diff --git a/.gitmodules b/.gitmodules
index 84e9e94..1434591 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -4,3 +4,6 @@
 [submodule "implot"]
 	path = implot
 	url = https://github.com/epezent/implot
+[submodule "AudioFFT"]
+	path = AudioFFT
+	url = https://github.com/HiFi-LoFi/AudioFFT
diff --git a/AudioFFT b/AudioFFT
new file mode 160000
index 0000000..0893b53
--- /dev/null
+++ b/AudioFFT
@@ -0,0 +1 @@
+Subproject commit 0893b532dd357c7270609425f5ae9d9b5ae7d725
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 750ad67..d0794b3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -55,9 +55,16 @@
 target_link_libraries(sokol PUBLIC cimgui)
 target_include_directories(sokol INTERFACE sokol)
 
+#=== LIBRARY: AudioFFT
+add_library(audiofft STATIC
+    AudioFFT/AudioFFT.h
+    AudioFFT/AudioFFT.cpp)
+target_include_directories(cimgui INTERFACE AudioFFT)
+
 #=== EXECUTABLE: qb
 set(QB_SOURCES
     launch.c
+    audionode.cpp
     colors.cpp
     colors.hpp
     qb.cpp
@@ -75,8 +82,8 @@
 else()
     add_executable(qb ${QB_SOURCES})
 endif()
-target_include_directories(qb PRIVATE cimgui/imgui implot)
-target_link_libraries(qb sokol)
+target_include_directories(qb PRIVATE cimgui/imgui implot AudioFFT)
+target_link_libraries(qb sokol audiofft)
 
 # explicitly strip dead code
 if (CMAKE_C_COMPILER_ID MATCHES "Clang" AND NOT CMAKE_SYSTEM_NAME STREQUAL Emscripten)
diff --git a/audionode.cpp b/audionode.cpp
new file mode 100644
index 0000000..ea15df4
--- /dev/null
+++ b/audionode.cpp
@@ -0,0 +1,126 @@
+#include "qb.hpp"
+#include "task.hpp"
+#include "AudioFile/AudioFile.h"
+
+namespace qb {
+  audio_node::audio_node(const context *c, const std::string &path)
+    : node(c, path, qb::node_type::audio)
+    , _path(path)
+    , _loadstate(load_state::loading)
+  {
+    taskpool::get().submit_async([this]() { this->load_async(); });
+  }
+
+  const std::vector<float>& audio_node::packed() const {
+    if (!_data || _data->getNumChannels() != 1) {
+      return _packed;
+    }
+    return _data->samples[0];
+  }
+
+  static constexpr double render_rate_hi = 16;
+  static constexpr double render_rate_lo = 4;
+  static constexpr int hires_frame_limit = 1000;
+
+  const std::vector<float>& audio_node::rendered() const {
+    double visframes = 2 * _c->visrad;
+    return visframes > hires_frame_limit ? _rlo : _rhi;
+  }
+
+  double audio_node::rsamplerate() const {
+    double visframes = 2 * _c->visrad;
+    return (visframes > hires_frame_limit ? render_rate_lo : render_rate_hi);
+  }
+
+  void audio_node::load_async() {
+    taskpool::get().submit_frame([this]() {
+        this->_loadstate = load_state(load_state::loading, "loading file");
+      });
+    _data.reset(new audio_file());
+    const bool success = _data->load(_path);
+    if (!success) {
+      taskpool::get().submit_frame([this]() {
+          this->_loadstate = load_state(load_state::failed);
+        });
+      return;
+    }
+
+    taskpool::get().submit_frame([this]() {
+        this->_loadstate =
+          load_state(load_state::loading, "generating hi-res preview");
+      });
+    _rhi = render_samples(render_rate_hi);
+
+    taskpool::get().submit_frame([this]() {
+        this->_loadstate =
+          load_state(load_state::loading, "generating lo-res preview");
+      });
+    _rlo = render_samples(render_rate_lo);
+
+    taskpool::get().submit_frame([this]() {
+        this->_loadstate =
+          load_state(load_state::loading, "packing samples for playback");
+      });
+    if (_data->getNumChannels() != 1) {
+      const size_t channels = _data->getNumChannels();
+      const size_t n = _data->getNumSamplesPerChannel();
+      _packed.reserve(channels * n);
+      for (size_t i = 0; i < n; i++) {
+        for (size_t c = 0; c < channels; c++) {
+          _packed.push_back(_data->samples[c][i]);
+        }
+      }
+    }
+
+    // update load state on main thread: this is what governs whether the UI
+    // accesses the rest of the state here or not.
+    taskpool::get().submit_frame([this]() {
+        this->_loadstate = load_state(load_state::loaded);
+      });
+  }
+
+  std::vector<float> audio_node::render_samples(double framesamples) {
+    const size_t samples = _data->getNumSamplesPerChannel();
+    const double spr =
+      (double)_data->getSampleRate() / (framesamples * _c->framerate());
+    const size_t rsamples = (size_t) ceil((double)samples / spr);
+    const int channels = _data->getNumChannels();
+
+    std::vector<float> rendered;
+    rendered.resize(rsamples);
+    float absmax = 0;
+    for (int i = 0; i < rsamples; i++) {
+      const double s1 = i * spr;
+      const double s2 = (i + 1) * spr;
+      double sum = 0;
+      for (int chan = 0; chan < channels; chan++) {
+        for (size_t s = (size_t)floor(s1);
+             s < (size_t)ceil(s2) && s < _data->samples[chan].size();
+             s++) {
+          double x = _data->samples[chan][s];
+          sum += x;
+        }
+      }
+      const float r = (float) (sum / (spr * channels));
+      absmax = std::max(absmax, fabsf(r));
+      rendered[i] = r;
+    }
+    for (float &f : rendered) {
+      f /= absmax;
+    }
+    return rendered;
+  }
+
+  int audio_node::minframe() const {
+    return 0;
+  }
+
+  int audio_node::maxframe() const {
+    if (_loadstate.stage != load_state::loaded) {
+      return 0;
+    }
+    return (int) ceil(_data->getLengthInSeconds() * _c->framerate());
+  }
+
+  audio_node::~audio_node() = default;
+}
diff --git a/nodeui.cpp b/nodeui.cpp
index 5bcd96d..f61005c 100644
--- a/nodeui.cpp
+++ b/nodeui.cpp
@@ -43,7 +43,7 @@
     const std::vector<float> &r = node->rendered();
 
