Clothing Rustle and Cable Thumps: Getting Clean Sound From a Lavalier

The kinds of noise a lavalier picks up

A lavalier sits on the body, so it hears the body and clothing as well as the voice. Different noises have different causes, and identifying which one you have is the first step:

Clothing rustle

A scratchy, papery sound when fabric brushes over or near the capsule. Rises and falls with gestures and breathing

Contact noise

Rubbing or scraping when the microphone itself touches skin, chest hair, a beard, a necklace or a lanyard

Cable thumps

Dull knocks when the cable is tugged, swings or rubs against clothing. The cable carries vibration to the capsule

Clip and mount noise

Clicks or rattles from a loose clip, or from a hard clip vibrating against a button

Wireless problems

Hiss, crackles, brief silences or bursts of noise from radio interference, weak signal or low batteries

Rustle and contact noise are the most damaging because they share frequencies with speech. Cable thumps are mostly low frequency and easier to reduce afterwards. Wireless faults are a separate topic and are covered briefly below.

Placement that keeps noise down

The usual position is the center of the chest, somewhere around a hand's width below the chin, on the breastbone or a shirt placket. Clothing tends to move less there than at the collar or the side of the chest, and the distance gives a natural tone. A few placement rules help:

• Favor the side the person will face. If an interviewee will turn toward someone off-camera on their left, place the microphone slightly to that side so the voice stays on-axis.
• Keep it away from collars that flap, ties that swing, and lanyards, scarves or necklaces that can tap it.
• Avoid putting it directly under the chin, where it picks up breath and is shadowed when the head drops.
• For visible mounting, clip it on a tie, a shirt placket between buttons, or the edge of a jacket lapel that will not fold over it.
• Check the capsule is not covered by a fold of fabric. A hidden microphone needs a small air space in front of it, not a layer of cloth pressed against it.

Choosing between lavaliers, headsets and other microphone types is covered in choosing a microphone for speech; this article assumes the lav is the right choice and focuses on making it quiet.

Mounting and taping techniques

A lavalier is quiet when nothing around it can move relative to it. That means securing three things: the microphone head, the cable just below it, and the cable's route to the transmitter or recorder.

1. Make a strain-relief loop. Below the clip, form a small loop in the cable and secure it so that a tug on the cable pulls the loop, not the capsule. On a visible clip, many crews thread the cable up through the clip and back down for the same effect.
2. Tape the cable at two or three points. Use medical or fabric tape on the inside of the shirt or directly on skin, so the cable cannot swing or rub as the person moves.
3. Route the cable away from moving parts. Run it down the inside of the shirt rather than across the front where arms pass, and keep it clear of belts and waistbands that slide.
4. For hidden mounting, sandwich the microphone. Specialized sticky mounts and small fabric or fur covers hold the capsule against the inside of clothing while keeping a little air space in front of it. A loop of soft tape folded into a triangle around the head is a common improvised version.
5. Position the transmitter or recorder securely. A belt clip or a pouch at the small of the back keeps the cable taut but not tight; a loose pack that swings will knock the cable.
6. Test with movement. Ask the person to talk while raising their arms, turning, sitting down and leaning forward. Listen on closed headphones for any scratch, click or thump.

Small covers designed for lavaliers also reduce light air movement and a little contact noise. They are not a replacement for secure mounting, and outdoors they need to be the furry kind.

Fabrics, accessories and people

Some clothing is much noisier than others. As a general guide:

• Soft cotton and jersey knits are usually the quietest choices.
• Stiff synthetic fabrics such as nylon and polyester, waterproof shells, puffy jackets and starched shirts tend to rustle loudly.
• Silk and some satins slide and swish; wool and corduroy can scratch when rubbed.
• Necklaces, earrings that touch the collar, lanyards and badges cause intermittent ticks and scrapes.
• Beards and chest hair can scratch a capsule taped against skin; mount on clothing instead, or use a cover.

If you can influence wardrobe, ask presenters and interviewees to wear a soft cotton top. When you cannot, place the microphone on the outside of the garment rather than hiding it, since visible mounting is often quieter than fighting a noisy fabric.

People matter too. Speakers who gesture a lot, adjust their jacket or touch their chest when they talk will produce noise no matter how well you tape. A gentle word before recording, such as asking them not to touch the microphone area, helps more than you might expect.

Wireless interference and dropouts in brief

Wireless lavaliers add radio to the chain. Common symptoms are short silences when the signal fades, bursts of crackle or hiss from interference, and noise as batteries run low. Start each session with fresh or fully charged batteries, keep the transmitter's antenna clear of skin and metal where possible, keep the receiver within reasonable range and line of sight, and scan for a clear channel if your system supports it. Some wireless systems can also record onto the transmitter itself, which gives a backup if the radio link fails. Diagnosing gaps and glitches in recordings is covered in audio dropouts.

Repairing noisy lavalier takes

When noise has already been recorded, the options depend on the type:

• Cable thumps. Mostly low frequency, so a high-pass filter on the affected moment, or clip gain on a brief thump, usually reduces them well.
• Clicks and ticks. Repair suites often include de-click tools, and isolated ticks can be removed manually by attenuating a few milliseconds.
• Clothing rustle. Hardest to fix because it overlaps the voice. Dedicated de-rustle modules exist in some repair software and can help with mild rustle, but heavy rustle under speech rarely comes out cleanly.
• Swapping to a backup. If a camera microphone or boom recorded the same moment, editing that source into the worst seconds is often the cleanest repair. Keep backup tracks in sync for this reason.
• Re-recording. For scripted lines, a pickup recording may be quicker than repair.

Work on a copy, repair the worst moments first and compare with the original. Over-processing can leave the voice watery, which is often more distracting than a little rustle.

How rustle affects transcripts

Speech recognition models cope reasonably well with brief, isolated noises, so an occasional cable thump rarely changes the transcript. Rustle is different: when it lands on top of words, it masks consonants in the same way background noise does, and words can be misrecognized or dropped. Continuous rustle across a long passage is the worst case. If your transcript has gaps around gestures, the noise is a likely cause; why transcripts miss words covers the other common reasons.

Pitfalls to avoid

• Hiding the microphone under fabric without any air space, which muffles the voice and adds rustle.
• Taping the microphone but leaving the cable free, so every movement is transmitted to the capsule.
• Skipping the movement test because the person sat still during the sound check.
• Monitoring only at the start. Clothing shifts during a long take, and a lav can work loose.
• Relying on repair software for heavy rustle instead of fixing the mount.

Recording lavalier audio for mydubly

mydubly has no noise reduction or repair tools, so clean audio has to come from the recording or your editor. A few details of how it reads files matter for lav setups. Only one audio track is used, the file's default track, with no track picker. If your camera recorded the lav on a second track, export the video with the lav as the main or only track; multiple audio tracks in video files explains how. The soundtrack is mixed down to mono, so if the lav is on one stereo channel and a noisy camera microphone on the other, both end up in the mix; keep only the lav channel if it is cleaner.

The video picture stays on your device; only compressed audio chunks are sent for recognition. You get a plain transcript, a timestamped transcript and SRT and VTT subtitles. For interview recordings specifically, the interview transcription page covers the workflow.

Next step

Before your next shoot, do a two-minute rehearsal with the person in their actual clothing: mount, loop, tape, then ask them to move while you listen on headphones. For footage you already have, repair or replace the noisiest seconds, export with the lav as the main track, and transcribe with mydubly's video to text tool.