From 48578c5919504d65dde5c72badee6dcf6147a282 Mon Sep 17 00:00:00 2001
From: Mikei386 <44135113+Mikei386@users.noreply.github.com>
Date: Thu, 6 Aug 2026 20:53:30 +0200
Subject: [PATCH] Enable low-frequency RTW analyzer range

---
 scripts/test_gui_contracts.mjs |  5 +++++
 scripts/test_rta_profile.mjs   | 12 +++++++-----
 src/audio.rs                   | 32 +++++++++++++++++---------------
 src/rta.rs                     |  8 ++++----
 src/state.rs                   |  3 +--
 www/core/audio.js              |  2 +-
 www/core/config.js             |  2 --
 www/core/rtw_centers.js        |  5 ++++-
 www/ui/options.js              |  4 +---
 www/views/realtime.js          |  2 +-
 10 files changed, 41 insertions(+), 34 deletions(-)

diff --git a/scripts/test_gui_contracts.mjs b/scripts/test_gui_contracts.mjs
index aa3f98e..72bc7e3 100644
--- a/scripts/test_gui_contracts.mjs
+++ b/scripts/test_gui_contracts.mjs
@@ -3,6 +3,7 @@ import assert from 'node:assert/strict';
 
 const html = fs.readFileSync(new URL('../www/index.html', import.meta.url), 'utf8');
 const main = fs.readFileSync(new URL('../www/main.js', import.meta.url), 'utf8');
+const options = fs.readFileSync(new URL('../www/ui/options.js', import.meta.url), 'utf8');
 const realtime = fs.readFileSync(new URL('../www/views/realtime.js', import.meta.url), 'utf8');
 
 const styleSelect = html.match(/<select\b[^>]*\bid="styleSel"[^>]*>/)?.[0] || '';
@@ -17,5 +18,9 @@ assert((realtime.match(/applyPeakHold\(state, integrated, CONFIG, range\)/g) ||
   'every RTA engine must advance peak hold on the display clock');
 assert(/useIirEngine[^]*?applyRealtimeBarBallistics\(state, displayBase, CONFIG, range\)/.test(realtime),
   'native IIR bars must advance their visible release on the display clock');
+assert(/h\('opt_rtaFreq', v => \{\s*CONFIG\.RTA_FREQ_RANGE = \(v === 'lf'\) \? 'lf' : 'norm'/.test(options),
+  'the low-frequency range must remain selectable in the RTW layout');
+assert(!/RTA_FREQ_RANGE\s*=\s*CONFIG\.RTA_BAR_LAYOUT\s*===\s*'rtw'\s*\?\s*'norm'/.test(options),
+  'the RTW layout must not force the normal frequency range');
 
 console.log('GUI contract regression tests passed');
diff --git a/scripts/test_rta_profile.mjs b/scripts/test_rta_profile.mjs
index 5959388..a40405c 100644
--- a/scripts/test_rta_profile.mjs
+++ b/scripts/test_rta_profile.mjs
@@ -31,9 +31,9 @@ const context = vm.createContext({
   Number,
   normalizeCorrelationResponseSeconds: correlationContext.normalizeCorrelationResponseSeconds,
   getRtwCenters(mode) {
-    if (mode === '1_12') return new Array(121).fill(0);
-    if (mode === '1_6') return new Array(61).fill(0);
-    return new Array(31).fill(0);
+    if (mode === '1_12') return new Array(145).fill(0);
+    if (mode === '1_6') return new Array(73).fill(0);
+    return new Array(37).fill(0);
   },
 });
 vm.runInContext(functionSource.replace('export function', 'function'), context);
@@ -56,7 +56,7 @@ const forced = context.buildRtaRuntimeConfig({
 });
 assert.equal(forced.engine, 'iir');
 assert.equal(forced.bpo, '1_12');
-assert.equal(forced.freqRange, 'norm');
+assert.equal(forced.freqRange, 'lf');
 assert.equal(forced.order, 6);
 assert.equal(forced.detector, 'peak');
 assert.equal(forced.rtaPeakHoldMode, 'fall');
@@ -64,7 +64,7 @@ assert.equal(forced.rtaPeakHoldSeconds, 4);
 assert.equal(forced.rtaPeakDecayDbPerSecond, 20);
 assert.equal(forced.rtaPeakResetToken, 9);
 assert.equal(forced.tauFast, 0.125);
-assert.equal(forced.rtwCenters.length, 121);
+assert.equal(forced.rtwCenters.length, 145);
 assert.equal(forced.correlationResponseS, 2.5);
 assert.equal(forced.correlationSilenceThresholdRmsDbfs, -50);
 assert.equal(forced.correlationResetToken, 7);
@@ -99,6 +99,8 @@ assert.equal(selectionContext.applyRtaBpoSelection('1_3'), '1_3');
 assert.equal(selectionContext.CONFIG.RTA_BAR_LAYOUT, 'rtw');
 
