diff --git a/CMakeLists.txt b/CMakeLists.txt
index 88ecb47..5a85b6d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -57,9 +57,12 @@ qt_add_executable(metabolus
     src/synth/Synth.cpp
     src/synth/Synth.h
     resources/resources.qrc
-    src/ui/widgets/SmartSlider.cpp
-    src/ui/widgets/SmartSlider.h
-    src/ui/widgets/SmartSlider.ui
+    src/ui/widgets/SmartSlider/SmartSlider.cpp
+    src/ui/widgets/SmartSlider/SmartSlider.h
+    src/ui/widgets/SmartSlider/SmartSlider.ui
+    src/ui/widgets/EnvelopeGenerator/EnvelopeGenerator.cpp
+    src/ui/widgets/EnvelopeGenerator/EnvelopeGenerator.h
+    src/ui/widgets/EnvelopeGenerator/EnvelopeGenerator.ui
 )
 
 set_target_properties(metabolus PROPERTIES AUTOUIC ON)
diff --git a/src/ui/MainWindow.cpp b/src/ui/MainWindow.cpp
index b5e3328..2cea975 100644
--- a/src/ui/MainWindow.cpp
+++ b/src/ui/MainWindow.cpp
@@ -2,7 +2,7 @@
 #include "MainWindow.h"
 #include "ui_MainWindow.h"
 
-#include "SmartSlider.h"
+#include "SmartSlider/SmartSlider.h"
 #include "../ParameterStore.h"
 
 MainWindow::MainWindow(QWidget *parent) :
@@ -11,41 +11,38 @@ MainWindow::MainWindow(QWidget *parent) :
     audio_(new AudioEngine()),
     keyboard_(audio_->noteQueue()) {
 
+    // Initialize UI
     ui_->setupUi(this);
     setFocusPolicy(Qt::StrongFocus);
 
-    // Initialize UI
-
     // Connect buttons to slots
     connect(ui_->buttonReset, &QPushButton::clicked, this, &MainWindow::onResetClicked);
 
     // synth business
     audio_->start();
 
-    // slider business
-    connect(ui_->sliderGainA, &SmartSlider::valueChanged, this, [this](float v) {
-        audio_->parameters()->set(ParamId::Osc1VolumeEnvA, v); // bind valueChanged signal to the ParameterStore
-    });
-    connect(ui_->sliderGainD, &SmartSlider::valueChanged, this, [this](float v) {
-        audio_->parameters()->set(ParamId::Osc1VolumeEnvD, v); // bind valueChanged signal to the ParameterStore
-    });
-    connect(ui_->sliderGainS, &SmartSlider::valueChanged, this, [this](float v) {
-        audio_->parameters()->set(ParamId::Osc1VolumeEnvS, v); // bind valueChanged signal to the ParameterStore
-    });
-    connect(ui_->sliderGainR, &SmartSlider::valueChanged, this, [this](float v) {
-        audio_->parameters()->set(ParamId::Osc1VolumeEnvR, v); // bind valueChanged signal to the ParameterStore
-    });
+    connect(ui_->envelopeOsc1Volume, &EnvelopeGenerator::envelopeChanged,
+        this, [this](float a, float d, float s, float r) {
+            audio_->parameters()->set(ParamId::Osc1VolumeEnvA, a);
+            audio_->parameters()->set(ParamId::Osc1VolumeEnvD, d);
+            audio_->parameters()->set(ParamId::Osc1VolumeEnvS, s);
+            audio_->parameters()->set(ParamId::Osc1VolumeEnvR, r);
+            // TODO: parameters()->setEnv(ENV_ID, a, d, s ,r)
+        });
+
     // initialize to defaults
-    ui_->sliderGainA->setRange(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvA)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvA)].max);
-    ui_->sliderGainA->setValue(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvA)].def);
-    ui_->sliderGainD->setRange(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvD)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvD)].max);
-    ui_->sliderGainD->setValue(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvD)].def);
-    ui_->sliderGainS->setRange(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvS)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvS)].max);
-    ui_->sliderGainS->setValue(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvS)].def);
-    ui_->sliderGainR->setRange(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvR)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvR)].max);
-    ui_->sliderGainR->setValue(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvR)].def);
-    // TODO: package a smartSlider into an envelope controller widget
-    // then intialization and parameter bindings can be done from the envelope controller
+    ui_->envelopeOsc1Volume->setRanges(
+        PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvA)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvA)].max,
+        PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvD)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvD)].max,
+        PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvS)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvS)].max,
+        PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvR)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvR)].max
+    );
+    ui_->envelopeOsc1Volume->setAttack(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvA)].def);
+    ui_->envelopeOsc1Volume->setDecay(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvD)].def);
+    ui_->envelopeOsc1Volume->setSustain(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvS)].def);
+    ui_->envelopeOsc1Volume->setRelease(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvR)].def);
+
+    // TODO: assign envelope widget a ParamID so that intialization and parameter bindings can be done from the envelope controller
 }
 
