In audio and acoustics, which device converts incident sound (pressure) waves into corresponding electrical signals suitable for amplification or recording?

Introduction:
Transducers convert energy from one form to another. In audio systems, capturing acoustic energy and turning it into an electrical signal is the first step for measurement, processing, transmission, or recording.

Given Data / Assumptions:

• We need a device that responds to sound pressure and produces an electrical output.
• Representative applications: live sound, studio recording, telephony, voice recognition.
• No requirement for amplification or radiation—only conversion from acoustic to electrical.

Concept / Approach:
A microphone is an electroacoustic transducer. Condenser (capacitor) mics vary capacitance with diaphragm movement, dynamic mics use electromagnetic induction with a moving coil, and piezoelectric mics use crystal-induced charge—each producing a corresponding voltage/current that mirrors the sound waveform.

Step-by-Step Solution:
1) Identify the input energy domain: acoustic (pressure waves in air).2) Identify the required output domain: electrical (voltage/current).3) Map candidate devices: only a microphone performs this acoustic-to-electrical conversion.4) Conclude that a microphone is the correct choice.

Verification / Alternative check:
Reverse device (loudspeaker) converts electrical energy to sound; the microphone is its conceptual counterpart, confirming roles in the signal chain.

Why Other Options Are Wrong:
Amplifier: increases signal amplitude; does not perform energy-domain conversion.

Antenna: converts electrical signals to electromagnetic radiation and vice versa, not sound.

Filter: shapes spectra; no energy-domain conversion.

Loudspeaker: converts electrical to acoustic (opposite direction).

Common Pitfalls:
Assuming an amplifier “creates” signal from sound. Without a transducer, the amplifier has nothing to amplify.

Final Answer:
a microphone