Meyer Sound CQ-2 operating instructions Audio Input, Safety Issues, Troubleshooting

Safety Issues

Pay close attention to these important electrical and safety issues.

Use a power cord adapter to drive the CQ from a standard 3-prong outlet (NEMA 5-15R; 125 V max).

Audio Input

The CQ presents a 10 kΩ input impedance to a three-pin XLR connector wired with the following convention:

Pin 1 — 220 kΩ to chassis and earth ground (ESD clamped)

Pin 2 — Signal

Differential Inputs

Pin 3 — Signal

Case — Earth (AC) ground and chassis

earth ground

chassis ground

The CQ requires a grounded outlet. Always use a grounding adapter when connecting to ungrounded outlets.

Pins 2 and 3 carry the input as a differential signal; their polarity can be reversed with the input polarity switch on the user panel. If the switch is in the up position, pin 2 is hot relative to pin 3, resulting in a positive pressure wave when a positive signal is applied to pin 2. Use standard audio cables with XLR connectors for balanced signal sources.

Shorting an input connector pin to the case can form a ground loop and cause hum.

Do not use a ground-lifting adapter or cut the AC cable ground pin.

A single source can drive multiple CQs with a paralleled input loop, creating an unbuffered hardwired loop connection. Make certain that the source equipment can drive the total load impedance presented by the paralleled input circuit. For example, since the input impedance of a single CQ is 10 kΩ, cascading 20 CQs produces a balanced input impedance of 500 Ω. If a 150 Ω source is used, the 500 Ω load results in a 2.28 dB loss.

Keep all liquids away from the CQ to avoid hazards from electrical shock.

Do not operate the unit if the power cables are frayed or broken.

Tie-wrap anchors on the amplifier chassis provide strain relief for the power and signal cables. Insert the plastic tie-wraps through the anchors and wrap them around the cables.

Troubleshooting

If the Active lamp does not light after connection to an AC source for three seconds, the problem is probably in the power supply. In the unlikely case that the circuit breakers trip (the white center buttons pop out), the amplifier or power supply may be malfunctioning. Do not reset the breakers! Contact Meyer Sound for repair information.

If abnormal noise (hum, hiss, popping) is produced from the loudspeaker, disconnect the audio source from the speaker. If the noise stops, then the problem is not within the loudspeaker; check your audio and AC power sources.

If problems persist, contact Meyer Sound. If repairs are necessary, the CQ’s modular components are easy to remove and ship.

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