For teachers and course creators
Lecture audio cleanup
Clean the voice in recorded lectures and course videos so students hear the lesson, not the room.
Cleaned on your own device — the file is never uploaded.
The problem
What gets in the way
Lectures are recorded in real classrooms and home offices, often hours at a time, with the mic far from the speaker. Students end up straining to hear over projector fans and shuffling, and each lesson plays at a different volume.
- Projector and computer fans
- Air conditioning and heating
- Chairs, footsteps and shuffling paper
- Murmur from students in the room
What you get
A clean voice, ready to use
- A clearer teacher’s voice, with room noise removed
- Video lectures back in their own format, picture untouched
- The same loudness across every lesson
- Long recordings handled in one go, up to your plan’s limit
How it works
Four steps, one clean file
Step 1: Pick your settings
Set Loudness to Podcast (−16 LUFS) for every lesson, so the whole course plays at one level.
Step 2: Drop a lesson
Drop the lecture video (MP4, MOV, WebM, MKV) or audio file. Clean lessons one after another.
Step 3: Let it clean
Your browser cleans the lesson on your own computer and it is never uploaded. The first file takes a little longer while our speech AI loads.
Step 4: Compare and keep it
The clean lesson downloads by itself when it is ready. Play the A/B preview to switch between original and cleaned at the same moment, or change a setting and choose Download again.
For this recording
Recommended settings
- Loudness
- Podcast (−16 LUFS)
- Output format
- Same as original
One loudness for every lesson stops students reaching for the volume between videos, and the built-in voice clarity helps a distant mic sound closer.
Set them in the tool before you add the file: they are used for the automatic download, and you can change them afterwards and download again.
Good to know
- Echo and room reverb stay as recorded: it removes noise, not the sound of the room.
- Questions from students far from the mic are kept but may sound quieter than the teacher.
Formats & limits
What goes in, what comes out
- MP4
- MOV
- WebM
- MKV
- WAV
- MP3
- M4A
- AAC
- FLAC
- OGG
- Opus
Same as original: video lectures keep their container and picture; audio comes back in its own format or as WAV.
- MP3, M4A and video audio tracks are written in mono at about the source bitrate (at least 160 kbps): the cleaned voice sits in the centre.
A free account cleans 30 minutes a month, no card needed. The paid plans, Creator (9 hours), Pro (30 hours) and Studio (100 hours) a month, take files up to 3 hours and 4 GB each. See pricing
FAQ
Common questions
Can it clean a whole lecture at once?
Yes. Long recordings are cleaned in one go and the progress bar shows the time left. The longest file you can clean depends on your plan; see the limits on this page.
Will the slides in my video change?
No. The picture is copied as it is; only the audio track is replaced.
How do I get every lesson to the same volume?
Use the same Loudness setting for every file. Each lesson is measured and set to that level, so the whole course plays evenly.
Is my file uploaded?
No. The cleaning runs inside your browser, on your own computer. Your audio and video never leave your device; our server only receives the file’s length and format to check your allowance.
Is it free?
A free account cleans 30 minutes a month, no card needed. The paid plans, Creator (9 hours), Pro (30 hours) and Studio (100 hours) a month, take files up to 3 hours and 4 GB each. See the pricing page for details.
Related
Other recordings we clean
Clean up Zoom and meeting recordings
Take typing, fans and room noise out of recorded Zoom, Teams and Meet calls.
See howRemove background noise from video
Clean the voice in MP4, MOV, WebM or MKV while the picture stays untouched.
See howVoice-over noise removal
Clean home-studio takes and get a sample-aligned WAV, ready to mix.
See how
Ready for a clean take?
Drop a recording and hear the difference in seconds. Create a free account, no card needed.
Try it free