputs which are being run unbalanced. 19 Specification Inputs Type Impedance (ohm) Balanced Unbalanced Outputs Direct Matrix P. F. L Type Min. level 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 Power Requirements Voltage Consumption Weight Nett Shipping Dimensions Width Depth Height Eight Balanced (electronically) 20k 10k Eight Eight One Balanced (electronically) 600ohm <60ohm +21dBm +0. 5dB <0. 01% @ 1kHz 0. 03% 20Hz-20kHz <-94dB 22Hz-22kHz unweighted <-92dB 22Hz-22kHz unweighted <-88dB 22Hz-22kHz unweighted -100dBu -90dBu 110/120/220/240V 50/60Hz <45VA 8kg 10. 5kg 482mm (19 inch) 205mm (8 inch) 176mm (7 inch) 20 Terminations Inputs Outputs Power Options 3 pin XLR 3 pin XLR 3 pin IEC 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. The less experienced technician or operator may find the following notes useful in an emergency fault finding when more experienced help may not be available. The priority in fault finding is to adopt a logical approach, as this is the quickest way to identify the precise source of a problem. For instance, if an input module appears to have failed, it will be helpful to establish with greater accuracy where the failure is. Does the direct output function even though the matrix output does not?In this way a particular circuit block can be identified as faulty, and a careful inspection will often reveal a disconnected wire, a damaged component, or a suspect IC that can be changed. Furthermore, if help is sought over the telephone, it will be helpful to have the greatest possible amount of detail for the technician to work with. When performing tests on the console, it is tempting to unplug modules without switching off the power supply THIS MUST NEVER BE DONE, AS IT NOT ONLY DESTROYS SOME COMPONENTS AT ONCE, BUT LEADS TO THE EARLY FAILURE OF MANY THAT APPEAR TO HAVE SURVIVED. The power supply is designed to bring the console to full power gradually, which protects sensitive components from damage caused by voltage spikes created by sudden powering up. 22 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). If no input transformer is fitted, links L1 & L2 are used to bypass the transformer option and the transformers Zobel network components, R9, R10 & C8 are omitted. filtering is provided by R1/C3 and R6/C6, and over-voltage protection by D1/D2 and D3/D4. [. . . ] [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. 29 30 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. [. . . ]