CAT CAT Amplifiers and Loudspeakers 2

Question 1

What type of amplifier topology is most commonly used in modern high-power commercial audio amplifiers due to efficiency?

Accepted Answer

Class D (switching)

Answer

Class D switching amplifiers can achieve efficiencies above 90%, making them the dominant choice for high-power commercial applications where heat management and power draw are concerns.

Question 2

What is the significance of a loudspeaker's Thiele-Small parameter Fs?

Accepted Answer

The free-air resonant frequency of the driver

Answer

Fs is the free-air resonant frequency where the driver cone oscillates most easily; it is fundamental to enclosure design calculations.

Question 3

When bi-amping a speaker system, which driver typically receives the amplifier with higher power output?

Accepted Answer

The low-frequency (woofer) driver

Answer

Woofers require significantly more power to move air at low frequencies, so the high-power amplifier channel is assigned to the LF driver in an active bi-amp configuration.

Question 4

What does the term 'impedance dip' refer to in loudspeaker specification?

Accepted Answer

A frequency at which the speaker impedance drops below its nominal rated value

Answer

An impedance dip is a frequency region where the speaker's impedance falls below its nominal rating, potentially causing the driving amplifier to deliver more current than intended.

Question 5

What is the function of a limiter in a commercial amplifier or processor?

Accepted Answer

To prevent the amplifier output from exceeding a set ceiling to protect speakers

Answer

A limiter clamps the signal at a defined maximum level to prevent clipping and excessive power that could damage loudspeaker voice coils.

(CAT) Commercial Audio Technician Practice Test

(CAT) Commercial Audio Technician Practice Test

CAT CAT Amplifiers and Loudspeakers 2