 MainWindow::~MainWindow() {
@@ -63,12 +60,14 @@ void MainWindow::keyReleaseEvent(QKeyEvent* event) {
 void MainWindow::onResetClicked() {
 
     // initialize to defaults
-    ui_->sliderGainA->setRange(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvA)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvA)].max);
-    ui_->sliderGainA->setValue(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvA)].def);
-    ui_->sliderGainD->setRange(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvD)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvD)].max);
-    ui_->sliderGainD->setValue(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvD)].def);
-    ui_->sliderGainS->setRange(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvS)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvS)].max);
-    ui_->sliderGainS->setValue(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvS)].def);
-    ui_->sliderGainR->setRange(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvR)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvR)].max);
-    ui_->sliderGainR->setValue(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvR)].def);
+    ui_->envelopeOsc1Volume->setRanges(
+        PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvA)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvA)].max,
+        PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvD)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvD)].max,
+        PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvS)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvS)].max,
+        PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvR)].min, PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvR)].max
+    );
+    ui_->envelopeOsc1Volume->setAttack(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvA)].def);
+    ui_->envelopeOsc1Volume->setDecay(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvD)].def);
+    ui_->envelopeOsc1Volume->setSustain(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvS)].def);
+    ui_->envelopeOsc1Volume->setRelease(PARAM_DEFS[static_cast<size_t>(ParamId::Osc1VolumeEnvR)].def);
 }
diff --git a/src/ui/MainWindow.ui b/src/ui/MainWindow.ui
index 75e7a27..4faadb0 100644
--- a/src/ui/MainWindow.ui
+++ b/src/ui/MainWindow.ui
@@ -6,8 +6,8 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>739</width>
-    <height>605</height>
+    <width>800</width>
+    <height>600</height>
    </rect>
   </property>
   <property name="windowTitle">
@@ -35,53 +35,17 @@
      <string>Reset</string>
     </property>
    </widget>
-   <widget class="SmartSlider" name="sliderGainR" native="true">
+   <widget class="EnvelopeGenerator" name="envelopeOsc1Volume" native="true">
     <property name="geometry">
      <rect>
-      <x>480</x>
-      <y>180</y>
-      <width>120</width>
-      <height>300</height>
+      <x>150</x>
+      <y>130</y>
+      <width>500</width>
+      <height>360</height>
      </rect>
     </property>
-    <property name="autoFillBackground">
-     <bool>true</bool>
-    </property>
-   </widget>
-   <widget class="SmartSlider" name="sliderGainA" native="true">
-    <property name="geometry">
-     <rect>
-      <x>120</x>
-      <y>180</y>
-      <width>120</width>
-      <height>300</height>
-     </rect>
-    </property>
-    <property name="autoFillBackground">
-     <bool>true</bool>
-    </property>
-   </widget>
