diff --git a/CLAUDE.md b/CLAUDE.md
index 4814c9a..f2bb376 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -1,39 +1,48 @@
-Bitphase is a chiptune tracker for creating music on retro sound chips. Built with Svelte 5, TypeScript, Vite, and Tailwind 4.
+# CLAUDE.md
 
-## Architecture
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
 
-### Directory Structure
+## Overview
 
-- `src/lib/chips/` - Chip implementations (currently AY-8910). Each chip has: `schema.ts` (channel/field definitions), `adapter.ts` (data manipulation), `renderer.ts` (pattern display), `types.ts`
-- `src/lib/models/` - Domain models: `project.ts`, `song.ts`, `project-fields.ts`
-- `src/lib/services/` - Business logic: `audio/`, `file/` (import/export), `pattern/` (editing, navigation, clipboard), `project/`, `modal/`
-- `src/lib/stores/` - Reactive state using `.svelte.ts` files with `$state` rune
-- `src/lib/ui-rendering/` - Canvas-based renderers for pattern editor and order list
-- `src/lib/components/` - UI components organized by feature (Menu, Song, Tables, Instruments, Modal, etc.)
-- `src/lib/config/` - App configuration (menu definitions, settings)
-- `tests/` - Test files mirroring src structure
+Bitphase is a chiptune tracker for creating music on retro sound chips. Built with Svelte 5, TypeScript, Vite, and Tailwind 4. Currently supports AY-3-8910/YM2149F chip, with architecture designed for future chip support.
 
-### Key Patterns
+## Commands
 
-- **Chip abstraction**: Never hardcode chip-specific features. Use `src/lib/chips/base/schema.ts` for generic definitions. Chips implement adapters and renderers extending base classes.
-- **State management**: Use Svelte 5 runes (`$state`, `$derived`, `$effect`) in `.svelte.ts` files. Do not use writable stores.
-- **Pattern editing**: Field-based editing system in `src/lib/services/pattern/editing/` with strategies per field type.
+- `pnpm dev` — Start dev server (builds WASM first)
+- `pnpm build` — Production build
+- `pnpm check` — TypeScript and Svelte type checking (run this to catch lint errors)
+- `pnpm test` — Run tests in watch mode (vitest)
+- `pnpm test:run` — Run tests once
+- `pnpm vitest run tests/path/to/file.test.ts` — Run a single test file
+- `pnpm build:wasm` — Rebuild WASM only (requires Emscripten SDK with `emcc` in PATH)
 
-### External Dependencies
+## Architecture
 
-- `external/ayumi/` - AY-8910 emulator C code, compiled to WASM via Emscripten
-- WASM output goes to `public/ayumi.wasm`
+### Directory Structure
 
-### Path Alias
+- `src/lib/chips/` — Chip implementations. Each chip has: `schema.ts`, `adapter.ts`, `renderer.ts`, `types.ts`
+  - `base/` — Base interfaces and generic definitions
+  - `ay/` — AY-3-8910 implementation
+- `src/lib/models/` — Domain models: `project.ts`, `song.ts`, `project-fields.ts`
+- `src/lib/services/` — Business logic: `audio/`, `file/` (import/export), `pattern/` (editing, navigation, clipboard), `project/`, `modal/`
+- `src/lib/stores/` — Reactive state using `.svelte.ts` files with `$state` rune
+- `src/lib/ui-rendering/` — Canvas-based renderers for pattern editor and order list
+- `src/lib/components/` — UI components organized by feature
+- `src/lib/config/` — App configuration (menu definitions, settings)
+- `tests/` — Test files mirroring `src/` structure
+- `external/ayumi/` — AY-8910 emulator C code, compiled to WASM → `public/ayumi.wasm`
 
-`@` maps to `./src` (configured in vite and vitest)
+### Key Patterns
 
-- Svelte 5 syntax only (runes, `onclick` not `on:click`)
-- No comments in code - write self-documenting code
-- Tailwind 4 for styling
-- Follow KISS, DRY, SOLID principles. Keep very good OOP practices.
-- Tests go in `tests/` directory mirroring `src/` structure
+- **Chip abstraction**: Never hardcode chip-specific features in generic code. Use `src/lib/chips/base/schema.ts` for generic definitions. Chips implement adapters and renderers extending base classes. AY-specific code must stay in `src/lib/chips/ay/`.
+- **State management**: Svelte 5 runes (`$state`, `$derived`, `$effect`) in `.svelte.ts` files. Do not use writable stores.
+- **Pattern editing**: Field-based editing system in `src/lib/services/pattern/editing/` with strategies per field type.
+- **Path alias**: `@` maps to `./src` (configured in both vite and vitest).
 
-Currently bitphase supports only AY-8910/YM2149F chip, but architecture needs to support other chips in the future. Therefore, it is important to keep the code modular and easy to extend. Using AY specific code in generic parts is not allowed, because when we get to the point of adding another chip, we will have to rewrite a lot of code.
+## Code Style
 
-Please never allow lint errors. If you see any, fix them. We had lots of production bugs because of lint errors.
+- Svelte 5 syntax only — runes, `onclick` not `on:click`, `{#snippet}` not slots
+- No comments in code — write self-documenting code
+- Tailwind 4 for styling
+- Follow KISS, DRY, SOLID principles with good OOP practices
+- Never allow lint errors — run `pnpm check` to verify. We had production bugs from lint errors.
diff --git a/README.md b/README.md
index 32575eb..2a2a830 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,54 @@
 
 A modern web-based chiptune tracker designed for creating music on retro sound chips. Currently supports the AY-3-8910 / YM2149F chip (used in ZX Spectrum and other 8-bit computers), with plans to support additional chips in the future.
 
