Wired audio glossary

Inline mic

An inline mic is the microphone built into the cable of a wired earphone, usually positioned between your chin and collarbone so it can pick up your voice clearly on calls.

The microphone built into the cable of a wired earphone, not into the earbud housing. The inline mic sits on the cable itself, usually positioned between your chin and collarbone when worn. That placement matters because it puts the mic close to your mouth, which is where it needs to be to pick up your voice clearly on a call.

The alternative is a mic built into the earbud housing, which sits at your ear. A mic at ear level is picking up a lot of room before it gets to your voice. A mic at chin level is picking up your voice first.

Professional broadcast lavalier microphones, the small clip-on mics used by journalists and presenters, use the same chin-level placement for the same reason. AUDR borrows that positioning directly.

Related reading: The case for the inline mic, in plain words.

Passive noise isolation

Passive noise isolation is noise reduction created by the physical seal of the ear tip in your ear, without microphones, processors, or a battery.

Noise reduction that does not use any electronics. It works through the physical fit of the earbud in your ear. When the ear tip creates a seal, it blocks outside sound the way a good pair of earplugs would, by physically preventing sound waves from getting through.

Passive isolation is different from active noise cancellation, which uses a microphone to pick up ambient sound and a processor to generate an opposing signal that cancels it out. Active noise cancellation requires a battery. Passive noise isolation requires nothing. It just requires a good fit.

For most everyday environments, a well-fitted passive seal blocks enough ambient noise to make calls and music comfortable. In very loud environments like planes or construction sites, active noise cancellation has the edge. For a desk, a commute, or a coffee shop, passive isolation is enough and costs nothing in battery life.

AUDR uses passive noise isolation. No battery, no processor, no firmware involved.

Related reading: Why we put the mic before the drivers .

USB-C audio

USB-C audio is audio transmitted through a USB-C connector instead of a 3.5mm headphone jack, letting modern devices handle power and digital audio through one port.

Audio transmitted through a USB-C connector rather than a 3.5mm headphone jack. USB-C carries both digital audio data and power through the same port, which is why most modern phones, tablets, and laptops have moved to it as the single connector for everything.

For earphones, USB-C means the audio signal leaves your device as a digital signal and is converted to analog sound inside the earphone or at the connector. With a 3.5mm jack, that conversion happened inside the device. The practical difference for most users is minimal, but USB-C earphones do not require a separate DAC or adapter on modern devices.

The important thing for most people is compatibility. iPhone 15 and newer, most Android phones made after 2022, MacBooks, iPads, and most laptops already have USB-C. A USB-C earphone plugs directly into the device you already carry with no adapter needed.

AUDR is USB-C native for exactly this reason. The adapter era is over for most people. Plug in, it works.

Cable braid

Cable braid is the outer woven layer around the cable core. Compared with smooth rubber, a good braid tangles less and spreads stress more evenly along the cable.

The outer layer of the earphone cable. Most budget wired earphones use a smooth rubber sheath, which is cheap to manufacture, flexible, and tangles constantly because rubber has memory. It holds the shape of every bend it makes.

A braided cable uses fabric or nylon woven around the cable core. The weave distributes stress more evenly along the cable's length, which reduces the memory effect and means the cable comes out of a bag in roughly the shape it went in rather than in a knot.

Not all braids are equal. A thin nylon braid is better than rubber but tends to fray at the connection points. A medium-weight fabric braid handles drops, daily coiling, and pocket carry without failing at the connectors. A heavy fabric braid is almost tangle-proof but too stiff and heavy for earphones you want to carry in a pocket.

AUDR uses a medium-weight fabric braid, the same material used in studio audio equipment cables, with reinforced strain relief at every connection point.

Related reading: The cable braid: how we picked one out of four.

Strain relief

Strain relief is the reinforced section where the cable meets the plug, splitter, or earbuds, designed to prevent sharp bending at the most failure-prone joints.

The reinforced section at the points where the cable meets a connector, typically at the plug, the splitter, and the earbuds themselves. Strain relief is the part that prevents the cable from bending sharply at those joints, which is where most cable failures start.