 const twelfthCenters = getRtwCenters('1_12');
+assert.equal(twelfthCenters[0], 5);
+assert.equal(twelfthCenters.at(-1), 20000);
 const staleTwelfthPacket = {
   engine: 'iir',
   bpo: '1_12',
diff --git a/src/audio.rs b/src/audio.rs
index cc59036..d8a4667 100644
--- a/src/audio.rs
+++ b/src/audio.rs
@@ -90,24 +90,26 @@ const BOX_MAX_DB: f32 = 9.0;
 const NATIVE_RECORDER_DISCONTINUITY_BLEND_FRAMES: usize = 256;
 #[cfg(target_os = "linux")]
 const RTW_CENTERS_1_6: &[f32] = &[
-    20.0, 22.4, 25.0, 28.0, 31.5, 35.5, 40.0, 45.0, 50.0, 56.0, 63.0, 70.8, 80.0, 90.0, 100.0,
-    112.0, 125.0, 141.0, 160.0, 180.0, 200.0, 224.0, 250.0, 282.0, 315.0, 355.0, 400.0, 450.0,
-    500.0, 560.0, 630.0, 708.0, 800.0, 900.0, 1000.0, 1120.0, 1250.0, 1410.0, 1600.0, 1800.0,
-    2000.0, 2240.0, 2500.0, 2820.0, 3150.0, 3550.0, 4000.0, 4500.0, 5000.0, 5600.0, 6300.0, 7080.0,
-    8000.0, 9000.0, 10000.0, 11200.0, 12500.0, 14100.0, 16000.0, 18000.0, 20000.0,
+    5.0, 5.6, 6.3, 7.08, 8.0, 9.0, 10.0, 11.2, 12.5, 14.1, 16.0, 18.0, 20.0, 22.4, 25.0, 28.0,
+    31.5, 35.5, 40.0, 45.0, 50.0, 56.0, 63.0, 70.8, 80.0, 90.0, 100.0, 112.0, 125.0, 141.0, 160.0,
+    180.0, 200.0, 224.0, 250.0, 282.0, 315.0, 355.0, 400.0, 450.0, 500.0, 560.0, 630.0, 708.0,
+    800.0, 900.0, 1000.0, 1120.0, 1250.0, 1410.0, 1600.0, 1800.0, 2000.0, 2240.0, 2500.0, 2820.0,
+    3150.0, 3550.0, 4000.0, 4500.0, 5000.0, 5600.0, 6300.0, 7080.0, 8000.0, 9000.0, 10000.0,
+    11200.0, 12500.0, 14100.0, 16000.0, 18000.0, 20000.0,
 ];
 #[cfg(target_os = "linux")]
 const RTW_CENTERS_1_12: &[f32] = &[
-    20.0, 21.2, 22.4, 23.8, 25.0, 26.5, 28.0, 29.8, 31.5, 33.4, 35.5, 37.6, 40.0, 42.4, 45.0, 47.5,
-    50.0, 53.0, 56.0, 59.5, 63.0, 67.0, 71.0, 75.0, 80.0, 85.0, 90.0, 95.0, 100.0, 106.0, 112.0,
-    118.0, 125.0, 132.0, 140.0, 150.0, 160.0, 170.0, 180.0, 190.0, 200.0, 212.0, 224.0, 238.0,
-    250.0, 265.0, 280.0, 298.0, 315.0, 334.0, 355.0, 376.0, 400.0, 424.0, 450.0, 475.0, 500.0,
-    530.0, 560.0, 595.0, 630.0, 670.0, 710.0, 750.0, 800.0, 850.0, 900.0, 950.0, 1000.0, 1060.0,
-    1120.0, 1180.0, 1250.0, 1320.0, 1400.0, 1500.0, 1600.0, 1700.0, 1800.0, 1900.0, 2000.0, 2120.0,
-    2240.0, 2380.0, 2500.0, 2650.0, 2800.0, 2980.0, 3150.0, 3340.0, 3550.0, 3760.0, 4000.0, 4240.0,
-    4500.0, 4750.0, 5000.0, 5300.0, 5600.0, 5950.0, 6300.0, 6700.0, 7100.0, 7500.0, 8000.0, 8500.0,
-    9000.0, 9500.0, 10_000.0, 10_600.0, 11_200.0, 11_800.0, 12_500.0, 13_200.0, 14_000.0, 15_000.0,
-    16_000.0, 17_000.0, 18_000.0, 19_000.0, 20_000.0,
+    5.0, 5.3, 5.6, 5.95, 6.3, 6.7, 7.1, 7.5, 8.0, 8.5, 9.0, 9.5, 10.0, 10.6, 11.2, 11.8, 12.5,
+    13.2, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 20.0, 21.2, 22.4, 23.8, 25.0, 26.5, 28.0, 29.8, 31.5,
+    33.4, 35.5, 37.6, 40.0, 42.4, 45.0, 47.5, 50.0, 53.0, 56.0, 59.5, 63.0, 67.0, 71.0, 75.0, 80.0,
+    85.0, 90.0, 95.0, 100.0, 106.0, 112.0, 118.0, 125.0, 132.0, 140.0, 150.0, 160.0, 170.0, 180.0,
+    190.0, 200.0, 212.0, 224.0, 238.0, 250.0, 265.0, 280.0, 298.0, 315.0, 334.0, 355.0, 376.0,
+    400.0, 424.0, 450.0, 475.0, 500.0, 530.0, 560.0, 595.0, 630.0, 670.0, 710.0, 750.0, 800.0,
+    850.0, 900.0, 950.0, 1000.0, 1060.0, 1120.0, 1180.0, 1250.0, 1320.0, 1400.0, 1500.0, 1600.0,
+    1700.0, 1800.0, 1900.0, 2000.0, 2120.0, 2240.0, 2380.0, 2500.0, 2650.0, 2800.0, 2980.0, 3150.0,
+    3340.0, 3550.0, 3760.0, 4000.0, 4240.0, 4500.0, 4750.0, 5000.0, 5300.0, 5600.0, 5950.0, 6300.0,
+    6700.0, 7100.0, 7500.0, 8000.0, 8500.0, 9000.0, 9500.0, 10_000.0, 10_600.0, 11_200.0, 11_800.0,
+    12_500.0, 13_200.0, 14_000.0, 15_000.0, 16_000.0, 17_000.0, 18_000.0, 19_000.0, 20_000.0,
 ];
 