+## Changelog
+
+### Pattern Editor Navigation
+- **Ctrl+Left / Ctrl+Right** — Jump between channels
+- **Ctrl+Up / Ctrl+Down** — Jump to first / last row (Home / End)
+
+### Natural Tuning Tables
+- Natural (just intonation) tuning now supports **all 12 root notes** (C through B)
+- Root note selector appears when Natural tuning table is selected
+- Uses just intonation ratios: 1, 16/15, 9/8, 6/5, 5/4, 4/3, 64/45, 3/2, 8/5, 5/3, 16/9, 15/8
+
+### Instrument Editor
+- **Duplicate row** button (copy icon) per row
+- **Add new row** button at the top of the table
+- Row actions always visible: delete, duplicate, delete-below
+
+### Table Editor (Arpeggios)
+- **Duplicate row** button (copy icon) per row
+- **Add new row** button at the top of the table
+
+### Resizable Right Panel
+- Drag the left edge of the right panel to resize
+- Panel width persisted across sessions (localStorage)
+
+### Persistent Settings
+- **Hex mode** toggle persisted across browser sessions (shared between Instruments and Tables views)
+
+### Alpha Mask (Virtual Channel Gating)
+
+Each instrument row has an **alpha** field (0–F), visible as the **α** column in the instrument editor. Alpha controls **virtual channel priority** — it determines which virtual channel gets to play on a shared hardware channel.
+
+**How it works:**
+
+When multiple virtual channels (e.g. A, A', A'') share one hardware channel, alpha on the **primary** (leftmost) channel acts as a gate:
+
+- **Alpha = F (15)**: Fully opaque — primary channel always wins, even if silent. This is the default, so existing songs are unaffected.
+- **Alpha = 0**: Fully transparent — any active underlying channel punches through.
+- **Alpha 1–E**: Threshold gate — an underlying channel wins only if its alpha **exceeds** the primary's alpha.
+- Among qualifying underlying channels, **leftmost** (highest priority) wins.
+- If no underlying channel qualifies, the primary still plays.
+
+**Key detail:** Alpha is the **sole gating mechanism**. A silent primary with alpha=F produces opaque silence (blocks underlying channels). A silent primary with alpha=0 is transparent (lets underlying channels through). Volume and mixer state do not affect priority.
+
+**Gating instrument pattern:**
+Create a looping instrument on the primary channel with volume=0 throughout. Set alpha=F on ticks where you want silence, and alpha=0 on ticks where underlying channels should play. This creates rhythmic punch-through patterns without the primary producing any sound.
+
+Alpha values are stored in `.btp` files and default to 15 for older files and VT2/PT3 imports. Single-channel playback (no virtual channels) is unaffected by alpha.
+
 ## Prerequisites
 
 - **Node.js** (v18 or higher)
diff --git a/public/ay-audio-driver.js b/public/ay-audio-driver.js
index 4df8bf2..7c5ed2d 100644
--- a/public/ay-audio-driver.js
+++ b/public/ay-audio-driver.js
@@ -455,6 +455,7 @@ class AYAudioDriver {
 				this.channelMixerState[channelIndex].noise = false;
 				this.channelMixerState[channelIndex].envelope = false;
 				state.channelEnvelopeEnabled[channelIndex] = false;
+				state.channelCurrentAlpha[channelIndex] = 15;
 				continue;
 			}
 
@@ -470,6 +471,7 @@ class AYAudioDriver {
 				this.channelMixerState[channelIndex].noise = false;
 				this.channelMixerState[channelIndex].envelope = false;
 				state.channelEnvelopeEnabled[channelIndex] = false;
+				state.channelCurrentAlpha[channelIndex] = 15;
 				continue;
 			}
 
@@ -483,6 +485,7 @@ class AYAudioDriver {
 				noiseAdd: 0,
 				envelopeAdd: 0,
 				volume: 15,
+				alpha: 15,
 				amplitudeSliding: false,
 				amplitudeSlideUp: false,
 				toneAccumulation: false,
@@ -501,6 +504,7 @@ class AYAudioDriver {
 				this.channelMixerState[channelIndex].tone = false;
 				this.channelMixerState[channelIndex].noise = false;
 				this.channelMixerState[channelIndex].envelope = false;
+				state.channelCurrentAlpha[channelIndex] = 15;
 				state.instrumentPositions[channelIndex]++;
 				if (state.instrumentPositions[channelIndex] >= effectiveRowsLength) {
 					if (effectiveLoop > 0 && effectiveLoop < effectiveRowsLength) {
@@ -561,6 +565,8 @@ class AYAudioDriver {
 				state.channelInstrumentVolumes[channelIndex] = instrumentRow.volume;
 			}
 
+			state.channelCurrentAlpha[channelIndex] = instrumentRow.alpha ?? 15;
+
 			if (instrumentRow.amplitudeSliding) {
 				if (instrumentRow.amplitudeSlideUp) {
 					if (state.channelAmplitudeSliding[channelIndex] < 15) {
diff --git a/public/ayumi-state.js b/public/ayumi-state.js
index 66db46e..84bf85f 100644
--- a/public/ayumi-state.js
+++ b/public/ayumi-state.js
@@ -11,7 +11,8 @@ const AY_CHANNEL_ARRAY_SPECS = [
 	['channelAmplitudeSliding', 0],
 	['channelEnvelopeEnabled', false],
 	['channelMuted', false],
-	['channelSoundEnabled', false]
+	['channelSoundEnabled', false],
+	['channelCurrentAlpha', 15]
 ];
 
 class AyumiState extends TrackerState {
diff --git a/public/virtual-channel-mixer.js b/public/virtual-channel-mixer.js
index e7f43da..29a5baa 100644
--- a/public/virtual-channel-mixer.js
+++ b/public/virtual-channel-mixer.js
@@ -60,15 +60,24 @@ class VirtualChannelMixer {
 			}
 
 			let selectedVch = -1;
-			for (const vch of virtualIndices) {
-				if (this._isChannelActive(vch, virtualRegisterState, state)) {
-					selectedVch = vch;
-					break;
-				}
-			}
+			const primaryVch = virtualIndices[0];
+			const primaryAlpha = state.channelCurrentAlpha?.[primaryVch] ?? 15;
 
-			if (selectedVch === -1) {
-				selectedVch = virtualIndices[virtualIndices.length - 1];
+			if (primaryAlpha >= 15) {
+				selectedVch = primaryVch;
+			} else {
+				for (let i = 1; i < virtualIndices.length; i++) {
+					const vch = virtualIndices[i];
+					if (!this._isChannelActive(vch, virtualRegisterState, state)) continue;
+					const underlyingAlpha = state.channelCurrentAlpha?.[vch] ?? 15;
+					if (underlyingAlpha > primaryAlpha) {
+						selectedVch = vch;
+						break;
+					}
+				}
+				if (selectedVch === -1) {
+					selectedVch = primaryVch;
+				}
 			}
 
