Quieting Conversations

A Table Decoration for
Quiet Conversations

Whether or not one knows its name, we are all familiar with the “Cocktail Party Effect”: the tendency for room noise to get louder and louder as one table after another raise their voices to be heard over those at other tables.

Should a server drop a tray, there is sudden silence, then conversation resumes quietly—but soon starts escalating again. We begin leaning towards our conversational partner and shouting. How might we prevent the escalation?

What used to be merely irritating has now become dangerous, thanks to how raising your voice can disperse four times as many virus particles. And getting closer to your conversational partner only makes it more likely they will be infected by any virus you are unknowingly spreading via invisible microdroplets[1].

While wearing a mask greatly reduces the number of outgoing viruses, masks make dining difficult. Preventing the cocktail-party-effect escalation may become essential to keeping our favorite restaurants in business.

This is a sneeze, but a loud voice generates a similar cloud of the smallest droplets
via stretching mucus between vocal cords.

One can test the concept as a conference call between cell phones (or use the audio-only versions of Skype, Zoom, Team, etc.); it is best using ear buds, with a microphone dangling on the wire, as an ear bud can block room noise.

But the goal is a low-tech setup for an entire dining room, always on and ready for dozens of quiet tabletop conversations without any plugging in or fiddling. Tall round tables could become quiet conversational hubs at cocktail parties. Think in terms of designing table decorations that contain directional microphones pointing horizontally and a speaker pointing up toward the ceiling. While some sound will be reflected back down, the path length between tables will be much longer, contributing less to room noise.

For the temporary stand-up party tables, battery power will be needed; for more permanently located tables, an overhead light might allow a thin 5V DC cable to be dropped.

Note that the device's loudness can be simply adjusted by leaning in toward the center of the table. That works when speaking as well. "Lean in!" substitutes for "Speak up!"


[1] The asymptomatic period, when an infected person is spreading the virus but not yet sick, is often as long as a week or more. And “Typhoid Mary” sickened over fifty people without getting sick herself. She denied everything and refused to take precautions even after physicians made it clear to her that she was killing people by spreading Salmonella typhi. Thus we speak of the “Typhoid Mary” Governors.

How can we keep adjacent-table conversations separated,
so that people stop raising their voices?

A conference-table speakerphone (bottom) suggests a design for a tabletop conversation hub. The speaker might need to be recessed in a can enclosure to reduce horizontal sound spread. A "flickering candle" LED could create the appearance of candlelight; it might stay lit only when the speaker's voice was within the desired loudness range. The Conversation Candle?