Introduction Thank you for purchasing the ISA 430 MKII brought to you by the Focusrite team ­ Ian, Trevor, Peter, Martin, Tom, Mick A'C, Phil, Chris G, Micky, Pauline, Melissa, Chris W, Rob J Snr, Simon J, Vernon, Giles, Rob J Jnr, Mick G, Tim, Dave, Paul and Simon. The chaps at Focusrite are a jolly hard working bunch and take a great deal of pride in designing, building and delivering products which are considered to be the best audio units around; we hope your new Focusrite unit lives up to that reputation and that you enjoy many years of productive recording. If you would like to tell us about your recording experiences, please email us at: sales@focusrite.com Important Safety Instructions Please read all of these instructions and save them for future reference. Follow all warnings and instructions marked on the unit. · · · · Do not obstruct air vents in the rear panel. Do not insert objects through any apertures. Do not use a damaged or frayed power cord. Unplug the unit before cleaning. Clean with a damp cloth only. Do not spill liquid on the unit. Unplug the unit and refer servicing to qualified service personnel under the following conditions: if the power cord or plug is damaged; if liquid has entered the unit; if the unit has been dropped or the case damaged; if the unit does not operate normally or exhibits a distinct change in performance. Adjust only those controls that are covered by the operating instructions. Do not defeat the safety purpose of the polarised or grounding type plug. A polarised plug has two blades with one wider than the other. A grounding type plug has two blades and a third grounding prong. The wider blade or the third prong are provided for your safety. When the plug provided does not fit into your outlet, consult an electrician for replacement of the obsolete outlet. WARNING: THIS UNIT MUST BE EARTHED BY THE POWER CORD. UNDER NO CIRCUMSTANCES SHOULD THE MAINS EARTH BE DISCONNECTED FROM THE MAINS LEAD. This unit is capable of operating over a range of mains voltages as marked on the rear panel. Ensure correct mains voltage setting and correct fuse before connecting mains supply. Do not change mains voltage settings while mains supply is connected. To avoid the risk of fire, replace the mains fuse only with the correct value fuse, as marked on the rear panel. The internal power supply unit contains no user serviceable parts. Refer all servicing to a qualified service engineer, through the appropriate Focusrite dealer. · The Focusrite Team Contents Introduction....................................................................................... 1 Contents............................................................................................. 1 Important Safety Instructions ........................................................ 1 Power Connections ......................................................................... 1 Rear Panel Connections.................................................................. 2 ISA 430 MKII Front Panel Controls ............................................. 3 Metering.............................................................................................. 3 Input Stage.......................................................................................... 4 EQ Module......................................................................................... 5 Compressor....................................................................................... 6 Gate ..................................................................................................... 8 De-Esser ............................................................................................. 9 Output ................................................................................................ 9 Inserts and Routing Matrix...........................................................10 Soft Limiter ......................................................................................13 Optional Analogue to Digital Converter (ADC) ....................13 Digital Output Front Panel Controls.........................................14 ADC Configurations......................................................................15 Mic Pre-amp Input Impedance.....................................................16 Applications......................................................................................17 FAQs .................................................................................................21 Specifications ...................................................................................24 Accuracy ...........................................................................................26 Copyright..........................................................................................26 Warranty ..........................................................................................26 Reset Sheet ......................................................................................27 Focusrite Distributors...................................................................28 Power Connections There is an IEC mains lead supplied with the unit which should have the correct moulded plug for your country. The wiring colour code used is: For units shipped to the USA, Canada, Taiwan and Japan: Live - Black Neutral - White Earth - Green For units shipped to any other country: Live - Brown Neutral - Blue Earth - Green and Yellow 1 Rear Panel Connections (Optional A/D Card shown fitted) XLR (Audio) Inputs and Outputs All 3-pin XLR audio connectors (main and post-mic outputs, mic, line & ADC inputs, insert sends & returns) are wired as follows: Pin 1 Screen/chassis Pin 2 Audio 0° Pin 3 Audio 180° INSERT SEND 2 This is used as the insert 2 output point, or as the analogue output from the dynamics module in `Dyn Split mode' (see `Dynamics Split' diagram on page 10). POST-MIC OUTPUT This is used as an output from the point immediately after the Phase section (i.e. before EQ and dynamics modules) allowing direct recording of mic, line or instrument inputs. It provides a direct-to-tape, ultra-short signal path output. Taking a signal from the POST-MIC OUTPUT does NOT interrupt a signal routed from the mic-pre to the EQ, dynamics etc., so a direct feed to tape can be achieved whilst simultaneously allowing processing of the same source. INST. HI Z INPUT 1/4" jack wired as follows: Tip Audio 0° Sleeve