 			this._copyChannel(virtualRegisterState, selectedVch, this.hardwareRegisterState, hwCh);
diff --git a/src/lib/chips/ay/AYInstrumentEditor.svelte b/src/lib/chips/ay/AYInstrumentEditor.svelte
index 4697f0c..47f1c9d 100644
--- a/src/lib/chips/ay/AYInstrumentEditor.svelte
+++ b/src/lib/chips/ay/AYInstrumentEditor.svelte
@@ -3,6 +3,7 @@
 	import IconCarbonTrashCan from '~icons/carbon/trash-can';
 	import IconCarbonDelete from '~icons/carbon/delete';
 	import IconCarbonAdd from '~icons/carbon/add';
+	import IconCarbonCopy from '~icons/carbon/copy';
 	import IconCarbonVolumeUp from '~icons/carbon/volume-up';
 	import IconCarbonArrowsVertical from '~icons/carbon/arrows-vertical';
 	import IconCarbonChartWinLoss from '~icons/carbon/chart-win-loss';
@@ -55,6 +56,7 @@
 		noiseAdd: 0,
 		envelopeAdd: 0,
 		volume: 0,
+		alpha: 15,
 		loop: false,
 		amplitudeSliding: false,
 		amplitudeSlideUp: false,
@@ -162,6 +164,7 @@
 						noiseAdd: 0,
 						envelopeAdd: 0,
 						volume: 15,
+						alpha: 15,
 						loop: false,
 						amplitudeSliding: false,
 						amplitudeSlideUp: false,
@@ -240,7 +243,7 @@
 		const allowedPattern = asHex ? /[^0-9a-fA-F-]/g : /[^0-9-]/g;
 		text = text.replace(/\+/g, '').replace(allowedPattern, '');
 
-		if (field === 'volume') {
+		if (field === 'volume' || field === 'alpha') {
 			if (asHex) {
 				if (text.length > 1) {
 					text = text.substring(0, 1);
@@ -273,7 +276,7 @@
 		}
 
 		if (parsed !== null) {
-			if (field === 'volume') {
+			if (field === 'volume' || field === 'alpha') {
 				parsed = Math.max(0, Math.min(15, parsed));
 			}
 			updateRow(index, field, parsed);
@@ -362,6 +365,13 @@
 		updateArraysAfterRowChange([...rows, { ...EMPTY_ROW }]);
 	}
 
+	function duplicateRow(index: number) {
+		if (rows.length >= MAX_ROWS) return;
+		const newRows = [...rows];
+		newRows.splice(index + 1, 0, { ...rows[index] });
+		updateArraysAfterRowChange(newRows);
+	}
+
 	function setRowCount(targetCount: number) {
 		const count = Math.max(1, Math.min(MAX_ROWS, targetCount));
 		if (count === rows.length) return;
@@ -579,6 +589,15 @@
 						</div>
 					</div>
 				{/if}
+				<div class="flex items-center justify-center py-1">
+					<button
+						class="flex cursor-pointer items-center justify-center rounded p-0.5 text-[var(--color-app-text-muted)] transition-colors hover:bg-[var(--color-app-surface-hover)] hover:text-green-400"
+						onclick={addRow}
+						title="Add new row">
+						<IconCarbonAdd class="mr-1 h-3.5 w-3.5" />
+						<span class="mr-1 text-xs">Add new row</span>
+					</button>
+				</div>
 				<table
 					bind:this={tableRef}
 					class="row-editor-table table-fixed border-collapse bg-[var(--color-app-surface)] font-mono text-xs select-none">
@@ -586,7 +605,7 @@
 						<tr>
 							<th class={isExpanded ? 'w-14 min-w-14 px-2 py-1.5' : 'px-1 py-1'}
 								>row</th>
-							<th class={isExpanded ? 'w-8 px-1.5' : 'w-6 px-0.5'}></th>
+							<th class={isExpanded ? 'w-20 min-w-20 px-1' : 'w-16 min-w-16 px-0.5'}></th>
 							<th
 								class={isExpanded ? 'w-6 px-1.5' : 'w-4 px-0.5'}
 								bind:this={loopColumnRef}>{isExpanded ? 'loop' : 'lp'}</th>
@@ -706,6 +725,13 @@
 										class={isExpanded ? 'h-3.5 w-3.5' : 'h-3 w-3'} />
 								</div>
 							</th>
+							<th
+								class={isExpanded
+									? 'w-14 min-w-14 px-1'
+									: 'w-14 px-0.5 text-[0.65rem]'}
+								title="Alpha (transparency for fill layer)">
+								<span class={isExpanded ? 'text-xs' : 'text-[0.65rem]'}>α</span>
+							</th>
 							<th
 								class={isExpanded
 									? 'w-8 min-w-8 px-1'
@@ -735,6 +761,7 @@
 								<th></th>
 								<th></th>
 								<th></th>
+								<th></th>
 							</tr>
 						{/if}
 					</thead>
@@ -752,8 +779,8 @@
 									class="border border-[var(--color-app-border)] {selected
 										? ROW_SELECTION_STYLES.cell
 										: 'bg-[var(--color-app-surface-secondary)]'} {isExpanded
-										? 'px-1.5'
-										: 'px-0.5'}">
+										? 'w-20 min-w-20 px-1'
+										: 'w-16 min-w-16 px-0.5'}">
 									<div
 										class="flex items-center justify-center {isExpanded
 											? 'gap-1'
@@ -768,6 +795,16 @@
 											<IconCarbonTrashCan
 												class={isExpanded ? 'h-3.5 w-3.5' : 'h-3 w-3'} />
 										</button>
+										<button
+											class="flex cursor-pointer items-center justify-center rounded p-0.5 text-[var(--color-app-text-muted)] transition-colors hover:bg-[var(--color-app-surface-hover)] hover:text-blue-400"
+											onclick={(e) => {
+												e.stopPropagation();
+												duplicateRow(index);
+											}}
+											title="Duplicate this row">
+											<IconCarbonCopy
+												class={isExpanded ? 'h-3.5 w-3.5' : 'h-3 w-3'} />
+										</button>
 										{#if index < rows.length - 1}
 											<button
 												class="flex cursor-pointer items-center justify-center rounded p-0.5 text-[var(--color-app-text-muted)] transition-colors hover:bg-[var(--color-app-surface-hover)] hover:text-red-500"
@@ -775,11 +812,9 @@
 													e.stopPropagation();
 													removeRowsFromBottom(index);
 												}}
-												title="Remove all rows from bottom up to this one">
+												title="Remove all rows below this one">
 												<IconCarbonDelete
-													class={isExpanded
-														? 'h-3.5 w-3.5'
-														: 'h-3 w-3'} />
+													class={isExpanded ? 'h-3.5 w-3.5' : 'h-3 w-3'} />
 											</button>
 										{/if}
 									</div>
@@ -963,6 +998,18 @@
 										onfocus={(e) => (e.target as HTMLInputElement).select()}
 										oninput={(e) => updateNumericField(index, 'volume', e)} />
 								</td>
+								<!-- Alpha -->
+								<td class={isExpanded ? 'w-12 min-w-12 px-1.5' : 'w-12 px-0.5'}>
+									<input
+										type="text"
+										class="w-full min-w-0 overflow-x-auto rounded border border-[var(--color-app-border)] bg-[var(--color-app-surface)] {isExpanded
+											? 'px-2 py-1 text-xs'
+											: 'px-1 py-0.5 text-[0.65rem]'} text-[var(--color-app-text-secondary)] placeholder-[var(--color-app-text-muted)] focus:border-[var(--color-app-primary)] focus:outline-none"
+										value={formatNum(row.alpha ?? 15)}
+										onkeydown={(e) => handleNumericKeyDown(index, e)}
+										onfocus={(e) => (e.target as HTMLInputElement).select()}
+										oninput={(e) => updateNumericField(index, 'alpha', e)} />
+								</td>
 								<!-- Amplitude Slide (merged: off/up/down) -->
 								<td
 									class="w-8 min-w-8 {isExpanded
@@ -992,7 +1039,7 @@
 					</tbody>
 					<tfoot>
 						<tr>
-							<td colspan="16" class="px-2 py-1">
+							<td colspan="17" class="px-2 py-1">
 								<div class="flex items-center justify-center">
 									<button
 										class="flex cursor-pointer items-center justify-center rounded p-0.5 text-[var(--color-app-text-muted)] transition-colors hover:bg-[var(--color-app-surface-hover)] hover:text-green-400"
@@ -1005,7 +1052,7 @@
 							</td>
 						</tr>
 						<tr>
-							<td colspan="16" class="border-t border-[var(--color-app-border)] p-0">
+							<td colspan="17" class="border-t border-[var(--color-app-border)] p-0">
 								<RowResizeHandle
 									rowCount={rows.length}
 									onRowCountChange={setRowCount}
diff --git a/src/lib/chips/ay/schema.ts b/src/lib/chips/ay/schema.ts
index 5e94845..ac106f6 100644
--- a/src/lib/chips/ay/schema.ts
+++ b/src/lib/chips/ay/schema.ts
@@ -1,5 +1,9 @@
 import type { ChipSchema } from '../base/schema';
-import { PT3TuneTables, generate12TETTuningTable } from '../../models/pt3/tuning-tables';
+import {
+	PT3TuneTables,
+	generate12TETTuningTable,
+	generateNaturalTuningTable
+} from '../../models/pt3/tuning-tables';
 