On a cheap cable, strain relief is a thin rubber boot that cracks within months of daily bending. On a well-built cable, it is a solid reinforced section that moves with the cable rather than fighting it. The difference is not visible when you buy, but it becomes obvious about six months into daily use.

Most wired earphones fail at the connector, not at the driver. Strain relief is the detail that extends cable life significantly.

Lossless audio

Lossless audio is audio that reaches your ears without compression, meaning the full data of the original recording is preserved.

Audio that has not been compressed. The full data from the original recording reaches your ears without any information removed or approximated.

The opposite is lossy audio, which Bluetooth uses by default. Bluetooth has limited wireless bandwidth and cannot carry a full audio signal in real time, so it compresses the signal before transmitting it. The default Bluetooth codec, SBC, transmits at 192 to 328 kilobits per second. A standard uncompressed CD-quality audio file runs at 1,411 kilobits per second. That is more than four times the data. The detail that does not fit through the Bluetooth pipeline does not reach your ears.

A wired connection carries the full uncompressed signal directly from your device to the drivers. No compression step. What was recorded is what you hear.

The difference is most noticeable on acoustic music, live recordings, and voice content. On top-40 pop in a noisy environment, most people cannot tell. On a quiet evening listening to something recorded with care, most people can.

Related reading: Why wired sounds different (without getting weird about it) .

SBC (Sub-band Coding)

SBC is the default Bluetooth audio codec used when no higher-quality codec is negotiated between the source device and the earbuds.

The default Bluetooth audio codec. When your phone connects to wireless earbuds and no higher-quality codec is negotiated, SBC is what handles the audio transmission.

SBC transmits at 192 to 328 kilobits per second. It is functional and broadly compatible, which is why it became the default. It is also the lowest-quality Bluetooth codec in common use. Most wireless earbuds operate on SBC most of the time, regardless of what the marketing says about supported codecs.

Higher-quality Bluetooth codecs exist. LDAC reaches up to 990 kilobits per second. aptX HD reaches around 576 kilobits per second. Both are significantly better than SBC. Neither reaches the 1,411 kilobits per second of uncompressed audio, and both require the device and the earbuds to both support the same codec for the higher quality to activate.

Wired audio bypasses all of this entirely.

Related reading: Why wired sounds different (without getting weird about it) .

Latency

Latency is the delay between the audio signal leaving your device and reaching your ears, usually measured in milliseconds.

The delay between the audio signal leaving your device and reaching your ears. Measured in milliseconds.

Wired audio latency is under 5 milliseconds, which is effectively imperceptible. Bluetooth SBC latency runs between 150 and 200 milliseconds. That is roughly a fifth of a second.

For music listening, Bluetooth latency is usually fine because the audio and visuals you are watching are often synchronized at the software level. For calls and video, the delay is real and noticeable on the other end. It is one reason voices sound slightly processed through wireless earbuds on calls. Your voice is compressed, delayed, and reconstructed before it reaches the other person.

A wired mic at under 5ms sends your voice directly to the phone. No delay, no reconstruction.

Drivers

Drivers are the components inside the earbud that convert an electrical signal into sound, similar to mini speakers.

The components inside the earbud that convert an electrical signal into sound. Drivers are to earphones what speakers are to a sound system. The size, material, and tuning of the drivers determine how the earphone sounds.

Most consumer earphones use dynamic drivers, which work like a miniature speaker, a magnet, a voice coil, and a diaphragm that moves air to produce sound. Some higher-end earphones use balanced armature drivers, which are smaller and more precise but respond differently across the frequency range.

Driver quality matters, but it is not the only thing that matters. A well-tuned average driver sounds better than a poorly tuned premium driver. Tuning is the process of calibrating how the driver responds across the frequency range, how much bass, how much treble, how the midrange sits, to produce a sound that is faithful to the recording rather than artificially boosted anywhere.

AUDR tunes its drivers for balanced sound across voice, music, and video. Not bass-heavy. Not artificially bright. Honest to the source.

Frequency response

Frequency response describes how an earphone reproduces bass, mids, and treble across the audible range.

How an earphone reproduces different frequencies of sound, from bass at the low end to treble at the high end. Usually shown as a graph with frequency on the horizontal axis and loudness on the vertical axis.

