Bone conduction vs air conduction headphones: the two paths to your inner ear, compared

The definition

Your inner ear, the cochlea, converts vibration into nerve signals. There are two ways to vibrate it. Through the air: sound waves enter the canal, move the eardrum, and three small bones pass that motion to the cochlea. Through the skull: a transducer pressed to the bone in front of the ear vibrates the bone itself, and the cochlea, which is embedded in that bone, moves with it. Shokz describes its version as vibrations “transmitted through the skin and temporal bone to the cochlea, bypassing traditional air conduction transmitters like the external auditory canal or eardrum.”

You already use both. Your own voice reaches you partly through bone, which is why recordings of yourself sound wrong: the bone-conducted part is missing.

Side by side

Air conduction: sealed and open

A sealed earbud has a tiny driver working against a closed pocket of air in the canal, which is how something so small makes bass. Remove the seal and the same driver is pushing into open space; makers respond with larger drivers (the Soundcore AeroFit 2's 20 x 11.5 mm, the Cleer ARC 5's 16.2 mm), dual drivers (Shokz DualBoost) and aiming (DirectPitch). Open-ear air conduction sounds fuller than bone conduction and thinner than sealed. It leaks, because the speaker is pointed at open air. See open-ear vs in-ear for that side of the family.

Bone conduction: what vibration can and can't do

Bone is stiff and heavy compared to air. It transmits mid and high frequencies well enough for voice and most music, and low frequencies badly: producing bass would mean vibrating your skull with enough energy to feel. SoundGuys' verdict on the category: bone conduction headphones “don't sound as good as a pair of the best headphones on the market will” because “sub-bass and bass are virtually inaudible.” What you get back is a canal that is entirely unobstructed, a fit held by your skull, and a sealed device with no hinge or case, which is why the highest water ratings and the only swim headphones on this site are bone conduction. The neckband ranking is at best bone conduction headphones.

The hybrid: DualPitch

What it means for hearing

Nothing, in terms of risk: both paths end at the same hair cells. NIDCD: “Long or repeated exposure to sounds at or above 85 dBA can cause hearing loss,” and that applies whichever way the energy arrives. The full discussion, with sources, is in are bone conduction headphones safe. Where the path does matter is medical: bone conduction bypasses the outer and middle ear, which is why it has a long history in hearing aids for people with conductive hearing loss. That's a conversation for an audiologist, not a spec sheet.

Picks

The mechanism, step by step

If the transducer-and-skull half of this comparison is the part you came for, it has a page of its own: how do bone conduction headphones work?