Room tone atlas

Record a room consistently and document what changes between two background-sound recordings.

GUIDED LESSON

Start here

This is a recording lesson, not a populated map of room recordings. Use it to prepare a recording with enough context for a meaningful later comparison.

By the end: Make two labelled takes with consistent gain and position, then separate environmental changes from recording changes.

What you need: A phone or recorder, headphones and a place where recording is permitted. Avoid capturing private conversations.

Before you begin: A phone or recorder, a quiet place you may record, and headphones for review.

How to work through this lesson

Support the recorder and note its device, gain, position and orientation. Record 30 seconds without handling it.
Change one ordinary background source you control, such as a fan, then make another 30-second take with the same setup.
Listen to both at the same playback setting. Note handling noise and automatic gain before attributing a level difference to the room.

Record a place without inventing silence

Room tone is the background sound of a location under stated conditions. It may contain ventilation, distant traffic and equipment noise. Calling it silence hides the information you want to preserve.

Keep microphone position and recording settings fixed during a take. Document whether automatic gain or noise reduction was active. These processes can alter the background between recordings and make a location comparison misleading.

Worked example

Original collection protocol: record 30 seconds with the recorder supported, then another 30 seconds after switching off an ordinary fan you control. Keep distance, gain and orientation the same; leave any essential equipment alone. Label the files with date, room, device and fan state. Listen for a stable background change and for handling noise at the start.

Try it yourself

Write your answer before opening the explanation. Use the worked example if you get stuck.

Question 1

The second take sounds louder even though the fan is off. Give two plausible explanations and a follow-up test.

Show answer and reasoning

Automatic gain may have raised the remaining noise, or another source may have changed between takes. Check the recording settings and repeat in a short alternating sequence. Compare fixed-gain recordings where the device permits it, and record uncontrolled changes rather than hiding them.

Watch for: A phone’s processed recording is not an acoustically calibrated measurement. Obtain permission before recording people or private spaces.

Summary + next step

Make two labelled takes with consistent gain and position, then separate environmental changes from recording changes.

Keep the result: Keep originals with general location/context, date, device/gain, processing and recording permission. Keep a separate edited listening copy.

Measure and compare your recordings locally →

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