--- title: "Dynamic Drivers: How the Standard Headphone Works" description: "How a dynamic driver moves air, why its impedance spikes at resonance, what it does better than planar and balanced armature designs, and where it struggles." url: "https://theaudiostuff.com/glossary/dynamic-driver/" type: "website" author: "Jakub Charkiewicz" --- > Markdown rendering of https://theaudiostuff.com/glossary/dynamic-driver/ > Canonical URL to cite: https://theaudiostuff.com/glossary/dynamic-driver/ > Generated from the published page. Text and links only; see the HTML for layout. Breadcrumb: [Home](https://theaudiostuff.com/) > [Glossary](https://theaudiostuff.com/glossary/) > Dynamic Driver # Dynamic Drivers: The Most Common Headphone Motor, Explained A dynamic driver is a voice coil in a magnetic gap, glued to a cone or dome. Current through the coil moves it, and the diaphragm follows. It is the oldest and most common transducer in audio because it is efficient, cheap to make well, and moves a lot of air for its size. ## Work it out for your gear [Headphone Power Calculator](https://theaudiostuff.com/tools/headphone-power-calculator/) How much amplifier power your headphones need to hit a target listening level. Sensitivity (dB/mW or dB/V), impedance, headroom: required mW, RMS volts, and peak voltage swing. ## How it works Three parts: a magnet assembly with a narrow gap, a coil of wire suspended in that gap, and a [diaphragm](https://theaudiostuff.com/glossary/#diaphragm) attached to the coil. Run an audio signal through the coil and it becomes an electromagnet whose field varies with the music. That field pushes against the permanent magnet, so the coil moves back and forth, and the diaphragm it is glued to moves with it. The diaphragm pushes [air](https://theaudiostuff.com/glossary/#air), and that is the sound. This is the same principle as a loudspeaker, scaled down. It is called dynamic because the motor is electrodynamic, and the design has survived a century of alternatives because it is genuinely good at the job. ## The resonance, and why it matters A mass on a spring has a natural frequency, and a [dynamic driver](https://theaudiostuff.com/glossary/#dynamic-driver) is exactly that: the moving mass of coil and diaphragm, suspended on a compliant surround. That resonance usually sits somewhere in the [bass](https://theaudiostuff.com/glossary/#bass), often between 40 and 100 Hz for headphones. Two consequences follow, and both show up in practice. **[Impedance](https://theaudiostuff.com/glossary/impedance/) spikes there.** At resonance the driver's motion generates a back-EMF that opposes the current, so impedance climbs, often to several times its nominal value. This is why a dynamic headphone's [frequency response](https://theaudiostuff.com/glossary/frequency-response/) changes with source [output impedance](https://theaudiostuff.com/glossary/#output-impedance): a high-output-impedance source forms a voltage divider, more voltage reaches the driver where impedance is highest, and you get a bass hump the headphone does not have on its own. [Planar magnetic](https://theaudiostuff.com/glossary/planar-magnetic/) drivers do not do this, because they have no such resonance. **Tuning has to account for it.** The resonance is not a fault, it is a design parameter, and much of what makes a dynamic headphone sound the way it does is how the designer damped and placed it. ## What dynamic drivers do well **[Efficiency](https://theaudiostuff.com/glossary/#efficiency).** Concentrating force on a small coil is an effective use of energy. Most dynamic headphones run acceptably from a phone, which is not true of most planars. **Bass [authority](https://theaudiostuff.com/glossary/#authority).** A dynamic driver excursion produces genuine air movement, and the result is impact you feel. It is why the technology remains dominant where visceral low end matters. **Cost and maturity.** A century of manufacturing refinement means a good dynamic driver can be built at a price no other topology matches. **Weight and size.** Small motor, light assembly, comfortable headphone. ## Where it struggles **Diaphragm break-up.** Force is applied at the coil, at the centre, and the rest of the diaphragm follows imperfectly. Above a certain frequency it stops moving as one piece and starts flexing in modes of its own, adding content that was not in the signal. Material science is largely aimed at pushing that point higher. **Source [sensitivity](https://theaudiostuff.com/glossary/sensitivity/).** The impedance peak means these headphones genuinely sound different on different sources, which is either a tuning opportunity or an inconsistency depending on your point of view. **[Resolution](https://theaudiostuff.com/glossary/#resolution) at the extreme.** At the top of the market, planar and [electrostatic](https://theaudiostuff.com/glossary/#electrostatic) designs generally retrieve fine detail more evenly, because they drive the whole diaphragm rather than one point. ## Variants worth knowing **[Beryllium](https://theaudiostuff.com/glossary/#beryllium), DLC, and coated diaphragms.** All attempts at the same goal: higher stiffness for lower mass, so break-up happens above the audible band. The benefits are real and incremental rather than transformative. **Dual and triple dynamic arrangements.** Multiple drivers splitting the band, common in in-ear designs. Trades [crossover](https://theaudiostuff.com/glossary/crossover/) complexity for reduced demand on each driver. **Hybrids.** A dynamic driver for bass paired with [balanced armatures](https://theaudiostuff.com/glossary/#balanced-armature) for the rest, which is an explicit acknowledgement that the dynamic driver's strength is the low end. ## Reviewed gear that shows this 15 reviews in the catalogue, highest-scoring 6 shown. Every score is anchored to the same published reference list. - [OLLO Audio X1 8.9/10 · $549](https://theaudiostuff.com/reviews/ollo-audio-x1/) - [HIFIMAN RE2000 PRO Silver 8.8/10 · $349](https://theaudiostuff.com/reviews/hifiman-re2000-pro-silver/) - [Meze 105 Silva 8.7/10 · $499](https://theaudiostuff.com/reviews/meze-105-silva/) - [Kiwi Ears Belle, Cadenza II, Orchestra II 8.1/10 · $30 to $350](https://theaudiostuff.com/reviews/kiwi-ears-belle-cadenza-orchestra/) - [Sivga Luan 8.1/10 · $299](https://theaudiostuff.com/reviews/sivga-luan/) - [Flare Audio E-PROTOTYPE 8.0/10 · $149](https://theaudiostuff.com/reviews/flare-audio-e-prototype/) ## Keep reading - [Full audio glossary](https://theaudiostuff.com/glossary/) - [How we test and score](https://theaudiostuff.com/about/#methodology-title)