 export const AY_CHIP_SCHEMA: ChipSchema = {
 	chipType: 'ay',
@@ -179,22 +183,50 @@ export const AY_CHIP_SCHEMA: ChipSchema = {
 			group: 'chip',
 			notifyAudioService: true,
 			showWhen: { key: 'tuningTableIndex', value: 5 }
+		},
+		{
+			key: 'naturalRoot',
+			label: 'Root note',
+			type: 'select',
+			options: [
+				{ label: 'C', value: 0 },
+				{ label: 'C#', value: 1 },
+				{ label: 'D', value: 2 },
+				{ label: 'D#', value: 3 },
+				{ label: 'E', value: 4 },
+				{ label: 'F', value: 5 },
+				{ label: 'F#', value: 6 },
+				{ label: 'G', value: 7 },
+				{ label: 'G#', value: 8 },
+				{ label: 'A', value: 9 },
+				{ label: 'A#', value: 10 },
+				{ label: 'B', value: 11 }
+			],
+			defaultValue: 0,
+			group: 'chip',
+			notifyAudioService: true,
+			showWhen: { key: 'tuningTableIndex', value: 4 }
 		}
 	],
 	resolveTuningTable(song) {
 		const index = Number(song.tuningTableIndex ?? 2);
 		const chipFreq = Number(song.chipFrequency ?? 1773400);
 		const a4 = Math.min(880, Math.max(220, Number(song.a4TuningHz ?? 440)));
-		return resolveAYTuningTable(index, chipFreq, a4);
+		const naturalRoot = Number(song.naturalRoot ?? 0);
+		return resolveAYTuningTable(index, chipFreq, a4, naturalRoot);
 	},
-	tuningTableSettingKeys: ['tuningTableIndex', 'a4TuningHz', 'chipFrequency']
+	tuningTableSettingKeys: ['tuningTableIndex', 'a4TuningHz', 'chipFrequency', 'naturalRoot']
 };
 
 export function resolveAYTuningTable(
 	index: number,
 	chipFrequencyHz: number,
-	a4TuningHz: number
+	a4TuningHz: number,
+	naturalRoot: number = 0
 ): number[] {
+	if (index === 4) {
+		return generateNaturalTuningTable(naturalRoot);
+	}
 	if (index >= 0 && index < PT3TuneTables.length) {
 		return [...PT3TuneTables[index]];
 	}
diff --git a/src/lib/components/Instruments/InstrumentsView.svelte b/src/lib/components/Instruments/InstrumentsView.svelte
index ccdfa4c..bf09e71 100644
--- a/src/lib/components/Instruments/InstrumentsView.svelte
+++ b/src/lib/components/Instruments/InstrumentsView.svelte
@@ -64,7 +64,7 @@
 		)
 	);
 
