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ISA One Controls and Features

Updated

Front Panel

ISA_One_Front_Panel_Annotated.png

  1. 10 dB stepped Mic & Line Gain switch. Mic: 0-30 / 30-60 dB | Line: -20 +10 dB

  2. Selects the high mic input range (30-60 dB) on the Gain switch

  3. Trim pot: 0 +20 dB for the Mic & Line inputs

  4. Applies +48V phantom power to the mic input XLR

  5. Inverts polarity (Phase) of the selected input

  6. Applies the high-pass filter (HPF) to the selected input

  7. Switches the Insert return signal into the channel path

  8. Input source selection switch

  9. Z In (Input) selects the input impedance for the Mic input

  10. Z In (Instrument) selects the input impedance for the Instrument input

  11. Gain pot for the Instrument input

  12. 1/4” mono Jacks for the Instrument input (DI) with a parallel output to an Amp/combo.

  13. Enables the VU meter calibration mode

  14. Moving-coil VU meter

  15. Peak-reading LED bar graph Input meter

  16. Toggles meters 14 & 15 to indicate the signal at Pre or Post the Insert point

  17. Peak-reading LED meter indicates the instrument input (DI) or the EXT IP (when connected)

  18. A-D option card clock and sync selection.

  19. 1/4” stereo Jack socket for Headphones

  20. Headphone volume pot

  21. Sends the stereo Cue Mix inputs (on the rear panel) to the headphones

Metering

ISA One’s front panel provides three level meters: a traditional moving-coil VU meter – which shows the average volume level, plus two peak-reading LED bar graphs – which indicate dBFS, ie., the level in dB, relative to maximum output (when the red ‘0’ LED illuminates).

ISA_One_Metering_Front_Panel.png

The VU meter and the left Input LED bar graph are linked and both indicate the main signal (the selected Input, post-Gain & Filter) at the point set by the status of the Post Insert switch:

  • Post Insert Switch Off – The VU and Input LEDs indicate the signal level at the Insert Send connector. This will also be the Main O/P when the Insert switch is off.

  • Post Insert Switch On – The VU and Input LEDs now indicate the signal level at the Insert Return connector. This will also be the Main O/P when the Insert switch is on.

The right DI/Ext bar graph indicates the level at one of two different signal locations, determined by the presence of a jack at the rear Ext I/P socket:

  • Ext I/P unused – The right LED meter indicates the level at the DI O/P connector.

  • Ext I/P jack inserted – The right LED meter now indicates the level at the external input.

Metering the A-D Inputs

The two inputs to the A-D option card are fed from; Ch.1: the Main O/P; Ch.2: the Ext I/P.

With the Ext I/P jack connected – and the left LED meter indicating the Main O/P (see above) – the LED bar graphs will display both signals being sent to the A-D card inputs.

At default calibration, LED ‘0’ indicates a signal level of 22 dBu, which is the maximum input level of the A-D card.

Meter Calibration

The calibration of the VU and LED meters can be adjusted using trim controls on the rear panel. Note that changes to the VU meter calibration will only take effect by pressing the VU Cal switch.

  • VU Meter – The default VU meter lineup (VU Cal switch off) is 0 VU = 4 dBu.

    With the VU Cal switch on, rotating the VU Meter Cal knob will set the value between 0 VU = 11 dBu (fully anti-clockwise) and 0 VU = 26 dBu (fully clockwise), with 0 VU = 22 dBu at the centre detent position.

    VU_Meter_CAL_Drawing.png

  • LED Meters – The default setting of 0 dBFS = 22 dBu occurs when the knob is in its central detent position – to correspond with the maximum input level of the A-D card.

    Rotating the Peak Meter Cal knob will set the value between 0 dBFS = 15 dBu (fully anti-clockwise) and 0 dBFS = 26 dBu (fully clockwise).

    Peak_Meter_CAL_Drawing.png

Rear Panel

ISA_One_Rear_Panel_Annotated.png

  1. Mains power switch.

  2. Standard IEC receptacle for AC mains. ISA One features a ‘Universal’ PSU, enabling it to operate on any supply voltage between 100 and 240 V AC

  3. Slot for ISA ADN2 analogue to digital conversion card. The card allows two audio signals from the ISA One to be added to a Dante network. It also provides AES3, S/PDIF and ADAT signals. See the following page for A-D card details

  4. Adjusts the VU meter ‘0’ indication between 11 and 26 dBu. At the detent position, the reading will be 22 dBu – which matches the maximum input level of the A-D card.

    The Cal control only takes effect when the front panel “VU Cal” button is pressed. When not pressed, VU ‘0’ indicates a level of 4 dBu.

  5. Adjusts the LED meters' reading at full scale between 15 and 26 dBu. At the detented position the reading will be 22 dBu

  6. Balanced 1/4” TRS Jack sockets for the Left and Right Cue Mix inputs

  7. Balanced 1/4” TRS Jack socket (Ext I/P) which feeds input 2 of the A-D option card

  8. Balanced 1/4” TRS Jack sockets for Insert Send and Return. The insert can be added to the channel path by pressing the front panel Insert switch

  9. XLR-3 male provides a Line-level output of the instrument signal (DI). The signal is post the instrument gain control and is always available irrespective of any switch selection

  10. XLR-3 male for the Main channel output – as selected by the front panel Input button. This output is linked internally to input 1 of the A-D option card

  11. Balanced 1/4” TRS jack for the Line input. The two line input connectors are internally linked so must not be connected to different sources

  12. XLR-3 female connector for the Line input. The two line input connectors are internally linked so must not be connected to different sources

  13. Balanced XLR-3 female connector for microphone input. Phantom power can be applied by pressing the +48V switch

A-D Option Card

The optional ISA ADN2 A-D card can be retrofitted to an ISA One at any time. Engineering experience is not required as the card can easily be installed by the user.

Note

The ISA One does not support the earlier ISA 2-Channel A-D card.

Once fitted, the configuration of the card is carried out over the network using either RedNet Control or the Dante Controller software application.

The fitting instructions and network software applications are included with the A-D card option.

A line drawing of the ISA ADN2 digital card's front panel. Left to right: Wordclock In, Wordclock out, Dante Primary & Secondary, ADAT TOSlink Output, S/PDIF RCA Output, AES3 XLR output.

Word Clock – Input

Allows the card to be synchronised to an external Word Clock source via the BNC connector.

Word Clock – Output

Provides an output of the external Word Clock source connected at the “Word Clock In” BNC connector or, transmits the internal sample frequency of the A-D card.

  • When the ISA One is following other units within a larger digital system, the Word Clock Out connector can be used to pass on the Word Clock signal to the next device.

  • When the unit is not following another device and is in Internal Clock mode, the Word Clock Out connector outputs the sample frequency selected on the ISA One front panel.

Primary Network Port

Latching RJ45 connector for the Dante network. Use standard Cat 5e or Cat 6 network cable to connect the ISA ADN2 to a local Ethernet switch which is connected to the Dante network. Adjacent to the network sockets are LEDs which illuminate to indicate a valid network connection and network activity.

Secondary Network Port

Can be used as the Secondary Dante network connection where two independent Ethernet links are being used (Redundant mode), or as an additional port on an integral network switch on the primary network (Switched mode).

ADAT

2-channel ADAT optical output using standard TOSLINK connector.

S/PDIF I/O

A 2-channel digital interface on RCA (phono) connector.

AES3 Output

2-channel AES3 output on XLR-3 male connector.

Tip

See Connector Pinouts for pinout information.

See Pro Tools Interfacing for Pro Tools information.

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