In short: Send a 1 kHz tone down your chain and set each recorder and camera input so the tone reads -18 dBFS, so every meter agrees. Then play pink noise through the monitors to judge the room, and a sweep to find dips, peaks and rattles, starting at a low volume. Record each test and keep the notes with the sound report.
A test pack gives you signals whose correct result you already know. A tone tells you whether your levels sit where they should. Pink noise tells you what the room and the monitors do to sound. A sweep shows whether any part of the chain colours the sound. Run them in that order each time the kit changes, and most faults show up before the first take.
The pack is a set of WAV files, so it plays from any recorder or laptop. It holds six files, all 48 kHz, 24-bit mono: 100 Hz, 1 kHz and 10 kHz tones at -18 dBFS, a 1 kHz tone at -20 dBFS for kit lined up to the US SMPTE standard, 30 seconds of pink noise at -18 dBFS and a logarithmic sweep from 20 Hz to 20 kHz. The levels are RMS, so a -18 dBFS tone peaks at -15 dBFS. Use the RMS or VU-style reading on a meter that offers one, and expect a peak-reading meter to show -15.
What each test tells you
A 1 kHz tone is a steady sine wave. Its job is to line up levels between devices. Feed it from the mixer or a laptop into the recorder and into any camera taking a feed, and set each input so the tone reads -18 dBFS. Every meter in the chain then agrees, so a level on one means the same on the others. Microphone gain is still set from the voice. The -18 dBFS figure is the alignment level for digital test tones in EBU recommendations, so a file set this way matches what broadcast engineers expect to see.
Pink noise has the same energy in each octave, so it sounds even to the ear. Play it through the monitors in the room you will work in, at a comfortable level, and listen for a band that sticks out. A boomy low end or a harsh top usually means the speakers sit too close to a hard wall or in a corner. Fixing that takes minutes now and hours later in the edit.
A sweep runs slowly through the audible range. One pass shows a dip or a lump anywhere in the chain, which matters most with a new cable, a borrowed preamp or headphones you do not know.
A routine for the morning
- Connect the chain exactly as you will use it on the day, with the same cables, microphone or line input and monitoring.
- Play the tone into the recorder and any camera feed, and set each input to -18 dBFS. Record ten seconds and label the file.
- Play pink noise through the monitors, starting with the volume low, because tones and sweeps at full level can damage speakers and hearing. Bring it up to a comfortable level, walk around the room and listen for a band that jumps out.
- Play one sweep through the chain. Listen on headphones and on the monitors, and note any point where the sound thins or booms.
- Write the results on a sound report, with the date, the sample rate and the kit list.
Worked example
A recordist sets up a boom, a recorder and a feed to the camera for a two-hour interview. The mixer's tone reads -18 dBFS on the recorder and on the camera, so the camera's guide track will match. The boom gain is then set from the interviewee's voice. Pink noise sounds harsh near the hard back wall, so the monitors move to the other side of the room. The sweep shows nothing odd on the headphones. The notes go on the sound report before the interviewee sits down.
Common mistakes
- Changing the line-up halfway through the day. Once the recorder and camera inputs are matched on the tone, leave them, ride the microphone levels on the mixer, and note any change on the sound report.
- Normalising a test file. Normalising changes the level, so the tone no longer reads -18 dBFS. Keep the file as it is.
- Testing at the wrong sample rate. Test at the rate you record. If the session runs at 48 kHz, the tone should too.
- Judging the room on headphones. Pink noise through headphones tells you about the headphones. Play it through the room as well.
- Leaving the take unlabelled. A test file with no date or kit name is of no use on the next job.
If you want a room that is already set up for this kind of checking, the studio hire page explains what each space includes. For speech in particular, the location sound starter and the timecode and sync guide cover the same ground from the microphone outwards, and the podcast test pack applies these tests to a speech set-up.
Sources
- Wikipedia, Alignment level, read 5 November 2026
Related guides
- Location sound starter: boom, lav, room tone
- Lav placement: where to clip a lavalier microphone
- Sound report template, with a worked example
- Timecode and sync explained, with an LTC test file
- How does remote ADR work?
- All guides and tools
The picture at the top of this page is an illustration, not a photograph of a client or a real job.
Questions we get asked
What level should a test tone be set to?
Set it to -18 dBFS on a digital recorder, the alignment level in EBU recommendations. Use it to make every device in the chain read the same, leave that line-up alone for the day, and set microphone gain from the voice itself.
What is pink noise used for?
Pink noise carries the same energy in each octave, so it sounds even to the ear. Play it through the monitors in the room and listen for a band that booms or harshens. Move the speakers or treat the room before you trust what you hear.
Why use a sweep if I have a tone?
A tone checks one frequency. A sweep runs through the audible range, so one pass can show a dip or a lump anywhere in the chain, from the cable to the headphones.
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