-	let asHex = $state(false);
+	let asHex = $state(localStorage.getItem('instrumentHexMode') === 'true');
 	let selectedInstrumentIndex = $state(0);
 	let instrumentEditorRef: any = $state(null);
 	let selectedInstrumentRowIndices = $state<number[]>([]);
@@ -165,7 +165,7 @@
 		{
 			label: 'Hex',
 			icon: hexIcon,
-			onClick: () => (asHex = !asHex),
+			onClick: () => { asHex = !asHex; localStorage.setItem('instrumentHexMode', String(asHex)); },
 			class: asHex ? 'text-[var(--color-app-primary)]' : ''
 		},
 		{
diff --git a/src/lib/components/Song/SongView.svelte b/src/lib/components/Song/SongView.svelte
index 3760c10..67c147f 100644
--- a/src/lib/components/Song/SongView.svelte
+++ b/src/lib/components/Song/SongView.svelte
@@ -56,6 +56,48 @@
 	let rightPanelActiveTabId = $state('instruments');
 	let isRightPanelExpanded = $state(false);
 	let selectedColumn = $state(0);
+
+	const RIGHT_PANEL_WIDTH_KEY = 'rightPanelWidth';
+	const DEFAULT_PANEL_WIDTH = 512;
+	const MIN_PANEL_WIDTH = 380;
+	const MAX_PANEL_WIDTH = 900;
+	let rightPanelWidth = $state(
+		Math.min(MAX_PANEL_WIDTH, Math.max(MIN_PANEL_WIDTH,
+			parseInt(localStorage.getItem(RIGHT_PANEL_WIDTH_KEY) ?? '', 10) || DEFAULT_PANEL_WIDTH
+		))
+	);
+	let isResizingPanel = $state(false);
+	let panelResizeStartX = $state(0);
+	let panelResizeStartWidth = $state(0);
+
+	function startPanelResize(e: MouseEvent) {
+		isResizingPanel = true;
+		panelResizeStartX = e.clientX;
+		panelResizeStartWidth = rightPanelWidth;
+		e.preventDefault();
+	}
+
+	function onPanelResize(e: MouseEvent) {
+		if (!isResizingPanel) return;
+		const delta = panelResizeStartX - e.clientX;
+		rightPanelWidth = Math.min(MAX_PANEL_WIDTH, Math.max(MIN_PANEL_WIDTH, panelResizeStartWidth + delta));
+	}
+
+	function endPanelResize() {
+		if (!isResizingPanel) return;
+		isResizingPanel = false;
+		localStorage.setItem(RIGHT_PANEL_WIDTH_KEY, String(rightPanelWidth));
+	}
+
+	$effect(() => {
+		if (!isResizingPanel) return;
+		window.addEventListener('mousemove', onPanelResize);
+		window.addEventListener('mouseup', endPanelResize);
+		return () => {
+			window.removeEventListener('mousemove', onPanelResize);
+			window.removeEventListener('mouseup', endPanelResize);
+		};
+	});
 	let selectedFieldKey = $state<string | null>(null);
 
 	$effect(() => {
@@ -555,15 +597,24 @@
 			role="region"
 			aria-label="Instruments and tables"
 			tabindex={0}
-			class="relative z-10 flex h-full shrink-0 flex-col border-l border-[var(--color-app-border)] bg-[var(--color-app-surface-secondary)] outline-none transition-all duration-300 focus:outline-none {isRightPanelExpanded
-				? 'w-[1200px]'
-				: 'w-[32rem]'}"
+			class="relative z-10 flex h-full shrink-0 flex-col border-l border-[var(--color-app-border)] bg-[var(--color-app-surface-secondary)] outline-none focus:outline-none {isRightPanelExpanded
+				? 'w-[1200px] transition-all duration-300'
+				: ''}"
+			style={isRightPanelExpanded ? '' : `width: ${rightPanelWidth}px`}
 			onmousedown={(e: MouseEvent) => {
 				const target = e.target as HTMLElement;
 				if (!target.closest('input, textarea, button, select, [contenteditable="true"], a')) {
 					rightPanelEl?.focus();
 				}
 			}}>
+			{#if !isRightPanelExpanded}
+				<div
+					class="absolute top-0 left-0 z-20 h-full w-1 cursor-col-resize hover:bg-[var(--color-app-primary)]/50 {isResizingPanel ? 'bg-[var(--color-app-primary)]/50' : ''}"
+					onmousedown={startPanelResize}
+					role="button"
+					tabindex="-1"
+					aria-label="Resize panel"></div>
+			{/if}
 			<div class="min-h-0 flex-1 overflow-hidden">
 				<TabView tabs={rightPanelTabs} bind:activeTabId={rightPanelActiveTabId}>
 					{#snippet children(tabId)}
diff --git a/src/lib/components/Tables/TableEditor.svelte b/src/lib/components/Tables/TableEditor.svelte
index 8a05d9f..356903d 100644
--- a/src/lib/components/Tables/TableEditor.svelte
+++ b/src/lib/components/Tables/TableEditor.svelte
@@ -3,6 +3,7 @@
 	import IconCarbonTrashCan from '~icons/carbon/trash-can';
 	import IconCarbonDelete from '~icons/carbon/delete';
 	import IconCarbonAdd from '~icons/carbon/add';
+	import IconCarbonCopy from '~icons/carbon/copy';
 	import Input from '../Input/Input.svelte';
 	import RowResizeHandle from '../RowResizeHandle/RowResizeHandle.svelte';
 	import SelectableRowNumberCell from '../RowEditorTable/SelectableRowNumberCell.svelte';
@@ -233,6 +234,13 @@
 		updateArraysAfterRowChange(rows.slice(0, rowsToKeep));
 	}
 
+	function duplicateRow(index: number) {
+		if (rows.length >= MAX_ROWS) return;
+		const newRows = [...rows];
+		newRows.splice(index + 1, 0, rows[index]);
+		updateArraysAfterRowChange(newRows);
+	}
+
 	function setLoop(index: number) {
 		loopRow = index;
 		updateTable({ loop: loopRow });
@@ -438,6 +446,17 @@
 		<Input class="w-48 text-xs" bind:value={name} />
 	</div>
 
+	<div class="mb-2 ml-2">
+		<button
+			class="flex cursor-pointer items-center gap-1 rounded border border-[var(--color-app-border)] bg-[var(--color-app-surface-secondary)] px-2 py-1 text-xs text-[var(--color-app-text-tertiary)] transition-colors hover:bg-[var(--color-app-surface-hover)] hover:text-green-400 disabled:cursor-not-allowed disabled:opacity-50"
+			onclick={addRow}
+			disabled={rows.length >= MAX_ROWS}
+			title="Add new row">
+			<IconCarbonAdd class="h-3.5 w-3.5" />
+			<span>Add new row</span>
+		</button>
+	</div>
+
 	<div class="flex items-start gap-2 overflow-x-auto">
 		<div class="relative flex flex-col">
 			{#if loopRow >= 0 && loopRow < rows.length && loopColumnRef && tableRef}
@@ -509,6 +528,15 @@
 										title="Remove this row">
 										<IconCarbonTrashCan class="h-3.5 w-3.5" />
 									</button>
+									<button
+										class="flex cursor-pointer items-center justify-center rounded p-0.5 text-[var(--color-app-text-muted)] transition-colors hover:bg-[var(--color-app-surface-hover)] hover:text-blue-400"
+										onclick={(e) => {
+											e.stopPropagation();
+											duplicateRow(index);
+										}}
+										title="Duplicate this row">
+										<IconCarbonCopy class="h-3.5 w-3.5" />
+									</button>
 									{#if index < rows.length - 1}
 										<button
 											class="flex cursor-pointer items-center justify-center rounded p-0.5 text-[var(--color-app-text-muted)] transition-colors hover:bg-[var(--color-app-surface-hover)] hover:text-red-500"
diff --git a/src/lib/components/Tables/TablesView.svelte b/src/lib/components/Tables/TablesView.svelte
index 141d355..1a55c44 100644
--- a/src/lib/components/Tables/TablesView.svelte
+++ b/src/lib/components/Tables/TablesView.svelte
@@ -111,7 +111,7 @@
 		};
 	});
 
