Various changes

1 year ago · d7b13aad99
parent b933f936f8
commit d7b13aad99
17 changed files with 228 additions and 125 deletions
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@ -3,6 +3,13 @@ project(synth)

 set(CMAKE_CXX_STANDARD 20)
 set(BUILD_SHARED_LIBS OFF)
+if(MSVC)
+    set(CMAKE_CXX_FLAGS_DEBUG "/W4 /DEBUG:FASTLINK /fp:fast")
+    set(CMAKE_CXX_FLAGS_RELEASE "/W4 /O2 /fp:fast /DNDEBUG")
+else()
+    set(CMAKE_CXX_FLAGS_DEBUG "-Wall -g -ffast-math")
+    set(CMAKE_CXX_FLAGS_RELEASE "-Wall -Ofast -DNDEBUG")
+endif()

 if(WIN32)
    option(PA_USE_ASIO "" ON)
@ -26,6 +33,8 @@ add_executable(main
    src/synth/channel.cpp
    src/synth/preset.cpp
    src/synth/voice.cpp
+    src/synth/dsp/notelut.cpp
+    src/synth/dsp/centlut.cpp
    src/synth/dsp/oscillator.cpp
    src/synth/dsp/filter.cpp
    src/synth/dsp/filterlut.cpp
@ -35,12 +44,6 @@ target_include_directories(main PRIVATE include)
 add_executable(genluts src/genluts.cpp)
 target_include_directories(genluts PRIVATE include)

-if(MSVC)
-    target_compile_options(main PRIVATE /fp:fast)
-else()
-    target_compile_options(main PRIVATE -ffast-math)
-endif()
-
 #target_compile_options(main PRIVATE -fsanitize=thread)
 #target_link_options(main PRIVATE -fsanitize=thread)

--- a/include/synth/channel.h
+++ b/include/synth/channel.h
@ -8,6 +8,7 @@
 #include "voicemanager.h"
 #include "voice.h"
 #include "preset.h"
+#include "frame.h"

 class Channel {
 public:
--- a/include/synth/dsp/filter.h
+++ b/include/synth/dsp/filter.h
@ -5,27 +5,34 @@

 #include <cmath>
 #include <cfloat>
+#include <iostream>

+#include "../globals.h"
 #include "util.h"

 #define FILTER_K_BASE 6.214608098422192

-#define KLUT_SIZE 64
-extern float klut[KLUT_SIZE];
-
-inline float freqToK(float x) {
-    float intPart;
-    float fracPart = modf(x * (KLUT_SIZE - 1), &intPart);
-    int index = (int) intPart;
-    if(fracPart < FLT_EPSILON) {
-        return klut[index];
-    } else {
-        return (1 - fracPart) * klut[index] + fracPart * klut[index + 1];
+#ifdef USE_LUTS
+
+    #define K_LUT_SIZE 64
+    
+    extern float kLUT[K_LUT_SIZE];
+
+    inline float freqToK(float x) {
+        float intPart, fracPart = modf(x * (K_LUT_SIZE - 1), &intPart);
+        int index = (int) intPart;
+        return fracPart < FLT_EPSILON ? kLUT[index] : (1 - fracPart) * kLUT[index] + fracPart * kLUT[index + 1];
    }
-    return klut[(int) roundf((KLUT_SIZE - 1) * x)];
-}

-inline float noteToK(float note) {
+#else
+
+    inline float freqToK(float x) {
+        return tan(M_PI_4 * 0.002 * exp(x * FILTER_K_BASE));
+    }
+
+#endif
+
+inline float noteToFltFreq(float note) {
    return ((note - 69) / 12.0) / (FILTER_K_BASE * M_LOG2E);
 }

--- a/include/synth/dsp/util.h
+++ b/include/synth/dsp/util.h
@ -2,19 +2,36 @@
 #define __UTIL_H__

 #include <cmath>
+#include <cfloat>
+
+#include "../globals.h"

 #define PIx2 (2 * M_PI)

-inline float clamp(float x, float a, float b) {
-    return fminf(b, fmaxf(a, x));
-}
+#ifdef USE_LUTS

-inline float dBToGain(float dB) {
-    return pow(10, dB / 20.0);
-}
+    #define NOTE_LUT_SIZE 128
+    #define CENT_LUT_SIZE 128
+
+    extern float noteLUT[NOTE_LUT_SIZE];
+    extern float centLUT[CENT_LUT_SIZE];
+
+    inline float noteToFreq(float note) {
+        float intPart, fracPart = modf(note, &intPart);
+        int index = (int) intPart;
+        return fracPart < FLT_EPSILON ? noteLUT[index] : noteLUT[index] * centLUT[(int) (fracPart * 127.0)];
+    }
+
+#else
+
+    inline float noteToFreq(float note) {
+        return 440 * pow(2, (note - 69) / 12.0);
+    }

