29.01.2009 Neue Produktinformationen von NTI

Reliable XLR Pin 1 Cable Testing with MR-PRO

NTI introduces a unique feature of the Minirator MR-PRO: The "Pin 1 Cable Tester" functionality. It detects the proper connection from the cable shield or 3rd conductor wire to the XLR connector pin 1. The Minirator impedance test function measures minor capacitive differences between the two wires and the shielding of an XLR audio cable, thus senses false pin 1 connections accurately.

Audio cables are frequently soldered incorrectly to the XLR connector, e.g. the cable shield or 3rd conductor is unconnected at one end, or connected to pin 3 at both cable ends instead to the assigned pin 1. Cables with shields/wires connected to pin 3 (or pin 2) are commonly analyzed as “OK” by conventional cable testers basing on the typical 1:1 connection test, but actually cause unbalance and the audio quality worsens passing through such bad cables.

How can an incorrectly connected shield be detected?

The NTI MR-PRO detects the correct connection from the cable shield to pin 1. The MR-PRO accurately analyzes a connected audio cable for all the individual impedances between the three connector pins 1, 2 and 3. A properly wired XLR cable is a nearly perfect balanced device. An audio cable with incorrect shield connections results in an unbalanced capacitive load at pin 2 and pin 3 in relation to pin 1, resulting in different impedance readings at pin 2 compared to pin 3. The Minirator precisely measures this capacitive difference of the connected audio cable, indicating an incorrect shielding connection on the MR-PRO display.

Foto: The detailed impedance view shows an asymmetric load, indicating a wrong connected Pin 1

Download Application Note here.