-   <widget class="SmartSlider" name="sliderGainD" native="true">
-    <property name="geometry">
-     <rect>
-      <x>240</x>
-      <y>180</y>
-      <width>120</width>
-      <height>300</height>
-     </rect>
-    </property>
-    <property name="autoFillBackground">
-     <bool>true</bool>
-    </property>
-   </widget>
-   <widget class="SmartSlider" name="sliderGainS" native="true">
-    <property name="geometry">
-     <rect>
-      <x>360</x>
-      <y>180</y>
-      <width>120</width>
-      <height>300</height>
-     </rect>
+    <property name="acceptDrops">
+     <bool>false</bool>
     </property>
     <property name="autoFillBackground">
      <bool>true</bool>
@@ -91,9 +55,9 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>SmartSlider</class>
+   <class>EnvelopeGenerator</class>
    <extends>QWidget</extends>
-   <header>SmartSlider.h</header>
+   <header>EnvelopeGenerator/EnvelopeGenerator.h</header>
    <container>1</container>
   </customwidget>
  </customwidgets>
diff --git a/src/ui/widgets/EnvelopeGenerator/EnvelopeGenerator.cpp b/src/ui/widgets/EnvelopeGenerator/EnvelopeGenerator.cpp
new file mode 100644
index 0000000..4ace9c1
--- /dev/null
+++ b/src/ui/widgets/EnvelopeGenerator/EnvelopeGenerator.cpp
@@ -0,0 +1,73 @@
+
+#include "EnvelopeGenerator.h"
+#include "ui_EnvelopeGenerator.h"
+
+#include <iostream>
+
+EnvelopeGenerator::EnvelopeGenerator(QWidget* parent) : QWidget(parent), ui_(new Ui::EnvelopeGenerator) {
+
+    ui_->setupUi(this);
+
+    auto connectSlider = [this](SmartSlider* s) {
+        connect(s, &SmartSlider::valueChanged,
+                this, &EnvelopeGenerator::emitEnvelope);
+    };
+
+    connectSlider(ui_->sliderAttack);
+    connectSlider(ui_->sliderDecay);
+    connectSlider(ui_->sliderSustain);
+    connectSlider(ui_->sliderRelease);
+}
+
+EnvelopeGenerator::~EnvelopeGenerator() {
+    delete ui_;
+}
+
+// getters are here to separate ui from header
+float EnvelopeGenerator::attack() const {
+    return ui_->sliderAttack->value();
+}
+
+float EnvelopeGenerator::decay() const {
+    return ui_->sliderDecay->value();
+}
+
+float EnvelopeGenerator::sustain() const {
+    return ui_->sliderSustain->value();
+}
+
+float EnvelopeGenerator::release() const {
+    return ui_->sliderRelease->value();
+}
+
+void EnvelopeGenerator::setAttack(float v) {
+    ui_->sliderAttack->setValue(v);
+}
+
+void EnvelopeGenerator::setDecay(float v) {
+    ui_->sliderDecay->setValue(v);
+}
+
+void EnvelopeGenerator::setSustain(float v) {
+    ui_->sliderSustain->setValue(v);
+}
+
+void EnvelopeGenerator::setRelease(float v) {
+    ui_->sliderRelease->setValue(v);
+}
+
+void EnvelopeGenerator::setRanges(float minA, float maxA, float minD, float maxD, float minS, float maxS, float minR, float maxR) {
+    ui_->sliderAttack->setRange(minA, maxA);
+    ui_->sliderDecay->setRange(minD, maxD);
+    ui_->sliderSustain->setRange(minS, maxS);
+    ui_->sliderRelease->setRange(minR, maxR);
+}
+
+void EnvelopeGenerator::emitEnvelope() {
+    emit envelopeChanged(
+        attack(),
+        decay(),
+        sustain(),
+        release()
+    );
+}
\ No newline at end of file
diff --git a/src/ui/widgets/EnvelopeGenerator/EnvelopeGenerator.h b/src/ui/widgets/EnvelopeGenerator/EnvelopeGenerator.h
new file mode 100644
index 0000000..573e13e
--- /dev/null
+++ b/src/ui/widgets/EnvelopeGenerator/EnvelopeGenerator.h
@@ -0,0 +1,37 @@
+
+#pragma once
+
+#include <QWidget>
+
+QT_BEGIN_NAMESPACE
