"What does 80 ohm vs 250 ohm mean for headphones?"

"Ohms (Ω) measure the headphone's electrical resistance. An 80Ω headphone is easier to drive — it gets louder from the same amount of power than a 250Ω headphone. A 250Ω headphone requires more voltage to reach the same volume and generally needs a dedicated headphone amplifier. When properly amplified, 250Ω headphones often sound slightly better than their 80Ω counterparts due to better driver control."

"Can I use 250 ohm headphones with a phone?"

"You can get audible volume from most modern phones with 250Ω headphones, but the sound quality will be compromised. The bass becomes loose and undercontrolled, the dynamic range compresses, and the phone's output stage works harder than it was designed to. 250Ω headphones should be paired with a dedicated headphone amplifier for best results."

"Is higher or lower impedance better?"

"Neither is universally better. Lower impedance (16–80Ω) headphones are more efficient and work well with phones and laptops. Higher impedance (150–600Ω) headphones are designed for use with dedicated amplifiers and often sound more controlled and dynamic when properly driven. The right choice depends on your source equipment."

What Is Headphone Impedance? A Plain-English Explanation

What headphone impedance actually means, why it matters for amplifiers and phones, and how to choose the right impedance for your setup.

What Impedance Means

Impedance (measured in ohms, Ω) is the total resistance a headphone presents to the electrical signal from your amplifier or device. It’s the combination of the DC resistance of the voice coil and the reactive impedance created by the driver’s inductance and compliance.

In practical terms: high impedance means the headphone is harder to push to volume, and the signal source needs more voltage to drive it.

The Basic Rule

Impedance	Typical Use	Requires
16–32Ω	IEMs, portable headphones	Phone, any source
38–80Ω	Portable cans, studio monitors	Phone or weak amp
150–250Ω	Professional monitors, reference headphones	Dedicated amp recommended
300–600Ω	High-end reference headphones	Dedicated amp required

Why Impedance Matters: Efficiency vs. Control

Low-impedance headphones (16–80Ω) get loud easily from weak sources. A phone producing 0.5V of output voltage drives them well. The downside: low-impedance headphones are more sensitive to output impedance from the source — if the amplifier’s output impedance is high relative to the headphone’s impedance, it can alter the frequency response.

High-impedance headphones (250–600Ω) require more voltage to reach the same volume level but are less affected by source output impedance. They tend to be used in professional contexts (studio consoles, mixing boards) because they were designed for professional equipment with adequate headphone outputs. At home, they require a dedicated amplifier.

The Output Impedance Problem

Output impedance is the resistance the amplifier presents to the headphone. The rule of thumb: the amplifier’s output impedance should be less than 1/8th of the headphone’s impedance (the “1/8 rule” or damping factor).

Example: A headphone with 32Ω impedance should be driven by an amplifier with <4Ω output impedance. Many cheap laptop jacks and phone output stages have 10–50Ω output impedance — above the safe threshold for low-impedance headphones. This can cause a measurable and audible change in frequency response.

Why this matters practically: If you plug a 32Ω headphone into a laptop with a 50Ω output impedance, the headphone’s bass response will roll off early because the source impedance is damping the driver’s movement. This sounds like less bass and less dynamic impact.

Real Examples

Sennheiser HD 600 (300Ω): Requires 100–300V p-p voltage swing for full dynamic range. A phone can produce about 1–2V. The result: audible volume but compressed dynamics, loose bass, and less of the HD 600’s characteristic precision. Pairing with a proper amplifier (Schiit Magni Heresy) transforms the HD 600.

Beyerdynamic DT 770 Pro (80Ω): Moderate efficiency. Gets to reasonable volumes from a phone. Bass can sound slightly loose from phone output vs a dedicated amp. The 250Ω version of the same headphone requires more voltage but rewards with tighter bass and better control when amplified.

Audio-Technica ATH-M50x (38Ω): Highly efficient. Drives easily from any source. Primarily benefits from amplification through noise floor reduction rather than power delivery.

Sensitivity: The Other Half of the Equation

Impedance and sensitivity work together. Sensitivity (dB/mW) tells you how loud a headphone gets from a fixed amount of power.

A headphone could be 300Ω but very sensitive (like some Beyerdynamic models at 96dB/mW), meaning it gets louder per milliwatt than a 32Ω headphone with 90dB/mW sensitivity.

Headphone	Impedance	Sensitivity	Drivability
Beyerdynamic DT 990 Pro	250Ω	96dB/mW	Moderate — amp recommended
Sennheiser HD 600	300Ω	97dB/mW	Moderate — amp recommended
HiFiMAN HE400SE	25Ω	91dB/mW	Harder — amp recommended
Audio-Technica ATH-M50x	38Ω	99dB/mW	Easy — phone adequate

The HE400SE is a planar magnetic: low impedance but also low sensitivity (91dB/mW). It needs more milliwatts of power to reach the same volume as a more sensitive headphone — an amplifier is still recommended.

The Practical Summary

Using a phone or laptop without an amp: Choose headphones with 80Ω or lower impedance. 250Ω+ headphones will be underpowered.
Have or plan to buy a dedicated amp: Either impedance works. 250Ω versions often sound slightly better when properly driven.
Using with a professional audio interface: Most interfaces provide adequate output for 250Ω headphones from their headphone jack.
Using IEMs (in-ear monitors): Low impedance (8–32Ω) and high sensitivity — be aware of noise floor from any amplifier; not all amps are quiet enough for IEMs.