LA Audio EQ231G-SP - Manual (Page 9)

User Manual
2. Installation (contd.)
© LA Audio 2004
9
2.4. External connections
The input and output connectors are wired on female and male XLRs respectively,
wired as follows:
Pin 1: Ground
Pin 2: Hot balanced signal
Pin 3: Cold balanced signal
2.5. Impedance & Termination
Most modern audio systems have cable runs of less than 100 meters; the devices
used usually have very low output impedance and relatively high input impedance.
This allows equipment to be connected in series without regard to "impedance
matching" (as long as the succeeding input is greater than the stated minimum for the
output it is connected to).
LA Audio products conform to this standard; therefore inputs and outputs are usually
indifferent to varying load or source impedance. The only exception to this rule is
where the unit is connected to a transmission line or some older vacuum-tube
equipment, which require proper impedance matching. This may be achieved by
shunting the correct matching resistor across the inputs or outputs. The EQ231G-SP
has an input impedance of approximately 20k Ω and an output source impedance of
100 Ω , (20 Ω with the transformer option fitted). Its minimum following stage input
impedance should equal or exceed 600 Ω .