<?xml version="1.0" encoding="UTF-8"?>
<svg width="980" height="720" viewBox="0 0 980 720"
     xmlns="http://www.w3.org/2000/svg"
     font-family="Arial, sans-serif">
 
  <!-- Background -->
  <rect width="100%" height="100%" fill="#ffffff"/>
 
  <!-- Title -->
  <text x="490" y="50" text-anchor="middle"
        font-size="30" font-weight="bold">
    Echo Matrix — Families × Substrates × Stability
  </text>
 
  <!-- Column Labels (Substrates) -->
  <g font-size="20" font-weight="bold">
    <text x="240" y="110" text-anchor="middle">S</text>
    <text x="380" y="110" text-anchor="middle">C</text>
    <text x="520" y="110" text-anchor="middle">H</text>
    <text x="660" y="110" text-anchor="middle">So</text>
    <text x="800" y="110" text-anchor="middle">A</text>
  </g>
 
  <!-- Row Labels (Echo Families) -->
  <g font-size="20" font-weight="bold">
    <text x="120" y="170">F1</text>
    <text x="120" y="240">F2</text>
    <text x="120" y="310">F3</text>
    <text x="120" y="380">F4</text>
    <text x="120" y="450">F5</text>
    <text x="120" y="520">F6</text>
  </g>
 
  <!-- Grid -->
  <g stroke="#000" stroke-width="2">
    <!-- Horizontal lines -->
    <line x1="180" y1="130" x2="900" y2="130"/>
    <line x1="180" y1="200" x2="900" y2="200"/>
    <line x1="180" y1="270" x2="900" y2="270"/>
    <line x1="180" y1="340" x2="900" y2="340"/>
    <line x1="180" y1="410" x2="900" y2="410"/>
    <line x1="180" y1="480" x2="900" y2="480"/>
    <line x1="180" y1="550" x2="900" y2="550"/>
 
    <!-- Vertical lines -->
    <line x1="180" y1="130" x2="180" y2="550"/>
    <line x1="300" y1="130" x2="300" y2="550"/>
    <line x1="440" y1="130" x2="440" y2="550"/>
    <line x1="580" y1="130" x2="580" y2="550"/>
    <line x1="720" y1="130" x2="720" y2="550"/>
    <line x1="900" y1="130" x2="900" y2="550"/>
  </g>
 
  <!-- Matrix Content (Canonical Echo Placement) -->
  <g font-size="18">
 
    <!-- F1 Structural -->
    <text x="240" y="170" text-anchor="middle">●</text>
    <text x="380" y="170" text-anchor="middle">●</text>
 
    <!-- F2 Harmonic -->
    <text x="520" y="240" text-anchor="middle">●</text>
 
    <!-- F3 Substrate -->
    <text x="240" y="310" text-anchor="middle">●</text>
    <text x="380" y="310" text-anchor="middle">●</text>
    <text x="520" y="310" text-anchor="middle">●</text>
    <text x="660" y="310" text-anchor="middle">●</text>
 
    <!-- F4 Recursion -->
    <text x="520" y="380" text-anchor="middle">●</text>
    <text x="660" y="380" text-anchor="middle">●</text>
    <text x="800" y="380" text-anchor="middle">●</text>
 
    <!-- F5 Drift-Shadow -->
    <text x="240" y="450" text-anchor="middle">●</text>
    <text x="520" y="450" text-anchor="middle">●</text>
    <text x="800" y="450" text-anchor="middle">●</text>
 
    <!-- F6 Atlas -->
    <text x="800" y="520" text-anchor="middle">●</text>
 
  </g>
 
  <!-- Legend -->
  <g font-size="16">
    <text x="180" y="600">● = Echo presence</text>
    <text x="180" y="630">F1–F6 = Echo Families</text>
    <text x="180" y="660">S, C, H, So, A = Substrates</text>
  </g>
 
</svg>