     const context *c = node->ctx();
-    const int rad = 100;
+    const int rad = 40;
     const double rsamplerate = node->rsamplerate();
     const int64_t s0 = (long) floor(rsamplerate * (c->playhead - c->visrad));
     const int64_t s1 = (long) ceil(rsamplerate * (c->playhead + c->visrad));
diff --git a/qb.cpp b/qb.cpp
index d4b6aa2..e9387e6 100644
--- a/qb.cpp
+++ b/qb.cpp
@@ -2,7 +2,6 @@
 #include "colors.hpp"
 #include "nodeui.hpp"
 #include "task.hpp"
-#include "AudioFile/AudioFile.h"
 
 #include "sokol/sokol_app.h"
 #include "sokol/sokol_audio.h"
@@ -196,126 +195,5 @@
 
   node::node(const context *c, const std::string &n, node_type t)
     : _c(c), _name(n), _type(t) {}
-
-  audio_node::audio_node(const context *c, const std::string &path)
-    : node(c, path, qb::node_type::audio)
-    , _path(path)
-    , _loadstate(load_state::loading)
-  {
-    taskpool::get().submit_async([this]() { this->load_async(); });
-  }
-
-  const std::vector<float>& audio_node::packed() const {
-    if (!_data || _data->getNumChannels() != 1) {
-      return _packed;
-    }
-    return _data->samples[0];
-  }
-
-  static constexpr double render_rate_hi = 8;
-  static constexpr double render_rate_lo = 2;
-  static constexpr int hires_frame_limit = 1000;
-
-  const std::vector<float>& audio_node::rendered() const {
-    double visframes = 2 * _c->visrad;
-    return visframes > hires_frame_limit ? _rlo : _rhi;
-  }
-
-  double audio_node::rsamplerate() const {
-    double visframes = 2 * _c->visrad;
-    return (visframes > hires_frame_limit ? render_rate_lo : render_rate_hi);
-  }
-
-  void audio_node::load_async() {
-    taskpool::get().submit_frame([this]() {
-        this->_loadstate = load_state(load_state::loading, "loading file");
-      });
-    _data.reset(new audio_file());
-    const bool success = _data->load(_path);
-    if (!success) {
-      taskpool::get().submit_frame([this]() {
-          this->_loadstate = load_state(load_state::failed);
-        });
-      return;
-    }
-
-    taskpool::get().submit_frame([this]() {
-        this->_loadstate =
-          load_state(load_state::loading, "generating hi-res preview");
-      });
-    _rhi = render_samples(render_rate_hi);
-
-    taskpool::get().submit_frame([this]() {
-        this->_loadstate =
-          load_state(load_state::loading, "generating lo-res preview");
-      });
-    _rlo = render_samples(render_rate_lo);
-
-    taskpool::get().submit_frame([this]() {
-        this->_loadstate =
-          load_state(load_state::loading, "packing samples for playback");
-      });
-    if (_data->getNumChannels() != 1) {
-      const size_t channels = _data->getNumChannels();
-      const size_t n = _data->getNumSamplesPerChannel();
-      _packed.reserve(channels * n);
-      for (size_t i = 0; i < n; i++) {
-        for (size_t c = 0; c < channels; c++) {
-          _packed.push_back(_data->samples[c][i]);
-        }
-      }
-    }
-
-    // update load state on main thread: this is what governs whether the UI
-    // accesses the rest of the state here or not.
-    taskpool::get().submit_frame([this]() {
-        this->_loadstate = load_state(load_state::loaded);
-      });
-  }
-
-  std::vector<float> audio_node::render_samples(double framesamples) {
-    const size_t samples = _data->getNumSamplesPerChannel();
-    const double spr =
-      (double)_data->getSampleRate() / (framesamples * _c->framerate());
-    const size_t rsamples = (size_t) ceil((double)samples / spr);
-    const int channels = _data->getNumChannels();
-
-    std::vector<float> rendered;
-    rendered.resize(rsamples);
-    float absmax = 0;
-    for (int i = 0; i < rsamples; i++) {
-      const double s1 = i * spr;
-      const double s2 = (i + 1) * spr;
-      double sum = 0;
-      for (int chan = 0; chan < channels; chan++) {
-        for (size_t s = (size_t)floor(s1);
-             s < (size_t)ceil(s2) && s < _data->samples[chan].size();
-             s++) {
-          double x = _data->samples[chan][s];
-          sum += (x < 0 ? -1.0 : 1.0) * sqrt(fabs(x));
-        }
-      }
-      const float r = (float) (sum / (spr * channels));
-      absmax = std::max(absmax, fabsf(r));
-      rendered[i] = r;
-    }
-    for (float &f : rendered) {
-      f /= absmax;
-    }
-    return rendered;
-  }
-
-  int audio_node::minframe() const {
-    return 0;
-  }
-
-  int audio_node::maxframe() const {
-    if (_loadstate.stage != load_state::loaded) {
-      return 0;
-    }
-    return (int) ceil(_data->getLengthInSeconds() * _c->framerate());
-  }
-
-  audio_node::~audio_node() = default;
 }