Comfortable sound for guests, the right RT60, no noise — turnkey.
In a restaurant the listener barely hears the «direct» sound from the speaker. Beyond the critical distance the reflected field dominates — what bounced back off the walls, glass, and ceiling. Per Harman research measurements (Toole), the contribution of direct sound to perception is about 14%, while early and late reflections each contribute ~44%. That is, 86% of the sound quality in the room is decided by the space, not the «box.»
This leads to a direct conclusion: a flat, even response of the speaker itself does not equal even sound at the guest’s ear (Toole, JAES). You can install speakers worth millions — in a boomy room they will drown in their own reflections. First you have to fix the room, then deal with directivity and source placement.
RT60 is the time it takes for sound in a space to decay by 60 decibels. For residential and small spaces the normal range is 0.3–0.6 seconds (RoomPerfect / Lyngdorf methodology). Concert halls and large boomy spaces live in the 1.5–5 second range. A «bare» restaurant with concrete, glass, and tile after renovation is closer to the second in character: a long reverberation «tail» overlays one table’s voices onto the next.
Then a chain reaction kicks in: to overcome the noise the guest speaks louder, the next table repeats it, and twenty minutes later the whole room is shouting at itself. The goal of treatment is to shorten the «tail» to values at which a voice at the table stays intelligible and background music doesn’t merge with speech into general noise.
The «buy a pack of panels and stick them on the wall» scheme doesn’t work. Without calculation the material lands in a zone where it barely affects reverberation, while the problem frequencies remain. The RoomPerfect (Lyngdorf) methodology states the rule directly: measurement separates the signature of the system itself from the room’s acoustic problems, and you should correct only the damage the room does, not impose an abstract «flat» curve on the space.
That’s why we run the project by measurement, not «by eye.» The standard sine-based Thiele–Small method (1965) yields a final-tuning efficiency of just 1.5–5%. We work with the impulse response — one measurement captures the behavior of every band over time: where the room «booms,» at which frequencies energy accumulates, what material is needed and where.
In a restaurant the reflection problem is solved not by the number of sources but by control of their directivity. A controlled pattern (for example, cardioid — measured on Kii and Dutch&Dutch systems on Klippel rigs) sets the ratio of direct to reflected field: the system sends energy to where the guest sits and barely «hits» the walls and ceiling.
By measurement, a directional system’s rear radiation in the midrange is 10–15 dB lower than the front (Erin’s Audio Corner, Klippel NFS). Above the room’s transition frequency, dispersion control really does improve speech intelligibility and reduce the audibility of reflections — a confirmed effect, not marketing. Smart placement of such sources gives even coverage across tables with no «loud» or «dead» zones.
A closed loop: from the first measurement to an acoustic passport of the room with numbers. No «blind» work — everything rests on measurements of the space.
Because beyond the critical distance the guest mostly hears the reflected field, not direct sound. Per Harman (Toole), the contribution of direct sound to perception is about 14%, while early and late reflections are ~44% each. A flat response of the speaker itself does not equal even sound at the ear in a real room. First you must fix the room’s reverberation, then deal with the sources.
A target for a comfortable room is closer to the range of residential and small spaces, 0.3–0.6 seconds (RoomPerfect / Lyngdorf methodology), whereas large boomy halls live in 1.5–5 seconds. A «bare» restaurant after renovation is closer to the second in character. We set the specific RT60 target for the room format, measure before and after the work, and record the figure in the acoustic passport.
A sound-level meter shows only the overall level in decibels. The impulse response gives the room’s behavior over time across all octaves in one measurement — you can see at which frequencies the room «booms» and what material is needed in which zone. The sine-based Thiele–Small method (1965) gives a tuning efficiency of just 1.5–5%, so we don’t use it as the basis for calculation.
Yes. We split the work into night shifts or closed days and don’t touch the kitchen or service — in the morning the room is open for guests. We match materials to the design: textured wall panels, ceiling cassettes in matching colors, hidden absorption behind decorative grilles and fabric. The goal is for the guest to hear clean sound and never suspect that acoustic treatment is installed in the room.
Describe the space and the format — we’ll reply within 2 hours with a preliminary estimate