# Resonance & Dead Spot Diagnosis

Logic rules for identifying structural resonance issues (Wolf tones).

## Symbols

- `Dead_Spot`: Note decays rapidly (low sustain).
- `Wolf_Tone`: Note blooms loudly then stutters/warbles.
- `Frequency_Match`: Played note matches the body's resonant frequency.
- `Bridge_Loose`: Bridge wings or center not fully glued.
- `Brace_Loose`: Internal bracing has lifted.
- `Neck_Joint_Gap`: Poor contact in neck pocket/dovetail.

## Logic Rules

### 1. The Classic Dead Spot (G string, 7th-9th fret)
**Condition:** `Dead_Spot` AND (`Note_G` OR `Note_G#`)
**Logic:** `Dead_Spot_G → (Frequency_Match ∨ Neck_Resonance)`
**Diagnostic Step:**
1.  **Mass Loading:** Add clamp/weight to headstock.
2.  **Result:** If dead spot moves to a different fret → Headstock/Neck Resonance.
3.  **Result:** If dead spot persists → Body Resonance (Top/Back coupling).

### 2. Structural Damping
**Condition:** `Dead_Spot_Random`
**Logic:** `Dead_Spot_Random → (Bridge_Loose ∨ Brace_Loose ∨ Neck_Joint_Gap)`
**Diagnostic Step:**
1.  **Tap Test:** Tap bridge/top. Listen for "clack" or rattle.
2.  **Paper Test:** Try to slide paper under bridge corners.
3.  **Result:** Paper fits → `Bridge_Loose`.

### 3. Wolf Tone (Cello/Archtop)
**Condition:** `Wolf_Tone`
**Logic:** `Wolf_Tone → Body_Resonance_High_Q`
**Diagnostic Step:**
1.  Squeeze the lower bout sides with knees/arm.
2.  **Result:** If Wolf disappears → Side/Back resonance coupling.
3.  **Remedy:** Wolf eliminator weight or internal side struts.