-	let asHex = $state(false);
+	let asHex = $state(localStorage.getItem('instrumentHexMode') === 'true');
 	let selectedTableIndex = $state(0);
 	let selectedTableRowIndices = $state<number[]>([]);
 	let tableEditor: TableEditor | null = $state(null);
@@ -332,7 +332,7 @@
 		{
 			label: 'Hex',
 			icon: hexIcon,
-			onClick: () => (asHex = !asHex),
+			onClick: () => { asHex = !asHex; localStorage.setItem('instrumentHexMode', String(asHex)); },
 			class: asHex ? 'text-[var(--color-app-primary)]' : ''
 		},
 		{
diff --git a/src/lib/config/keybindings.ts b/src/lib/config/keybindings.ts
index bf219e3..fc2a72a 100644
--- a/src/lib/config/keybindings.ts
+++ b/src/lib/config/keybindings.ts
@@ -32,6 +32,10 @@ export const ACTION_END = 'end';
 export const ACTION_END_COLUMN = 'end-column';
 export const ACTION_OCTAVE_UP = 'octave-up';
 export const ACTION_OCTAVE_DOWN = 'octave-down';
+export const ACTION_JUMP_CHANNEL_LEFT = 'jump-channel-left';
+export const ACTION_JUMP_CHANNEL_RIGHT = 'jump-channel-right';
+export const ACTION_CURSOR_HOME = 'cursor-home';
+export const ACTION_CURSOR_END = 'cursor-end';
 export const ACTION_SELECT_INSTRUMENT_OR_TABLE_IN_EDITOR = 'select-instrument-or-table-in-editor';
 
 export interface BindableAction {
@@ -99,6 +103,26 @@ export const BINDABLE_ACTIONS: BindableAction[] = [
 		label: 'End (last column)',
 		defaultShortcut: 'Mod+End'
 	},
+	{
+		id: ACTION_JUMP_CHANNEL_LEFT,
+		label: 'Jump to previous channel',
+		defaultShortcut: 'Mod+ArrowLeft'
+	},
+	{
+		id: ACTION_JUMP_CHANNEL_RIGHT,
+		label: 'Jump to next channel',
+		defaultShortcut: 'Mod+ArrowRight'
+	},
+	{
+		id: ACTION_CURSOR_HOME,
+		label: 'Cursor to first row',
+		defaultShortcut: 'Mod+ArrowUp'
+	},
+	{
+		id: ACTION_CURSOR_END,
+		label: 'Cursor to last row',
+		defaultShortcut: 'Mod+ArrowDown'
+	},
 	{
 		id: ACTION_SELECT_INSTRUMENT_OR_TABLE_IN_EDITOR,
 		label: 'Select instrument or table in editor',
diff --git a/src/lib/models/pt3/tuning-tables.ts b/src/lib/models/pt3/tuning-tables.ts
index 777747b..a83d53e 100644
--- a/src/lib/models/pt3/tuning-tables.ts
+++ b/src/lib/models/pt3/tuning-tables.ts
@@ -70,6 +70,28 @@ const TABLE_LENGTH = 96;
 const MIN_PERIOD = 1;
 const MAX_PERIOD = 4095;
 
+const JUST_INTONATION_RATIOS = [
+	1, 16 / 15, 9 / 8, 6 / 5, 5 / 4, 4 / 3, 64 / 45, 3 / 2, 8 / 5, 5 / 3, 16 / 9, 15 / 8
+];
+
+const NATURAL_BASE_PERIOD = 2880;
+
+export function generateNaturalTuningTable(rootSemitone: number): number[] {
+	const result: number[] = [];
+	for (let i = 0; i < TABLE_LENGTH; i++) {
+		const semitone = i % 12;
+		const octave = Math.floor(i / 12);
+		const intervalFromRoot = ((semitone - rootSemitone) % 12 + 12) % 12;
+		const rootRelativeOctave = octave - (semitone < rootSemitone ? 1 : 0);
+		const freqRatio = JUST_INTONATION_RATIOS[intervalFromRoot];
+		let period = Math.round(NATURAL_BASE_PERIOD / freqRatio / Math.pow(2, rootRelativeOctave));
+		if (period > MAX_PERIOD) period = MAX_PERIOD;
+		if (period < MIN_PERIOD) period = MIN_PERIOD;
+		result.push(period);
+	}
+	return result;
+}
+
 export function generate12TETTuningTable(chipFrequencyHz: number, a4Hz: number = 440): number[] {
 	const result: number[] = [];
 	for (let i = 0; i < TABLE_LENGTH; i++) {
diff --git a/src/lib/services/file/file-import.ts b/src/lib/services/file/file-import.ts
index 2a48c35..7fc4e56 100644
--- a/src/lib/services/file/file-import.ts
+++ b/src/lib/services/file/file-import.ts
@@ -200,6 +200,7 @@ function reconstructInstrumentRow(data: any): InstrumentRow {
 		envelopeAdd: data.envelopeAdd ?? 0,
 		envelopeAccumulation: data.envelopeAccumulation ?? false,
 		volume: data.volume ?? 0,
+		alpha: data.alpha ?? 15,
 		loop: data.loop ?? false,
 		amplitudeSliding: data.amplitudeSliding ?? false,
 		amplitudeSlideUp: data.amplitudeSlideUp ?? false,
diff --git a/src/lib/services/file/vt-converter.ts b/src/lib/services/file/vt-converter.ts
index cb82cda..803522f 100644
--- a/src/lib/services/file/vt-converter.ts
+++ b/src/lib/services/file/vt-converter.ts
@@ -147,7 +147,8 @@ class VT2Converter {
 						noiseAccumulation: line.noiseAccumulation || false,
 						envelopeAdd: line.noiseAdd,
 						envelopeAccumulation: line.noiseAccumulation || false,
-						retriggerEnvelope: false
+						retriggerEnvelope: false,
+						alpha: 15
 					});
 				}),
 				loopPoint,
@@ -282,7 +283,8 @@ class VT2Converter {
 						envelopeAccumulation: line.noiseAccumulation || false,
 						toneAccumulation: line.toneAccumulation || false,
 						noiseAccumulation: line.noiseAccumulation || false,
-						retriggerEnvelope: false
+						retriggerEnvelope: false,
+						alpha: 15
 					});
 				}),
 				loopPoint,
@@ -503,7 +505,8 @@ class VT2Converter {
 						envelopeAccumulation: line.noiseAccumulation || false,
 						toneAccumulation: line.toneAccumulation || false,
 						noiseAccumulation: line.noiseAccumulation || false,
-						retriggerEnvelope: false
+						retriggerEnvelope: false,
+						alpha: 15
 					});
 				}),
 				loopPoint,
diff --git a/src/lib/services/pattern/pattern-keyboard-shortcuts.ts b/src/lib/services/pattern/pattern-keyboard-shortcuts.ts
index 422aea0..83b74b9 100644
--- a/src/lib/services/pattern/pattern-keyboard-shortcuts.ts
+++ b/src/lib/services/pattern/pattern-keyboard-shortcuts.ts
@@ -28,7 +28,11 @@ import {
 	ACTION_HOME,
 	ACTION_HOME_COLUMN,
 	ACTION_END,
-	ACTION_END_COLUMN
+	ACTION_END_COLUMN,
+	ACTION_JUMP_CHANNEL_LEFT,
+	ACTION_JUMP_CHANNEL_RIGHT,
+	ACTION_CURSOR_HOME,
+	ACTION_CURSOR_END
 } from '../../config/keybindings';
 