 #[derive(Clone)]
diff --git a/src/rta.rs b/src/rta.rs
index 6fe012a..07e74b3 100644
--- a/src/rta.rs
+++ b/src/rta.rs
@@ -6,9 +6,9 @@
 use std::collections::VecDeque;
 
 pub const RTW_THIRD_OCTAVE_CENTERS: &[f32] = &[
-    20.0, 25.0, 31.5, 40.0, 50.0, 63.0, 80.0, 100.0, 125.0, 160.0, 200.0, 250.0, 315.0, 400.0,
-    500.0, 630.0, 800.0, 1_000.0, 1_250.0, 1_600.0, 2_000.0, 2_500.0, 3_150.0, 4_000.0, 5_000.0,
-    6_300.0, 8_000.0, 10_000.0, 12_500.0, 16_000.0, 20_000.0,
+    5.0, 6.3, 8.0, 10.0, 12.5, 16.0, 20.0, 25.0, 31.5, 40.0, 50.0, 63.0, 80.0, 100.0, 125.0, 160.0,
+    200.0, 250.0, 315.0, 400.0, 500.0, 630.0, 800.0, 1_000.0, 1_250.0, 1_600.0, 2_000.0, 2_500.0,
+    3_150.0, 4_000.0, 5_000.0, 6_300.0, 8_000.0, 10_000.0, 12_500.0, 16_000.0, 20_000.0,
 ];
 
