From 539e63f4af5c1f7fdcbb88793a6afb0331a8b48f Mon Sep 17 00:00:00 2001
From: Blitblank <pmcgeee03@gmail.com>
Date: Sat, 3 Jan 2026 19:18:51 -0600
Subject: [PATCH] small tweaks (second stage filter

---
 src/KeyboardController.cpp |  1 +
 src/synth/Synth.cpp        | 14 +++++++++-----
 src/synth/Synth.h          |  4 ++--
 3 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/src/KeyboardController.cpp b/src/KeyboardController.cpp
index 60e0926..5319d24 100644
--- a/src/KeyboardController.cpp
+++ b/src/KeyboardController.cpp
@@ -7,6 +7,7 @@ KeyboardController::KeyboardController(NoteQueue& queue) : queue_(queue) {
 
     // TODO: also configurable via a yml
     keymap_ = {
+        { Qt::Key_Shift, 47 }, // B 2
         { Qt::Key_Z, 48 }, // C 3
         { Qt::Key_S, 49 }, // C#
         { Qt::Key_X, 50 }, // D
diff --git a/src/synth/Synth.cpp b/src/synth/Synth.cpp
index f4febfe..77e3d74 100644
--- a/src/synth/Synth.cpp
+++ b/src/synth/Synth.cpp
@@ -9,7 +9,7 @@
 #endif
 
 // TODO: you get it, also in a yml config
-#define SYNTH_PITCH_STANDARD 440.0f // frequency of home pitch
+#define SYNTH_PITCH_STANDARD 432.0f // frequency of home pitch
 #define SYNTH_MIDI_HOME 69 // midi note index of home pitch
 #define SYNTH_NOTES_PER_OCTAVE 12
 
@@ -25,7 +25,8 @@ void Synth::updateParams() {
 
 void Synth::setSampleRate(uint32_t sampleRate) { 
     sampleRate_ = sampleRate;
-    filter_.setSampleRate(static_cast<float>(sampleRate));
+    filter1_.setSampleRate(static_cast<float>(sampleRate));
+    filter2_.setSampleRate(static_cast<float>(sampleRate));
 }
 
 inline float Synth::getParam(ParamId id) {
@@ -104,7 +105,7 @@ void Synth::process(float* out, uint32_t nFrames, uint32_t sampleRate) {
         }
         
         // TODO: make pitchOffset variable for each oscillator (maybe three values like octave, semitone offset, and pitch offset in cents)
-        float pitchOffset = 1.0f;
+        float pitchOffset = 0.5f;
         float phaseInc = pitchOffset * 2.0f * M_PI * frequency_ / static_cast<float>(sampleRate);
 
         float gain = gainEnv * getParam(ParamId::Osc1VolumeDepth);
@@ -136,8 +137,11 @@ void Synth::process(float* out, uint32_t nFrames, uint32_t sampleRate) {
 
         // filter sample
         float cutoffFreq = cutoffEnv * pow(2.0f, getParam(ParamId::FilterCutoffDepth)) * frequency_;
-        filter_.setParams(Filter::Type::BiquadLowpass, cutoffFreq, resonanceEnv * getParam(ParamId::FilterResonanceDepth));
-        sampleOut = filter_.biquadProcess(sampleOut);
+        filter1_.setParams(Filter::Type::BiquadLowpass, cutoffFreq, resonanceEnv * getParam(ParamId::FilterResonanceDepth));
+        filter2_.setParams(Filter::Type::BiquadLowpass, cutoffFreq, resonanceEnv * getParam(ParamId::FilterResonanceDepth));
+        float filterSample = filter1_.biquadProcess(sampleOut);
+        filterSample = filter2_.biquadProcess(filterSample);
+        sampleOut = filterSample;
 
         // write to buffer
         out[2*i] = sampleOut; // left
diff --git a/src/synth/Synth.h b/src/synth/Synth.h
index 5d14b24..136c64b 100644
--- a/src/synth/Synth.h
+++ b/src/synth/Synth.h
@@ -70,7 +70,7 @@ private:
     Envelope cutoffEnvelope_;
     Envelope resonanceEnvelope_;
 
-    // filters, just one for now
-    Filter filter_;
+    Filter filter1_;
+    Filter filter2_;
 
 };