+namespace Ui { class EnvelopeGenerator; }
+QT_END_NAMESPACE
+
+// this is for the widget, not the synth object named Envelope
+class EnvelopeGenerator : public QWidget {
+    Q_OBJECT
+public:
+    explicit EnvelopeGenerator(QWidget* parent = nullptr);
+    ~EnvelopeGenerator();
+
+    void setAttack(float v);
+    void setDecay(float v);
+    void setSustain(float v);
+    void setRelease(float v);
+
+    void setRanges(float minA, float maxA, float minD, float maxD, float minS, float maxS, float minR, float maxR);
+
+    float attack() const;
+    float decay() const;
+    float sustain() const;
+    float release() const;
+
+signals:
+    void envelopeChanged(double a, double d, double s, double r);
+
+private:
+
+    Ui::EnvelopeGenerator* ui_;
+
+    void emitEnvelope();
+};
diff --git a/src/ui/widgets/EnvelopeGenerator/EnvelopeGenerator.ui b/src/ui/widgets/EnvelopeGenerator/EnvelopeGenerator.ui
new file mode 100644
index 0000000..6511e09
--- /dev/null
+++ b/src/ui/widgets/EnvelopeGenerator/EnvelopeGenerator.ui
@@ -0,0 +1,195 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>EnvelopeGenerator</class>
+ <widget class="QWidget" name="EnvelopeGenerator">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>500</width>
+    <height>360</height>
+   </rect>
+  </property>
+  <property name="sizePolicy">
+   <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
+    <horstretch>0</horstretch>
+    <verstretch>0</verstretch>
+   </sizepolicy>
+  </property>
+  <property name="windowTitle">
+   <string>Form</string>
+  </property>
+  <widget class="SmartSlider" name="sliderDecay" native="true">
+   <property name="geometry">
+    <rect>
+     <x>130</x>
+     <y>50</y>
+     <width>120</width>
+     <height>300</height>
+    </rect>
+   </property>
+   <property name="autoFillBackground">
+    <bool>true</bool>
+   </property>
+  </widget>
+  <widget class="SmartSlider" name="sliderRelease" native="true">
+   <property name="geometry">
+    <rect>
+     <x>370</x>
+     <y>50</y>
+     <width>120</width>
+     <height>300</height>
+    </rect>
+   </property>
+   <property name="autoFillBackground">
+    <bool>true</bool>
+   </property>
+  </widget>
+  <widget class="SmartSlider" name="sliderSustain" native="true">
+   <property name="geometry">
+    <rect>
+     <x>250</x>
+     <y>50</y>
+     <width>120</width>
+     <height>300</height>
+    </rect>
+   </property>
+   <property name="autoFillBackground">
+    <bool>true</bool>
+   </property>
+  </widget>
+  <widget class="SmartSlider" name="sliderAttack" native="true">
+   <property name="geometry">
+    <rect>
+     <x>10</x>
+     <y>50</y>
+     <width>120</width>
+     <height>300</height>
+    </rect>
+   </property>
+   <property name="autoFillBackground">
+    <bool>true</bool>
+   </property>
+  </widget>
+  <widget class="Line" name="line">
+   <property name="geometry">
+    <rect>
+     <x>0</x>
+     <y>340</y>
+     <width>491</width>
+     <height>20</height>
+    </rect>
+   </property>
+   <property name="orientation">
+    <enum>Qt::Orientation::Horizontal</enum>
+   </property>
+  </widget>
+  <widget class="Line" name="line_2">
+   <property name="geometry">
+    <rect>
+     <x>0</x>
+     <y>30</y>
+     <width>491</width>
+     <height>20</height>
+    </rect>
+   </property>
+   <property name="orientation">
+    <enum>Qt::Orientation::Horizontal</enum>
+   </property>
+  </widget>
+  <widget class="QLabel" name="label">