A flat frequency response means every frequency is reproduced at roughly the same volume, which is faithful to the original recording. Most consumer earphones boost the bass and sometimes the treble because boosted bass sounds impressive in a first listen. Over a full day of listening, a more balanced response is easier on the ears.

You do not need to read frequency response graphs to understand this. The practical test is simple. Put on something you know well. Does the bass overpower the voices? Do the high frequencies feel sharp or harsh after an hour? If the answer to either is yes, the tuning is working against you.

Wind mesh

Wind mesh is a small layer of foam or mesh placed over a microphone capsule to reduce rumble from moving air.

A small layer of acoustic foam or mesh material placed over the microphone capsule to reduce wind noise. The same material and concept used on professional outdoor microphones.

Without a wind mesh, any breeze across the mic creates a low rumbling noise that can make a voice on a call sound like it is being recorded in a storm. A good wind mesh blocks that noise without meaningfully affecting voice pickup.

AUDR includes a wind mesh on the inline mic specifically for outdoor use, calls taken on a walk, a windy platform, outside a building. It is a small detail that makes a significant difference to the person on the other end of the call.

Codec

Codec stands for coder-decoder, the algorithm that compresses audio for wireless transmission and decompresses it for playback.

Short for coder-decoder. In audio, a codec is the algorithm that compresses audio for wireless transmission and then decompresses it at the other end for playback.

Bluetooth codecs include SBC (lowest quality, universal compatibility), AAC (used by Apple devices), aptX and aptX HD (used by many Android devices), and LDAC (highest quality Bluetooth codec, developed by Sony). Each codec has different bitrate limits and different compatibility requirements.

For a higher-quality Bluetooth codec to work, both the transmitting device and the receiving earbuds need to support the same codec. If they do not match, the connection defaults to SBC.

Wired earphones do not use a codec. The audio signal travels directly from the device to the drivers without any encoding or decoding step. The codec question is simply not relevant.

Ear tips

Ear tips are the silicone or foam pieces that fit into the ear canal and strongly affect comfort, seal, bass response, and passive isolation.

The soft silicone or foam pieces that attach to the end of an in-ear earphone and sit in the ear canal. They come in different sizes, usually small, medium, and large, and the right fit affects both comfort and sound quality significantly.

A well-fitted ear tip creates a seal in the ear canal. That seal is what provides passive noise isolation. It also affects bass response, because a loose fit allows low frequencies to escape before they reach the eardrum. The same earphone can sound noticeably different with a poor seal versus a good one.

Most people use the medium ear tips that come pre-fitted and never change them. Taking five minutes to try the other sizes often improves both comfort and sound quality noticeably.

Repairability

Repairability is the degree to which a product can be maintained, repaired, or have parts replaced by the user or a repair service.

The degree to which a product can be maintained, repaired, or have components replaced by the user or a repair service. iFixit, which independently tests consumer electronics, scores products from 0 to 10 on repairability.

Most wireless earbuds score 0 out of 10. The batteries are glued in, the housings are sealed with adhesive, and there are no user-serviceable parts. When the battery degrades after 300 to 500 charge cycles, typically 12 to 24 months of daily use, the product is effectively at end of life. Repair is not a realistic option.

Wired earphones have no battery to degrade. The components that wear are physical: the cable sheath, the strain relief, the ear tips. These are visible, predictable failure points. A cable that frays is a problem you can see coming. A battery that loses 30% of its capacity over 18 months is invisible until it is already affecting your day.

Related reading: The wireless tax.

3.5mm jack (headphone jack)

The 3.5mm jack is the long-standard circular analog audio connector once common on phones, laptops, and audio gear.

The circular audio connector that was standard on phones, laptops, and audio equipment for decades. The small metal plug, 3.5mm in diameter, carried analog audio directly from the device to the earphone.

Apple removed the headphone jack from the iPhone in 2016. Most Android manufacturers followed over the following years. The removal pushed people toward wireless earbuds or toward USB-C wired earphones. USB-C earphones now serve the same purpose on modern devices, without the need for an adapter.

Some devices still have a 3.5mm jack, including many laptops, older phones, and audio equipment. If you need to use a 3.5mm earphone on a USB-C device, a USB-C to 3.5mm adapter works fine.