-inline float noteToFreq(float note) {
-    return 440 * pow(2, (note - 69) / 12.0);
+#endif
+
+inline float clamp(float x, float a, float b) {
+    return fminf(b, fmaxf(a, x));
 }

 inline float triangle(float phase) {
--- a/include/synth/frame.h
+++ b/include/synth/frame.h
@ -0,0 +1,41 @@
+#ifndef __FRAME_H__
+#define __FRAME_H__
+
+struct frame {
+    float left;
+    float right;
+
+    inline frame operator+(const frame& rhs) {
+        return {
+            .left = left + rhs.left,
+            .right = right + rhs.right
+        };
+    }
+    
+    inline frame operator+=(const frame& rhs) {
+        this->left += rhs.left;
+        this->right += rhs.right;
+        return *this;
+    }
+
+    inline frame operator*(float rhs) {
+        return {
+            .left = left * rhs,
+            .right = right * rhs
+        };
+    }
+
+    inline frame operator+=(float rhs) {
+        this->left += rhs;
+        this->right += rhs;
+        return *this;
+    }
+
+    inline frame operator*=(float rhs) {
+        this->left *= rhs;
+        this->right *= rhs;
+        return *this;
+    }
+};
+
+#endif
--- a/include/synth/globals.h
+++ b/include/synth/globals.h
@ -1,44 +1,8 @@
 #ifndef __GLOBALS_H__
 #define __GLOBALS_H__

-#define SAMPLE_RATE 48000
+#define SAMPLE_RATE 44100

-struct frame {
-    float left;
-    float right;
-
-    inline frame operator+(const frame& rhs) {
-        return {
-            .left = left + rhs.left,
-            .right = right + rhs.right
-        };
-    }
-    
-    inline frame operator+=(const frame& rhs) {
-        this->left += rhs.left;
-        this->right += rhs.right;
-        return *this;
-    }
-
-    inline frame operator*(float rhs) {
-        return {
-            .left = left * rhs,
-            .right = right * rhs
-        };
-    }
-
-    inline frame operator+=(float rhs) {
-        this->left += rhs;
-        this->right += rhs;
-        return *this;
-    }
-
-
-    inline frame operator*=(float rhs) {
-        this->left *= rhs;
-        this->right *= rhs;
-        return *this;
-    }
-};
+//#define USE_LUTS

 #endif
--- a/include/synth/synth.h
+++ b/include/synth/synth.h
@ -3,6 +3,7 @@

 #include "voicemanager.h"
 #include "channel.h"
+#include "frame.h"

 class Synth {
 public:
--- a/include/synth/voice.h
+++ b/include/synth/voice.h
@ -53,7 +53,7 @@ public:
        float out = 0;
        out += (1 - settings->oscMix) * osc1.tick(osc1PhaseStep);
        out +=      settings->oscMix  * osc2.tick(osc2PhaseStep);
-        const float keyTrackVal = settings->keyTrack * noteToK(note);
+        const float keyTrackVal = settings->keyTrack * noteToFltFreq(note);
        out = filter.tick(out, settings->modEnvFltGain * adsrMod.tick() + keyTrackVal + fltFreqAdd);
        out *= adsrAmp.tick();
        return out;
--- a/src/genluts.cpp
+++ b/src/genluts.cpp
@ -1,30 +1,46 @@
-#include <stdio.h>
-#include <math.h>
+#include <cstdio>
+#include <cmath>

-#include "synth/dsp/filter.h"
-
-int main(int argc, char** argv) {
-    FILE* f;
+#define USE_LUTS

-    float klut[KLUT_SIZE];
-    for(int i = 0; i < KLUT_SIZE; ++i) {
-        klut[i] = tan(M_PI_4 * 0.002 * exp(i / (KLUT_SIZE - 1.0) * FILTER_K_BASE));
-    }
+#include "synth/dsp/filter.h"
+#include "synth/dsp/util.h"