 export interface PatternKeyboardShortcutsContext {
@@ -275,6 +279,44 @@ function dispatchCommandAction(
 			ctx.onSetSelectedColumn(navigationState.selectedColumn);
 			return true;
 		}
+		case ACTION_JUMP_CHANNEL_LEFT: {
+			const navState = PatternNavigationService.moveToPrevChannel(
+				{
+					selectedRow: ctx.selectedRow,
+					currentPatternOrderIndex: ctx.currentPatternOrderIndex,
+					selectedColumn: ctx.selectedColumn
+				},
+				ctx.navigationContext
+			);
+			ctx.onClearSelection();
+			ctx.onSetSelectedColumn(navState.selectedColumn);
+			return true;
+		}
+		case ACTION_JUMP_CHANNEL_RIGHT: {
+			const navState = PatternNavigationService.moveToNextChannel(
+				{
+					selectedRow: ctx.selectedRow,
+					currentPatternOrderIndex: ctx.currentPatternOrderIndex,
+					selectedColumn: ctx.selectedColumn
+				},
+				ctx.navigationContext
+			);
+			ctx.onClearSelection();
+			ctx.onSetSelectedColumn(navState.selectedColumn);
+			return true;
+		}
+		case ACTION_CURSOR_HOME:
+			if (!ctx.isPlaying) {
+				ctx.onClearSelection();
+				ctx.onSetSelectedRow(0);
+			}
+			return true;
+		case ACTION_CURSOR_END:
+			if (!ctx.isPlaying) {
+				ctx.onClearSelection();
+				ctx.onSetSelectedRow(ctx.pattern.length - 1);
+			}
+			return true;
 		default:
 			return false;
 	}
diff --git a/src/lib/services/pattern/pattern-navigation.ts b/src/lib/services/pattern/pattern-navigation.ts
index d603e82..324f1ed 100644
--- a/src/lib/services/pattern/pattern-navigation.ts
+++ b/src/lib/services/pattern/pattern-navigation.ts
@@ -142,6 +142,68 @@ export class PatternNavigationService {
 		};
 	}
 
+	static moveToPrevChannel(state: NavigationState, context: NavigationContext): NavigationState {
+		const { currentPattern, converter, formatter, schema, getCellPositions } = context;
+		const genericPattern = converter.toGeneric(currentPattern);
+		const genericPatternRow = genericPattern.patternRows[state.selectedRow];
+		const genericChannels = genericPattern.channels.map(
+			(ch: GenericChannel) => ch.rows[state.selectedRow]
+		);
+		const rowString = formatter.formatRow(
+			genericPatternRow,
+			genericChannels,
+			state.selectedRow,
+			schema
+		);
+		const cellPositions = getCellPositions(rowString, state.selectedRow);
+		const hasGlobal = !!(schema.globalTemplate && schema.globalFields);
+		const channelCount = genericPattern.channels.length;
+		const totalSlots = (hasGlobal ? 1 : 0) + channelCount;
+		if (totalSlots <= 1) return state;
+
+		const slotForColumn: number[] = [];
+		for (let col = 0; col < cellPositions.length; col++) {
+			const cell = cellPositions[col];
+			if (!cell.fieldKey) {
+				slotForColumn[col] = -1;
+				continue;
+			}
+			const isGlobal = !!schema.globalFields?.[cell.fieldKey];
+			if (isGlobal) {
+				slotForColumn[col] = 0;
+			} else {
+				const channelIndex = PatternTemplateParser.calculateChannelIndexForField(
+					cell.fieldKey,
+					cell.charIndex,
+					rowString,
+					schema
+				);
+				slotForColumn[col] = (hasGlobal ? 1 : 0) + channelIndex;
+			}
+		}
+
+		const firstColumnForSlot: number[] = [];
+		for (let col = 0; col < cellPositions.length; col++) {
+			const slot = slotForColumn[col];
+			if (slot >= 0 && firstColumnForSlot[slot] === undefined) {
+				firstColumnForSlot[slot] = col;
+			}
+		}
+
+		const currentSlot =
+			state.selectedColumn >= 0 && state.selectedColumn < slotForColumn.length
+				? slotForColumn[state.selectedColumn]
+				: 0;
+		const prevSlot = currentSlot > 0 ? currentSlot - 1 : totalSlots - 1;
+		const targetColumn = firstColumnForSlot[prevSlot];
+		if (targetColumn === undefined) return state;
+
+		return {
+			...state,
+			selectedColumn: targetColumn
+		};
+	}
+
 	static moveToNextChannel(state: NavigationState, context: NavigationContext): NavigationState {
 		const { currentPattern, converter, formatter, schema, getCellPositions } = context;
 		const genericPattern = converter.toGeneric(currentPattern);
diff --git a/tests/public/virtual-channel-mixer.test.ts b/tests/public/virtual-channel-mixer.test.ts
index 6ab7052..a8c140e 100644
--- a/tests/public/virtual-channel-mixer.test.ts
+++ b/tests/public/virtual-channel-mixer.test.ts
@@ -4,7 +4,8 @@ import AYChipRegisterState from '../../public/ay-chip-register-state.js';
 
 function createState(channelCount: number) {
 	return {
-		channelSoundEnabled: Array(channelCount).fill(true)
+		channelSoundEnabled: Array(channelCount).fill(true),
+		channelCurrentAlpha: Array(channelCount).fill(15)
 	};
 }
 
