Contents Section 1 : Contents Section 2 : Introduction 2.1 The GX 230 Section 3 : Performance Highlights Section 4 : Installation 4.1 Unpakking the unit 4.2 Checking the mains voltage 4.3 Setting the mains voltage 4.4 Replacing the mains fuse 5.5 The rear pannel...
Introduction The GX 230 The APEX GX230 is a dual channel 30 band 1/3 octave graphic equaliser, incorporating our newly developed DLT hybrid circuits. A high-pass filter precedes the equaliser in each channel and is switchable in and out of the signal path. The unit is built to the highest professional standards both for electronics and mechanics.
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components on the hybrid circuits yet has another important advantage : because of the largely reduced number of soldered connections, reliability is boosted to an extent only exceeded by integrated circuits (some call it “fit and forget technology”). The controls of the graphic equalisers provide up to 12 dB of reciprocal cut and boost at the 30 distinct centre frequencies.
Installation In addition to these operating instructions and the GX 230 equaliser, the packaging also contains : • A power cord (see note for U.K.). NOTE This apparatus must be earthed. The wires of the mains lead are coloured in accordance with the...
Checking • Check if the voltage selector on the rear of the equaliser indicates the correct supply voltage before connecting the the mains voltage equaliser to the mains. Setting • Remove the plug from the wall socket and check if the mains fuse is of the correct rating.
The rear panel 1 MAINS FUSE Holds the mains fuse. 2 MAINS SOCKET • Insert the plug of the mains lead into the mains socket. The mains connector is a standard 3 pin IEC connector. The centre terminal of the connector is directly connected to the chassis of the equaliser.
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4 SERIAL NUMBER This number is the fingerprint of the unit and should be quoted in any correspondence concerning the unit. 5 SIGNAL GROUND LIFT This switch disconnects the signal ground from the mains and chassis earth. The switch should be used if hum due to ground loops is experienced and will generally solve the problem.
The GX 230 is designed for standard 19” rack mounting as well as Rack mounting free standing outside a rack cabinet. The unit requires three standard rack units. Mounting the unit directly over large heat-producing devices may shorten component life and therefore, is not recommended.
Signal connections For maximum performance, the use of two-conductor shielded cable is recommend. Because the shield does not carry signal, interference between signal current and shield current is minimised in this way. Ordinarily the shield is connected to ground at one end Input The inputs of the equaliser are electronically balanced.
Some general rules for input connections : • Although not necessary, because of input circuit symmetry, it is best to always use the “+” and “-” input terminals when wiring the equaliser. In this way, hum pick-up from the open terminal is avoided.
Grounding Because it is not always possible to determine whether the equipment connected to the equaliser have their circuit ground connected to earth and because the mains earth is not always of good quality, it is hardly possible to give general rules for •...
The Equaliser When pressing the power button, AC mains is applied to the POWER unit. The red led below the power switch illuminates as you switch on the apparatus. The fail safe relays will open, switching the filters between the input and the output of the unit. When switching power off, the fail safe relays will link the input of each The O/LOAD indicator illuminates when the peak signal voltage O/LOAD...
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The sliders of the graphic equaliser allow centre gain adjustment for each of the indicated centre frequencies. NOTE Note :The rotary controls of the GX 230 are high quality conductive plastic potentiometers. However, calibration accuracy of these controls is only modest.
General operating instructions Introduction If you are not familiar with equalisers, the best thing to do before first turn-on is to put all controls in their central position. When the unit is not powered or the power supply fails, the fail-safe relay of the equaliser links input and output.
HP filter The HP filter has a turnover frequency of 30Hz. The filter has a roll-off slope of 18dB/octave and is of the Butterworth type for maximally flat response. It is particularly useful in situations where potentially harmful subsonic signals are likely to cause speaker or amplifier overload.
Specifications INPUT: • Electronically balanced • Absolute overload point : +22dBu • Impedance: 10 Kž (each leg) equal impedance for “+” and “-” legs • CMRR better than 65dB (20Hz-20KHz) • XLR-3 type connector connections : 1 signal ground; 2 hot (+); 3 cold (-) OUTPUT: •...
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any point in the equaliser comes within 2dB of clipping FILTERS: • 30 ISO centre frequencies: 25Hz-20KHz 1/3 octave • Centre frequency tolerance: ±1% (typically better than ±0.5%) • Q tolerance: ±1% • Max boost/cut: 6 or 12dB ±0.5dB reciprocal •...
Maintenance and service information Preventive Preventive maintenance consists of cleaning and visual inspecting the unit. When accomplished regularly, preventive maintenance maintenance may prevent malfunction and lengthen the apparatus life. The severity of the environment in which the equaliser is used determines the required frequency of preventive maintenance.
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SERVICE REQUEST FORM Please copy and complete this form as completely as possible and return it to Apex or an authorised Apex service centre together with the defective unit. Name/Company:............................Adress:................................................... Telephone:........Country:..............Model No:......... Serial No:.............. Purchased from:....... Date:..............•...
WARRANTY Summary We, APEX nv Bosdel 52 3600 GENK Belgium warrant to you, the original purchaser and any subsequent owner of this Apex product, for a period of one year from the date of purchase by the original purchaser that the product is free of defects in components and factory workmanship under normal use and service.
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from us. Corrective action will be taken within a reasonable time of the date of receipt of the defective product by us or the service centre. If the repairs made by Apex or the authorised service centre are not satisfactory, notify Apex or the service centre immediately. Repairs Product changes We reserve the right to change the design on any product without prior notice and with no obligation to make corresponding changes...
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