# Placement & SPL — 300-person church

## Goals

- Speech clarity (STI-oriented): prioritize 500 Hz–4 kHz  
- Comfortable sermon level ≈ **65–75 dBA** at pews  
- Headroom ≥ 10 dB for peaks / music beds  

## CAMS-1 capability (order-of-magnitude)

| Condition | Level |
|-----------|--------|
| Sensitivity mid (typ.) | ~90–93 dB / 2.83 V / 1 m |
| Amp mid continuous | ~40–50 W into 8 Ω |
| Peak @ 1 m | ~108–112 dB |
| Continuous @ 1 m | ~104–107 dB |

Distance loss ≈ 6 dB per doubling in free field (less in reverberant churches).

| Distance | Approx continuous (one speaker) |
|----------|----------------------------------|
| 2 m | ~100 dB |
| 4 m | ~94 dB |
| 8 m | ~88 dB |
| 12 m | ~84 dB |

For **300 people**, typical sanctuary depth 12–20 m:

- **Recommended:** **two** CAMS-1 (L/R) or one CAMS-1 as **center vocal fill** under existing mains.  
- **Single unit:** place on stand **ahead of first pews**, HF aimed at last third of seating; keep volume so farthest seats ≥ 65 dBA without forcing clip.  

## Aiming

1. HF axis toward ear height of rear congregation (~1.1–1.2 m seated).  
2. Avoid aiming into bare parallel walls (slap-back).  
3. Use HF trim pot to tame harshness if sanctuary is reflective.  

## Mixer gain structure

1. Desk output +4 dBu nominal → CAMS input.  
2. CAMS master at 12–2 o’clock; structure gain so clip never lights on speech peaks.  
3. Optional external compressor/limiter before CAMS for pastors who vary level.  

## VERIFY on site

- Walk the room with speech program; note dead spots.  
- Check for stand tip hazard in aisles.  
- Confirm residual hum (ground lift only on DI — not by lifting IEC earth).