Screen/chassis KEY INPUTS 1/4" jack wired as follows: Tip Audio 0° Ring Audio 180° Sleeve Screen/chassis ADC INPUT 1 ADC Input 1 is used to route an external signal directly to the optional A/D card via the limiter. When selected using the ADC Input 1 button on the front panel, ADC Input 1 replaces the internal processed signal being fed to the left side of the A/D card (i.e. whatever is connected to the mic, line or instrument input no longer routes to the ADC). For further detail see ADC Input 1 & 2 on page 13. It also allows a signal to be summed with the processed signal from the unit by pressing the Ext Sum switch and using the Ext Level controls. This signal can be routed to the A/D card and main output (See ADC Input 1 & 2 on page 13.) DYNAMIC LINK 1/4" jack wired as follows: Tip Compressor sidechain link Ring Gate sidechain link Sleeve Screen/chassis MIC/LINE/INST INPUT Any one of these inputs may be used as the main input to the ISA 430 MKII's main input. Signals routed to these inputs are referred to as the `Internal' or `Int' signal path. ADC INPUT 2 ADC Input 2 is also used to route an external signal directly to the optional A/D card via the limiter. When selected using the ADC Input 2 button on the front panel, ADC Input 2 replaces the internal unprocessed signal being fed to the right side of the A/D card (i.e. whatever is connected to the mic, line or instrument input). This still allows the processed signal (i.e. whatever is connected to the mic, line or instrument input) to route to the left side of the A/D card. Hence there are four possible setups for the ADC 1 & 2 input switches. (See ADC Input 1 & 2 on page 13.) INSERT RETURN 1 This is used as the insert 1 input point, or as the input to the EQ modules in `EQ Split mode' (see `EQ Split' diagram on page 10). INSERT SEND 1 This is used as the insert 1 output point, or as the analogue output from the EQ module in `EQ Split mode' (see `EQ Split' diagram on page 10). INSERT RETURN 2 This is used as the insert 2 input point, or as the input to the dynamics modules in `Dyn Split mode' (see `Dynamics Split' diagram on page 10). MAIN OUTPUT This output is used as the main analogue internal signal output, and is fed by whatever is connected to the MIC INPUT, LINE INPUT or INST INPUT, after this signal has been routed through the processing modules. 2 DYNAMIC LINK You can connect two ISA 430 MKII units (using a standard TRS 1/4" jack-to-jack lead between the DYNAMIC LINK sockets) to allow both the compressor and gate sections to behave as stereo pairs of processors. When connected in this way, the compressors and gates behave as single stereo devices. Both units respond to the higher of the two input signal path levels. (The EQ channels can be matched visually or aurally to be used as a stereo pair if required.) Hence, to drive the compressors and gates as stereo pairs, set the threshold pot of one of the compressors and one of the gates to maximum (fully clockwise). The second unit will then act as `master', allowing one set of parameter changes to affect both compressors or gates identically. NB: The deessers are not linked. Retrofitting the Optional A/D Card The optional A/D card can be retrofitted to a standard ISA 430 MKII at any time. Full fitting instructions for this option are included with the Card. ISA 430 MKII Front Panel Controls Power Applies power to the unit. Turn on the ISA 430 MKII before powering up devices to which the outputs are connected. VU meter when the Listen switches are pressed in the compresser, gate or de-esser sections. The Listen LED will also light when any of these switches are selected. Inst Input Unbalanced instrument sources may either be connected via the rear panel INST. HI Z INPUT, or via this duplicated front panel jack. If both are connected, the front connection overrides the rear connection. No DI box is required. Meter 0VU Calibration The metering calibration for the input level and insert return levels can be shown over two different ranges: · · 0VU corresponds to +4dBu. 0VU corresponds to +18dBu. Metering Either can be selected via the Meter 0VU Calibration button. For the compressor, the meter indicates the amount of gain reduction applied, from 0VU (no compression) to -20VU (corresponding to 20dB of gain reduction). NB: The effect upon `Listen' of calibration is similar to that on input and insert returns. However, as the signal being monitored by the listen circuit is a sidechain source, the meter acts more as a visual indication of the attack and decay of a signal, rather than true level. Listen LED This illuminates when Listen is selected on the compressor, expander/gate or de-esser, and indicates that the unit is monitoring the selected sidechain frequencies. N.B. When attempting to listen to the dynamics in `Split Dynamics' mode, pressing the Listen switch will only result in visual monitoring; as the dynamics are split from the monitoring path, they can be viewed in the meter but not heard. Meter Source The VU meter can display input level, Insert 1 return level, Insert 2 return level, compressor gain reduction or sidechain Listen level. Press the Meter Source button to step through Input, Insert Rtn 1, Insert Rtn 2 and Comp sources as indicated by the corresponding LEDs. The sidechain Listen level will automatically be displayed on the Audio O/L LED This LED illuminates when the peak signal level reaches or exceeds +20dBu, or when the peak signal level reaches 6dB below the clip point. The signal is monitored at five points: post-the input gain Trim, post-Insert 1, post-the EQ 3 3 module, post-Insert 2, and post-the Dynamics module (since each module could cause clipping if incorrectly set up). Occasional short-duration peaks which may cause the LED to blink will not normally cause audible distortion, but if the LED is lit constantly, the level in the appropriate module should be reduced to prevent overloading. legend). The gain range is split between two gain modes depending upon the status of the 30-60 switch: Mode 1: Mic Gain Range 0-30 With the 30-60 switch off, the rotary gain knob operates over a gain range of 0dB to +30dB, the level of gain chosen being indicated on the front panel by the outer arc of yellow numbers around the gain knob. Mode 2: Mic Gain Range 30-60 With the 30-60 switch on (illuminated), the rotary gain knob operates over a gain range of 30dB to 60dB, the level of gain chosen being indicated on the front panel by t ...