+   <property name="geometry">
+    <rect>
+     <x>50</x>
+     <y>0</y>
+     <width>21</width>
+     <height>31</height>
+    </rect>
+   </property>
+   <property name="font">
+    <font>
+     <pointsize>20</pointsize>
+    </font>
+   </property>
+   <property name="text">
+    <string>A</string>
+   </property>
+   <property name="alignment">
+    <set>Qt::AlignmentFlag::AlignCenter</set>
+   </property>
+  </widget>
+  <widget class="QLabel" name="label_2">
+   <property name="geometry">
+    <rect>
+     <x>170</x>
+     <y>0</y>
+     <width>30</width>
+     <height>31</height>
+    </rect>
+   </property>
+   <property name="font">
+    <font>
+     <pointsize>20</pointsize>
+    </font>
+   </property>
+   <property name="text">
+    <string>D</string>
+   </property>
+   <property name="alignment">
+    <set>Qt::AlignmentFlag::AlignCenter</set>
+   </property>
+  </widget>
+  <widget class="QLabel" name="label_3">
+   <property name="geometry">
+    <rect>
+     <x>300</x>
+     <y>0</y>
+     <width>20</width>
+     <height>31</height>
+    </rect>
+   </property>
+   <property name="font">
+    <font>
+     <pointsize>20</pointsize>
+    </font>
+   </property>
+   <property name="text">
+    <string>S</string>
+   </property>
+   <property name="alignment">
+    <set>Qt::AlignmentFlag::AlignCenter</set>
+   </property>
+  </widget>
+  <widget class="QLabel" name="label_4">
+   <property name="geometry">
+    <rect>
+     <x>420</x>
+     <y>0</y>
+     <width>20</width>
+     <height>31</height>
+    </rect>
+   </property>
+   <property name="font">
+    <font>
+     <pointsize>20</pointsize>
+    </font>
+   </property>
+   <property name="text">
+    <string>R</string>
+   </property>
+   <property name="alignment">
+    <set>Qt::AlignmentFlag::AlignCenter</set>
+   </property>
+  </widget>
+ </widget>
+ <customwidgets>
+  <customwidget>
+   <class>SmartSlider</class>
+   <extends>QWidget</extends>
+   <header>SmartSlider/SmartSlider.h</header>
+   <container>1</container>
+  </customwidget>
+ </customwidgets>
+ <resources/>
+ <connections/>
+</ui>
diff --git a/src/ui/widgets/SmartSlider.cpp b/src/ui/widgets/SmartSlider/SmartSlider.cpp
similarity index 97%
rename from src/ui/widgets/SmartSlider.cpp
rename to src/ui/widgets/SmartSlider/SmartSlider.cpp
index 7fd0e33..db20c5b 100644
--- a/src/ui/widgets/SmartSlider.cpp
+++ b/src/ui/widgets/SmartSlider/SmartSlider.cpp
@@ -57,6 +57,10 @@ void SmartSlider::setValue(float value) {
     emit valueChanged(value);
 }
 
+float SmartSlider::value() {
+    return ui_->spinValue->value();
+}
+
 void SmartSlider::onSliderChanged(int32_t v) {
     float min = ui_->spinMin->value();
     float max = ui_->spinMax->value();
diff --git a/src/ui/widgets/SmartSlider.h b/src/ui/widgets/SmartSlider/SmartSlider.h
similarity index 96%
rename from src/ui/widgets/SmartSlider.h
rename to src/ui/widgets/SmartSlider/SmartSlider.h
index cf49f87..5ef8f38 100644
--- a/src/ui/widgets/SmartSlider.h
+++ b/src/ui/widgets/SmartSlider/SmartSlider.h
@@ -19,6 +19,9 @@ public:
     void setRange(float min, float max);
     void setValue(float value);
 
+    // getters
+    float value();
+
 signals:
     void valueChanged(float value);
 
diff --git a/src/ui/widgets/SmartSlider.ui b/src/ui/widgets/SmartSlider/SmartSlider.ui
similarity index 100%
rename from src/ui/widgets/SmartSlider.ui
rename to src/ui/widgets/SmartSlider/SmartSlider.ui