 /// Maps a rounded preferred label to its exact IEC base-ten center frequency.
@@ -448,7 +448,7 @@ mod tests {
 
     #[test]
     fn third_octave_butterworth_has_correct_center_and_edges() {
-        assert_eq!(RTW_THIRD_OCTAVE_CENTERS.len(), 31);
+        assert_eq!(RTW_THIRD_OCTAVE_CENTERS.len(), 37);
         for &nominal_center in RTW_THIRD_OCTAVE_CENTERS {
             let center = exact_fractional_octave_center(nominal_center, 3);
             let (lower, upper) = fractional_octave_edges(center, 3);
diff --git a/src/state.rs b/src/state.rs
index 4087a3f..5e00487 100644
--- a/src/state.rs
+++ b/src/state.rs
@@ -426,7 +426,6 @@ fn normalize_rta_config(mut config: PhoenixRtaConfig) -> PhoenixRtaConfig {
     if config.layout == "rtw" {
         config.engine = "iir".to_string();
         config.order = 6;
-        config.freq_range = "norm".to_string();
     }
 
     // Fast and Slow are named standard responses, not free tuning controls.
@@ -853,7 +852,7 @@ mod tests {
         assert_eq!(config.filterbank, "legacy");
         assert_eq!(config.bpo, "1_12");
         assert_eq!(config.order, 6);
-        assert_eq!(config.freq_range, "norm");
+        assert_eq!(config.freq_range, "lf");
     }
 
