VO Live
B304 — Voiceover recording booth — The quietest room in the facility
Use Cases
Voiceover recording, vocal takes, singing, spoken word, podcasting, ADR (Automated Dialogue Replacement).
VO/singing hybrid mode: Manual acoustic curtain on north wall switches room character. Curtain CLOSED = VO mode (fully absorptive, RT60 0.20s, NC-12). Curtain OPEN = singing mode (vinyl floor ambience for vocalist, RT60 0.27s).
Requires NC-12 — the strictest noise criteria in the facility. This room is designed for the most noise-sensitive content where even subtle HVAC hum would be audible on recordings.
Room Data
| Parameter | Value |
|---|---|
| Room code | B304 |
| Width (south) | 275 cm |
| Width (north) | 327 cm |
| Width (avg) | 301 cm |
| Depth | 176 cm |
| Area | 5.31 m² |
| Volume | 14.60 m³ |
| Ceiling AFF | 275 cm [AC] |
| Flooring | Vinyl |
| NC target | NC-12 |
| RT60 achieved | 0.20s (broadband) |
| Schroeder freq | 234 Hz |
| IDU | IDU-04 (dedicated) |
Floor Plan Position
VO Live occupies the northwest corner of the zone. Bounded by concrete walls on north (W1) and west (W2, diagonal), the buffer spine (W5) on the east, and the VO/Control partition (W6) on the south.
The observation window OW-1 (STC 50) is located in the south wall (W6), providing visual contact with the Control Room.
Room Footprint
Acoustic Treatment
| Element | Qty | Specification |
|---|---|---|
| Absorption panels | 8 | Rockwool RWA45 50mm, 1200×600mm, NRC 0.90 |
| Bass traps | 4 | Rockwool RWA45 150mm, floor-to-ceiling, corners |
| QRD diffusers | 0 | — |
| Ceiling | Full | Rockfon Sonar E, NRC 0.90 |
| Motorized curtain | 1 | 450g/m² velour, ceiling C-rail, dead/live positions |
RT60 Analysis
| Band | Target (s) | Achieved (s) | Status |
|---|---|---|---|
| 125 Hz | 0.25 | 0.28 | ✓ Pass |
| 250 Hz | 0.22 | 0.23 | ✓ Pass |
| 500 Hz | 0.20 | 0.20 | ✓ Pass |
| 1 kHz | 0.18 | 0.19 | ✓ Pass |
| 2 kHz | 0.18 | 0.18 | ✓ Pass |
| 4 kHz | 0.18 | 0.17 | ✓ Pass |
Room Modes
| Mode | Frequency |
|---|---|
| Length (L) | 57.0 Hz |
| Width (W) | 97.3 Hz |
| Height (H) | 62.4 Hz |
| Schroeder | 234 Hz |
Noise Criteria
Target: NC-12 — the quietest achievable rating for this room type.
| Octave (Hz) | 63 | 125 | 250 | 500 | 1k | 2k | 4k | 8k |
|---|---|---|---|---|---|---|---|---|
| NC-12 limit (dB) | 51 | 40 | 33 | 26 | 22 | 19 | 17 | 16 |
Boundary Build-ups
| Wall | Type | Lab STC | Field | Assembly |
|---|---|---|---|---|
| North (W1) | Concrete | 65 | 58–62 | 300mm concrete + RSIC-1 + 50mm RW + 2×gyp |
| South (W6) | Partition | 53 | 47–51 | VO/Control partition (obs. window OW-1 here) |
| East (W5) | Buffer spine | 55 | 49–53 | 2×12.5mm gyp+GG + 100mm studs+RW + 2×12.5mm gyp+GG |
| West (W2) | Diagonal concrete | 65 | 58–62 | RSIC-V clips |
| Ceiling | Rockfon Sonar E | — | — | NRC 0.90, 275cm AFF |
| Floor | Float | — | — | Vinyl finish + 15cm Sylomer buildup |
HVAC — Silencer Run A
| Parameter | Value |
|---|---|
| IDU | IDU-04 (dedicated to VO Live only) |
| Silencer | Run A: 1500mm, 40dB attenuation |
| Max velocity | 1.5 m/s |
| NC contribution max | NC-12 |
| Risk R1 | IDU-04 self-noise must be verified at min fan speed [AC] |
NC-12 demands ≤35 dB SPL at 4kHz octave band. IDU-04 supply and return ducts MUST have inline rectangular silencers (minimum 900mm length, 50mm Rockwool lining). Without silencers, IDU-04 alone will produce approximately NC-28 at the diffuser — 16 dB above target. This is non-negotiable for the NC-12 specification.
Design Constraints [AC]
- [AC] NC-12 is achieved ONLY if IDU-04 runs at minimum fan speed — verify at commissioning
- [AC] Perimeter gap 25mm → backing rod → Tremco MUST NOT be bridged
- [AC] 4 bass traps required in corners — cannot be removed
- Motorized curtain allows live (0.27s) vs dead (0.20s) mode switching
- Observation window OW-1 (STC 50) is the weakest acoustic element in Wall W6 (STC 53)