Ohms
Definición
The unit of measurement for electrical impedance. Ohms (Ω) quantify the opposition a circuit presents to alternating current. When someone says "a microphone has 48 ohms" or "an interface has 10k ohms," they are measuring impedance — how much opposition to signal flow exists in that device. Ohms and impedance are not separate concepts; ohms is simply the unit used to express impedance values.
En palabras simples
The unit that measures impedance. A microphone outputs around 48–600 ohms. A professional interface accepts 10,000+ ohms. A cheap portable has 1,000–2,000 ohms. The higher the ohms in the input (the device you're plugging into), the better it couples with your microphone. Low ohms = weak, thin signal.
En la práctica
A 250-ohm dynamic microphone plugged into a 10,000-ohm (10k) professional interface produces full, clear signal. The same microphone into a 1,500-ohm portable recorder sounds quiet and dull — the low ohm input is not high enough to properly couple with the microphone's 250-ohm output.
Confusión común
"Ohms" and "impedance" are the same thing — ohms is just the unit. It's like asking "what's the difference between meters and length?" They're not different; meters is how you measure length. Similarly, ohms is how you measure impedance. If someone says "the impedance is 48 ohms," they mean the opposition to current flow is expressed in units of ohms.
Fuentes y verificación
- Self, D. — Small Signal Audio Design (3rd ed., impedance chapter)Focal Press, 2020
- AES48-2005 — AES standard on interconnections — Grounding and EMC practicesAudio Engineering Society
Última verificación: 2026-08-05