     #[test]
diff --git a/www/core/audio.js b/www/core/audio.js
index 8d1e0fc..45dd0a8 100644
--- a/www/core/audio.js
+++ b/www/core/audio.js
@@ -927,7 +927,7 @@ export function buildRtaRuntimeConfig(CONFIG = {}) {
     lrFractionalDelayEnabled: !!CONFIG.LR_FRACTIONAL_DELAY_ENABLED,
     lrFractionalDelaySamples: Number.isFinite(CONFIG.LR_FRACTIONAL_DELAY_SAMPLES) ? CONFIG.LR_FRACTIONAL_DELAY_SAMPLES : 0,
     bpo: runtimeBpoMode,
-    freqRange: rtwProfile ? 'norm' : (CONFIG.RTA_FREQ_RANGE || 'norm'),
+    freqRange: CONFIG.RTA_FREQ_RANGE === 'lf' ? 'lf' : 'norm',
     weighting: CONFIG.RTA_WEIGHTING || 'z',
     order: rtwProfile ? 6 : (CONFIG.RTA_IIR_ORDER || 6),
     tauFast: CONFIG.RTA_IIR_TAU_FAST || 0.125,
diff --git a/www/core/config.js b/www/core/config.js
index 7a9743a..8b7b312 100644
--- a/www/core/config.js
+++ b/www/core/config.js
@@ -821,7 +821,6 @@ function loadConfig(opts = {}) {
     if (CONFIG.RTA_BAR_LAYOUT === 'rtw') {
       CONFIG.RTA_ENGINE = 'iir';
       CONFIG.RTA_IIR_ORDER = 6;
-      CONFIG.RTA_FREQ_RANGE = 'norm';
       const hold = Number(CONFIG.RTA_PEAK_HOLD_SEC);
       CONFIG.RTA_PEAK_HOLD_SEC = hold >= 3.25 ? 4.0 : 2.5;
     }
@@ -1168,7 +1167,6 @@ function applyPhoenixGlobalConfig(payload = {}) {
   if (CONFIG.RTA_BAR_LAYOUT === 'rtw') {
     CONFIG.RTA_ENGINE = 'iir';
     CONFIG.RTA_IIR_ORDER = 6;
-    CONFIG.RTA_FREQ_RANGE = 'norm';
   }
   const spectroGamma = Number(payload.spectroGamma);
   if (Number.isFinite(spectroGamma)) CONFIG.SPECTRO_GAMMA = Math.max(0.3, Math.min(1.2, spectroGamma));
diff --git a/www/core/rtw_centers.js b/www/core/rtw_centers.js
index 753fef8..3723107 100644
--- a/www/core/rtw_centers.js
+++ b/www/core/rtw_centers.js
@@ -1,10 +1,11 @@
 export const RTW_CENTER_MAP = {
   '1_3': [
-    20, 25, 31.5, 40, 50, 63, 80, 100, 125, 160,
+    5, 6.3, 8, 10, 12.5, 16, 20, 25, 31.5, 40, 50, 63, 80, 100, 125, 160,
     200, 250, 315, 400, 500, 630, 800, 1000, 1250, 1600,
     2000, 2500, 3150, 4000, 5000, 6300, 8000, 10000, 12500, 16000, 20000,
   ],
   '1_6': [
+    5, 5.6, 6.3, 7.08, 8, 9, 10, 11.2, 12.5, 14.1, 16, 18,
     20, 22.4, 25, 28, 31.5, 35.5, 40, 45, 50, 56,
     63, 70.8, 80, 90, 100, 112, 125, 141, 160, 180,
     200, 224, 250, 282, 315, 355, 400, 450, 500, 560,
@@ -13,6 +14,8 @@ export const RTW_CENTER_MAP = {
     6300, 7080, 8000, 9000, 10000, 11200, 12500, 14100, 16000, 18000, 20000,
   ],
   '1_12': [
+    5, 5.3, 5.6, 5.95, 6.3, 6.7, 7.1, 7.5, 8, 8.5, 9, 9.5,
+    10, 10.6, 11.2, 11.8, 12.5, 13.2, 14, 15, 16, 17, 18, 19,
     20, 21.2, 22.4, 23.8, 25, 26.5, 28, 29.8, 31.5, 33.4,
     35.5, 37.6, 40, 42.4, 45, 47.5, 50, 53, 56, 59.5,
     63, 67, 71, 75, 80, 85, 90, 95, 100, 106,
diff --git a/www/ui/options.js b/www/ui/options.js
index 1312690..ebdaba3 100644
--- a/www/ui/options.js
+++ b/www/ui/options.js
@@ -1002,7 +1002,7 @@ function wireHandlers(env) {
     return val;
   });
   h('opt_rtaFreq', v => {
-    CONFIG.RTA_FREQ_RANGE = CONFIG.RTA_BAR_LAYOUT === 'rtw' ? 'norm' : ((v === 'lf') ? 'lf' : 'norm');
+    CONFIG.RTA_FREQ_RANGE = (v === 'lf') ? 'lf' : 'norm';
     return CONFIG.RTA_FREQ_RANGE;
   });
   h('opt_rtaDisplayGainFft', v => { CONFIG.RTA_DISPLAY_GAIN_FFT_DB = clamp(+v, -25, 25); }, 'val_rtaDisplayGainFft', v=>`${v} dB`);
@@ -1013,11 +1013,9 @@ function wireHandlers(env) {
     if (val === 'rtw') {
       CONFIG.RTA_ENGINE = 'iir';
       CONFIG.RTA_IIR_ORDER = 6;
-      CONFIG.RTA_FREQ_RANGE = 'norm';
       const forced = {
         opt_rtaEngine: 'iir',
         opt_rtaOrder: '6',
-        opt_rtaFreq: 'norm',
       };
       for (const [id, value] of Object.entries(forced)) {
         const control = document.getElementById(id);
diff --git a/www/views/realtime.js b/www/views/realtime.js
index 46c2adb..d499a23 100644
--- a/www/views/realtime.js
+++ b/www/views/realtime.js
@@ -11,7 +11,7 @@ const METER_PAD_BOTTOM = 5;
 const METER_SLOT_SHRINK = 24; // reduziert nutzbare Höhe leicht, damit Slot niedriger wirkt
 const METER_EXTRA_BOTTOM_PAD = 5;
 const FLOOR_DB = -120;
-const RTA_X_TICKS = [20, 31.5, 63, 125, 250, 500, 1000, 2000, 4000, 8000, 16000];
+const RTA_X_TICKS = [5, 10, 20, 31.5, 63, 125, 250, 500, 1000, 2000, 4000, 8000, 16000];
 const DEFAULT_RTA_BAR_BASE_COLOR = MID_COLOR;
 const RTA_PEAK_COLOR = WARN_COLOR;
 const EMBEDDED_RTA_HIDE_20HZ_WIDTH = 420;