Room Tone Register — notes and re-checked jobs https://roomtone.top/ Dated judgements, checks and disagreements about room tone, noise floor and mains hum. Objects are not syndicated: they do not change. en 2026-09-16 09:00:00 +0000 Record room tone on set: the sixty-second routine https://roomtone.top/jobs/record-room-tone/ https://roomtone.top/jobs/record-room-tone/ 2026-09-16 09:00:00 +0000 The on-set routine for recording room tone: what to say out loud, how long to record, what to leave running, and the four things that ruin the take. Set a dialogue recording level from the room's noise floor https://roomtone.top/jobs/set-dialogue-level/ https://roomtone.top/jobs/set-dialogue-level/ 2026-09-16 09:00:00 +0000 How to choose a dialogue recording level: start from the measured floor, work out the headroom you need, and check the margin against a delivery target. An HVAC duty cycle makes a one-minute reading a lie https://roomtone.top/notes/2026-09-02-hvac-duty-cycle/ https://roomtone.top/notes/2026-09-02-hvac-duty-cycle/ 2026-09-02 09:00:00 +0000 A twelve-minute log of a treated voice room shows the air handler stepping the floor between 33 and 44 dB(A). What that means for short readings and for takes. Where a domestic refrigerator actually puts its noise https://roomtone.top/notes/2026-08-27-fridge-hum-band/ https://roomtone.top/notes/2026-08-27-fridge-hum-band/ 2026-08-27 09:00:00 +0000 A domestic fridge is not a 60 Hz hum source. Measured octave-band data from three units, and why a high-pass filter removes almost none of the audible part. What a second moving blanket actually buys you in a room https://roomtone.top/notes/2026-08-19-blanket-thickness/ https://roomtone.top/notes/2026-08-19-blanket-thickness/ 2026-08-19 09:00:00 +0000 Measured absorption for one and two layers of moving blanket, flat and with an air gap. The second layer is worth little; the gap is worth more. Why two sound meters in one room read 4.5 dB apart https://roomtone.top/notes/2026-08-11-two-meters-disagree/ https://roomtone.top/notes/2026-08-11-two-meters-disagree/ 2026-08-11 09:00:00 +0000 The same room measured with two meters gave 36.2 and 40.7 dB(A). Three causes side by side, and the check that identifies the responsible one in a minute. Two loudness targets that are not the same instruction https://roomtone.top/notes/2026-07-29-dialogue-level-argument/ https://roomtone.top/notes/2026-07-29-dialogue-level-argument/ 2026-07-29 09:00:00 +0000 A streaming target of -27 LKFS and a broadcast target of -23 LUFS differ numerically and methodologically. Why a preset cannot be copied between the two. Sabine predicted 0.42 s; the room measured 0.61 s https://roomtone.top/notes/2026-07-14-sabine-vs-measured/ https://roomtone.top/notes/2026-07-14-sabine-vs-measured/ 2026-07-14 09:00:00 +0000 A worked comparison between the Sabine prediction and a measured RT60 in a furnished room, the three reasons for the gap, and what the prediction is good for.