Gear & technology
Amplifier
Also called amp, headphone amp, power amp, integrated amp
An amplifier takes a small audio signal from a source or DAC and makes it strong enough to drive headphones or speakers. Headphone amps deliver milliwatts into loads of roughly 16 to 600 ohms; power amps deliver tens or hundreds of watts into speakers.
Whether you need a separate amplifier depends on the load. A phone drives most IEMs and 32 Ω headphones; a 300 Ω headphone or an insensitive planar wants more voltage or current than a phone provides, which is what a desktop amp supplies. See Impedance and Sensitivity for how to judge it.
Speaker amplifiers come as integrated amps, which include volume control and input switching, or as separate Preamp and power amp boxes. A Receiver bundles an amplifier with a radio tuner or surround processing.
Designs divide into Solid-state and tube, and by output stage into Class A, Class AB and Class D. Specifications to read are Power output into your load, Output impedance and THD+N.
Where you’ll see this on tonistry.
- Browse every product in the Amplifiers category.