diff --git a/include/effect_matrix.h b/include/effect_matrix.h
index 8b75c30..5ba9990 100644
--- a/include/effect_matrix.h
+++ b/include/effect_matrix.h
@@ -48,24 +48,40 @@ public:
     RandomMatrixEffectColumn(Window* win, uint8_t dir, bool rnd=false) : MatrixEffectColumn(win, dir, rnd) {};
 };
 
-class MatrixEffect : public Effect {
+class MatrixEffectBase : public Effect {
 protected:
     MatrixEffectColumn** _columns;
+    uint8_t _count;
+    virtual uint8_t _get_count();
+    virtual void _delete();
+    void _init();
+    virtual void _create() = 0;
 public:
     boolean can_be_shown_with_clock();
-    MatrixEffect();
-    virtual ~MatrixEffect();
+    virtual ~MatrixEffectBase();
     void loop(uint16_t ms);
-    String get_name() override { return "matrix"; }
 };
 
-class RainbowMatrixEffect : public MatrixEffect {
+class MatrixEffect : public MatrixEffectBase {
+protected:
+	void _create() override;
+public:
+	MatrixEffect();
+	String get_name() override { return "matrix"; }
+};
+
+class RainbowMatrixEffect : public MatrixEffectBase {
+protected:
+	void _create() override;
 public:
 	RainbowMatrixEffect();
 	String get_name() override { return "rainbow_matrix"; }
 };
 
-class RandomMatrixEffect : public MatrixEffect {
+class RandomMatrixEffect : public MatrixEffectBase {
+protected:
+	uint8_t _get_count() override;
+	void _create() override;
 public:
 	RandomMatrixEffect();
 	String get_name() override { return "random_matrix"; }
diff --git a/include/settings.h b/include/settings.h
index 1bfdf46..f0349d0 100644
--- a/include/settings.h
+++ b/include/settings.h
@@ -28,6 +28,8 @@ struct Settings {
 			uint16_t length_max = 20;
 			uint16_t speed_min = 3;
 			uint16_t speed_max = 7;
+			uint16_t count = 16;
+			uint16_t random_count = 32;
 		} matrix;
 
 		struct /* confetti */ {
diff --git a/src/effect_matrix.cpp b/src/effect_matrix.cpp
index 476f8f5..e602b2d 100644
--- a/src/effect_matrix.cpp
+++ b/src/effect_matrix.cpp
@@ -136,37 +136,61 @@ void RandomMatrixEffectColumn::restart(bool completely_random) {
 
 
 
-boolean MatrixEffect::can_be_shown_with_clock() { return true; };
+boolean MatrixEffectBase::can_be_shown_with_clock() { return true; };
+
+void MatrixEffectBase::_init() {
+	_count = _get_count();
+	_columns = new MatrixEffectColumn* [_count];
+}
+
+uint8_t MatrixEffectBase::_get_count() { return settings.effects.matrix.count; }
 
 MatrixEffect::MatrixEffect() {
-	_columns = new MatrixEffectColumn* [window->width];
-	for (int i=0; i<window->width; i++) _columns[i] = new MatrixEffectColumn(window, MatrixEffectColumn::DIR_SOUTH);
+	_init();
+	_create();
+}
+
+void MatrixEffect::_create() {
+	for (int i=0; i<_count; i++) _columns[i] = new MatrixEffectColumn(window, MatrixEffectColumn::DIR_SOUTH);
 }
 
 RandomMatrixEffect::RandomMatrixEffect() {
-	// No need to initialize _columns, because that will have been done by ctor of MatrixEffect.
-	for (int i=0; i<window->width; i++) {
-		delete _columns[i];
-		_columns[i] = new RandomMatrixEffectColumn(window, random8(4), true);
-	}
+	_init();
+	_create();
 }
 
+void RandomMatrixEffect::_create() {
+	for (int i=0; i<_count; i++) _columns[i] = new RandomMatrixEffectColumn(window, random8(4), true);
+}
+
+uint8_t RandomMatrixEffect::_get_count() { return settings.effects.matrix.random_count; }
+
 RainbowMatrixEffect::RainbowMatrixEffect() {
-	// No need to initialize _columns, because that will have been done by ctor of MatrixEffect.
-	for (int i=0; i<window->width; i++) {
-		delete _columns[i];
-		_columns[i] = new RainbowMatrixEffectColumn(window, MatrixEffectColumn::DIR_SOUTH);
-	}
+	_init();
+	_create();
 }
 
-MatrixEffect::~MatrixEffect() {
-    for (int i=0; i<window->width; i++) {
+void RainbowMatrixEffect::_create() {
+	for (int i=0; i<_count; i++) _columns[i] = new RainbowMatrixEffectColumn(window, MatrixEffectColumn::DIR_SOUTH);
+}
+
+MatrixEffectBase::~MatrixEffectBase() {
+	_delete();
+}
+
+void MatrixEffectBase::_delete() {
+    for (int i=0; i<_count; i++) {
         delete _columns[i];
     }
 	delete[] _columns;
 }
 
-void MatrixEffect::loop(uint16_t ms) {
+void MatrixEffectBase::loop(uint16_t ms) {
+	if (_count != _get_count()) {
+		_delete();
+		_init();
+		_create();
+	}
     window->clear();
-    for (int i=0; i<window->width; i++) _columns[i]->loop(ms);
+    for (int i=0; i<_count; i++) _columns[i]->loop(ms);
 }
diff --git a/src/settings.cpp b/src/settings.cpp
index 2c0dc24..93134ec 100644
--- a/src/settings.cpp
+++ b/src/settings.cpp
@@ -37,6 +37,8 @@ Setting all_settings[] = {
 	{"effects.matrix.length_max", &settings.effects.matrix.length_max, TYPE_UINT8},
 	{"effects.matrix.speed_min", &settings.effects.matrix.speed_min, TYPE_UINT8},
 	{"effects.matrix.speed_max", &settings.effects.matrix.speed_max, TYPE_UINT8},
+	{"effects.matrix.count", &settings.effects.matrix.count, TYPE_UINT8},
+	{"effects.matrix.random_count", &settings.effects.matrix.random_count, TYPE_UINT8},
 
 	{"effects.sines.count", &settings.effects.sines.count, TYPE_UINT8},
 
@@ -45,7 +47,7 @@ Setting all_settings[] = {
 	{"effects.tv_static.black_bar_speed", &settings.effects.tv_static.black_bar_speed, TYPE_UINT16},
 };
 
-const uint8_t all_settings_size = 26;
+const uint8_t all_settings_size = 28;
 
 bool change_setting(const char* key, uint16_t new_value) {
 	LOGln("Settings * Setting %s to new value %d.", key, new_value);