CEA Signal Processing & Electronics Flashcards

What is the purpose of a 'noise gate' in audio signal processing?

Answer: To attenuate or silence a signal when it falls below a specified threshold

A noise gate closes (attenuates) the signal path when the input level drops below the threshold, effectively muting background noise during silent passages.

In audio electronics, what does 'capacitive coupling' (AC coupling) accomplish at a circuit input?

Answer: It blocks DC offset while allowing AC audio signals to pass

AC coupling uses a capacitor in series with the signal path to block any DC voltage while allowing the AC audio signal to pass through to the next stage.

What is the function of a sample-rate converter (SRC) in a digital audio workflow?

Answer: To convert audio from one sample rate to another without fully going back to analog

A sample-rate converter resamples digital audio data to change its sample rate, allowing devices or systems operating at different rates to work together.

What does a 'parametric equalizer' allow an engineer to control that a graphic EQ does not?

Answer: The center frequency, bandwidth (Q), and gain of each band independently

A parametric EQ gives the engineer independent control over the center frequency, the Q (bandwidth), and the gain for each band, enabling precise surgical adjustments.

What is 'intermodulation distortion' (IMD) in audio amplifiers?

Answer: New unwanted frequencies created when two or more signals interact nonlinearly in a device

IMD occurs when two or more signals pass through a nonlinear device and their interactions produce new sum and difference frequencies not present in the original signals.

In a transformer-balanced input, what is the primary role of the transformer?

Answer: To provide galvanic isolation and common-mode rejection between source and destination

The transformer magnetically couples the signal while providing complete electrical (galvanic) isolation, which eliminates ground loops and rejects common-mode noise.