CAT Problem Solving and Troubleshooting 3

Question 1

A passive loudspeaker measures 0 ohms across its terminals with an ohmmeter. This indicates:

Accepted Answer

A shorted voice coil or wiring

Answer

Zero ohms on a speaker terminal reading indicates a short circuit, most commonly a shorted voice coil or wiring fault.

Question 2

You plug a ¼-inch TRS balanced output into an unbalanced ¼-inch TS input and notice increased noise. The most appropriate fix is:

Accepted Answer

Use a direct box or balanced-to-unbalanced interface

Answer

A direct box or impedance-matching interface properly converts the balanced signal to unbalanced while rejecting common-mode noise.

Question 3

During sound check, the subwoofers produce output but the tops do not. Both are connected to a stereo amplifier. What should you verify first?

Accepted Answer

The amplifier's channel bridging switch or mode setting

Answer

A bridging or mono-sum switch on the amplifier can disable one channel's independent output, routing all power to the sub connected to it.

Question 4

A wireless microphone receiver shows full RF signal strength but the audio output is silent. The most likely cause is:

Accepted Answer

Mismatched RF frequency between transmitter and receiver

Answer

If RF is strong but audio is absent, the transmitter and receiver are likely tuned to different frequencies or channels.

Question 5

An in-ear monitor system produces a high-pitched whine only when the beltpack is within 3 feet of the transmitter antenna. This is caused by:

Accepted Answer

RF overload or desensitization at the beltpack receiver

Answer

Proximity-induced whine in IEM systems is typically RF overload (desense) caused by the beltpack receiver being too close to the transmitter's radiated field.

(CAT) Commercial Audio Technician Practice Test

(CAT) Commercial Audio Technician Practice Test

CAT Problem Solving and Troubleshooting 3