LA Audio Electronic SPX20 operation manual Description of Controls Inputs Section

4.0 DESCRIPTION OF CONTROLS

4.1INPUTS SECTION

INPUT 1

Left & Right sockets

These are insert points for Input 1. Plugging into these connectors breaks the signal from Input 1's rear panel XLRs. They are intended to allow a quick and easy way of temporarily connecting an external piece of equipment to the SPX20.

TRIM control

The TRIM control for Input 1 has a range of ±10dB which should provide adequate adjustment for levels provided by pro, semi-pro and commercial equipment. The centre position (12 o'clock) provides unity gain (0dB) and has a mechanical detent for easy positioning.

1button

Pressing this switch selects Input 1 as the signal source. It is fed to the TAPE RECORD output, on the rear panel, OUTPUT 1 & 2 and the Headphone amplifier.

The associated led lights to show Input 1 selected.

2, 3, 4, 5, 6 button

These select Inputs 2 through 6 as the Input source. Each select button has an associated led.

To select more than one input at the same time press and hold the first input and whilst holding this button press another button. It will be necessary to hold down all the inputs you want selected as each time a button is pressed it tries to cancel all other selections. Release all buttons.

TRIM control

Each input TRIM provides a gain range of -6dB (attenuation) at counter-clockwise (CCW) to +10dB clockwise (CW).

Setting up the SPX20

To ensure maximum headroom, noise and crosstalk performance it is important to have the correct signal levels within the SPX20. Please follow the following simple procedure.

When using equipment with a +4dBu output turn TRIM to almost CW and to fully CCW for -10dBV equipment as a starting point. Connect one of the outputs to your monitoring system and set LEVEL 1 or 2 control to give a suitable listening level. Then select each input in turn and adjust TRIM to give the same listening levels for each input. It should not be necessary to turn TRIM far from these settings.

Page 9