@@ -74,7 +75,7 @@ describe('VirtualChannelMixer', () => {
 			expect(result.channels[2].tone).toBe(400);
 		});
 
-		it('should select lower-priority channel when higher-priority is silent', () => {
+		it('should keep silent primary when alpha is F (opaque silence)', () => {
 			mixer.configure({ 1: 2 }, 3);
 			const registerState = new AYChipRegisterState(4);
 			registerState.channels[1].tone = 200;
@@ -86,10 +87,26 @@ describe('VirtualChannelMixer', () => {
 			const state = createState(4);
 			const result = mixer.merge(registerState, state);
 
+			expect(result.channels[1].tone).toBe(200);
+		});
+
+		it('should let underlying through silent primary when alpha is 0 (transparent)', () => {
+			mixer.configure({ 1: 2 }, 3);
+			const registerState = new AYChipRegisterState(4);
+			registerState.channels[1].tone = 200;
+			registerState.channels[1].volume = 0;
+			registerState.channels[2].tone = 300;
+			registerState.channels[2].volume = 8;
+			registerState.channels[3].tone = 400;
+
+			const state = createState(4);
+			state.channelCurrentAlpha[1] = 0;
+			const result = mixer.merge(registerState, state);
+
 			expect(result.channels[1].tone).toBe(300);
 		});
 
-		it('should fall back to last virtual channel when all are inactive', () => {
+		it('should fall back to primary virtual channel when all are inactive', () => {
 			mixer.configure({ 1: 2 }, 3);
 			const registerState = new AYChipRegisterState(4);
 			registerState.channels[1].tone = 200;
@@ -103,7 +120,7 @@ describe('VirtualChannelMixer', () => {
 			state.channelSoundEnabled[2] = false;
 			const result = mixer.merge(registerState, state);
 
-			expect(result.channels[1].tone).toBe(300);
+			expect(result.channels[1].tone).toBe(200);
 		});
 
 		it('should treat envelope volume flag as active', () => {
@@ -136,6 +153,106 @@ describe('VirtualChannelMixer', () => {
 			expect(result.channels[1].mixer.envelope).toBe(true);
 		});
 
+		it('should let underlying channel punch through when primary alpha is 0', () => {
+			mixer.configure({ 0: 2 }, 3);
+			const registerState = new AYChipRegisterState(4);
+			registerState.channels[0].tone = 100;
+			registerState.channels[0].volume = 10;
+			registerState.channels[1].tone = 200;
+			registerState.channels[1].volume = 8;
+
+			const state = createState(4);
+			state.channelCurrentAlpha[0] = 0;
+			state.channelCurrentAlpha[1] = 15;
+			const result = mixer.merge(registerState, state);
+
+			expect(result.channels[0].tone).toBe(200);
+		});
+
+		it('should let underlying win when its alpha exceeds primary alpha', () => {
+			mixer.configure({ 0: 2 }, 3);
+			const registerState = new AYChipRegisterState(4);
+			registerState.channels[0].tone = 100;
+			registerState.channels[0].volume = 10;
+			registerState.channels[1].tone = 200;
+			registerState.channels[1].volume = 8;
+
+			const state = createState(4);
+			state.channelCurrentAlpha[0] = 5;
+			state.channelCurrentAlpha[1] = 10;
+			const result = mixer.merge(registerState, state);
+
+			expect(result.channels[0].tone).toBe(200);
+		});
+
+		it('should keep primary when its alpha equals underlying alpha', () => {
+			mixer.configure({ 0: 2 }, 3);
+			const registerState = new AYChipRegisterState(4);
+			registerState.channels[0].tone = 100;
+			registerState.channels[0].volume = 10;
+			registerState.channels[1].tone = 200;
+			registerState.channels[1].volume = 8;
+
+			const state = createState(4);
+			state.channelCurrentAlpha[0] = 10;
+			state.channelCurrentAlpha[1] = 10;
+			const result = mixer.merge(registerState, state);
+
+			expect(result.channels[0].tone).toBe(100);
+		});
+
+		it('should keep primary with alpha F regardless of underlying', () => {
+			mixer.configure({ 0: 2 }, 3);
+			const registerState = new AYChipRegisterState(4);
+			registerState.channels[0].tone = 100;
+			registerState.channels[0].volume = 10;
+			registerState.channels[1].tone = 200;
+			registerState.channels[1].volume = 8;
+
+			const state = createState(4);
+			state.channelCurrentAlpha[0] = 15;
+			state.channelCurrentAlpha[1] = 15;
+			const result = mixer.merge(registerState, state);
+
+			expect(result.channels[0].tone).toBe(100);
+		});
+
+		it('should skip inactive underlying channels during alpha resolution', () => {
+			mixer.configure({ 0: 3 }, 3);
+			const registerState = new AYChipRegisterState(5);
+			registerState.channels[0].tone = 100;
+			registerState.channels[0].volume = 10;
+			registerState.channels[1].tone = 200;
+			registerState.channels[1].volume = 0;
+			registerState.channels[2].tone = 300;
+			registerState.channels[2].volume = 8;
+
+			const state = createState(5);
+			state.channelCurrentAlpha[0] = 0;
+			state.channelCurrentAlpha[1] = 15;
+			state.channelSoundEnabled[1] = false;
+			state.channelCurrentAlpha[2] = 15;
+			const result = mixer.merge(registerState, state);
+
+			expect(result.channels[0].tone).toBe(300);
+		});
+
+		it('should fall back to primary when underlying alpha does not exceed primary', () => {
+			mixer.configure({ 0: 2 }, 3);
+			const registerState = new AYChipRegisterState(4);
+			registerState.channels[0].tone = 100;
+			registerState.channels[0].volume = 10;
+			registerState.channels[1].tone = 200;
+			registerState.channels[1].volume = 8;
+
+			const state = createState(4);
+			state.channelCurrentAlpha[0] = 10;
+			state.channelCurrentAlpha[1] = 5;
+			const result = mixer.merge(registerState, state);
+
+			expect(result.channels[0].tone).toBe(100);
+		});
+
 		it('should copy global state (envelope, noise)', () => {
 			mixer.configure({ 1: 2 }, 3);
 			const registerState = new AYChipRegisterState(4);