-    f = fopen("src/synth/dsp/filterlut.cpp", "w");
-    fputs("float klut[] = {\n", f);
-    for(int i = 0; i < KLUT_SIZE; ++i) {
-        if(i % 16 == 0) {
+void dumpLUT(const char * filename, const char * identifier, float *lut, size_t size) {
+    FILE * f = fopen(filename, "w");
+    fprintf(f, "float %s[] = {\n", identifier);
+    for(int i = 0; i < size; ++i) {
+        if(i % 8 == 0) {
            fputs("    ", f);
        }
-        fprintf(f, "%.7f", klut[i]);
-        if(i < KLUT_SIZE - 1) {
+        fprintf(f, "%13.7f", lut[i]);
+        if(i < size - 1) {
            fputs(", ", f);
        }
-        if(i % 16 == 15) {
+        if(i % 8 == 7) {
            putc('\n', f);
        }
    }
    fputs("};\n", f);
-    fclose(f);    
+    fclose(f);
+}
+
+int main(int argc, char** argv) {
+    float kLUT[K_LUT_SIZE];
+    for(int i = 0; i < K_LUT_SIZE; ++i) {
+        kLUT[i] = tan(M_PI_4 * 0.002 * exp(i / (K_LUT_SIZE - 1.0) * FILTER_K_BASE));
+    }
+    dumpLUT("src/synth/dsp/filterlut.cpp", "kLUT", kLUT, K_LUT_SIZE);
+
+    float noteLUT[NOTE_LUT_SIZE];
+    for(int i = 0; i < NOTE_LUT_SIZE; ++i) {
+        noteLUT[i] = 440 * pow(2, (i - 69) / 12.0);
+    }
+    dumpLUT("src/synth/dsp/notelut.cpp", "noteLUT", noteLUT, NOTE_LUT_SIZE);
+
+    float centLUT[CENT_LUT_SIZE];
+    for(int i = 0; i < CENT_LUT_SIZE; ++i) {
+        centLUT[i] = pow(2, (float) i / ((CENT_LUT_SIZE - 1) * 12.0));
+    }
+    dumpLUT("src/synth/dsp/centlut.cpp", "centLUT", centLUT, CENT_LUT_SIZE);
 }
--- a/src/synth/channel.cpp
+++ b/src/synth/channel.cpp
@ -93,7 +93,6 @@ void Channel::control(int code, int value) {

        case CC_FLT_Q: // Timbre / Harmonic Content (Standard MIDI)
            settings.filter.res = value / 31.75;
-            std::cout << "Q=" << settings.filter.res << std::endl;
            break;

        case CC_AMP_REL: // Release Time (Standard MIDI)
--- a/src/synth/dsp/centlut.cpp
+++ b/src/synth/dsp/centlut.cpp
@ -0,0 +1,18 @@
+float centLUT[] = {
+        1.0000000,     1.0004549,     1.0009100,     1.0013654,     1.0018209,     1.0022767,     1.0027326,     1.0031888, 
+        1.0036452,     1.0041018,     1.0045586,     1.0050156,     1.0054728,     1.0059302,     1.0063878,     1.0068456, 
+        1.0073037,     1.0077620,     1.0082204,     1.0086790,     1.0091379,     1.0095969,     1.0100563,     1.0105158, 
+        1.0109755,     1.0114354,     1.0118955,     1.0123559,     1.0128164,     1.0132772,     1.0137382,     1.0141994, 
+        1.0146607,     1.0151223,     1.0155841,     1.0160462,     1.0165083,     1.0169708,     1.0174334,     1.0178963, 
+        1.0183593,     1.0188227,     1.0192862,     1.0197498,     1.0202137,     1.0206778,     1.0211421,     1.0216067, 
+        1.0220715,     1.0225364,     1.0230016,     1.0234669,     1.0239326,     1.0243984,     1.0248644,     1.0253307, 
+        1.0257971,     1.0262637,     1.0267307,     1.0271977,     1.0276650,     1.0281326,     1.0286002,     1.0290682, 
+        1.0295364,     1.0300047,     1.0304732,     1.0309421,     1.0314111,     1.0318803,     1.0323497,     1.0328194, 
+        1.0332892,     1.0337592,     1.0342295,     1.0347000,     1.0351708,     1.0356417,     1.0361128,     1.0365841, 
+        1.0370557,     1.0375276,     1.0379995,     1.0384717,     1.0389441,     1.0394168,     1.0398897,     1.0403627, 
+        1.0408360,     1.0413095,     1.0417832,     1.0422572,     1.0427313,     1.0432056,     1.0436803,     1.0441550, 
+        1.0446301,     1.0451053,     1.0455807,     1.0460564,     1.0465323,     1.0470084,     1.0474846,     1.0479612, 
+        1.0484380,     1.0489149,     1.0493921,     1.0498694,     1.0503471,     1.0508249,     1.0513029,     1.0517812, 
+        1.0522597,     1.0527384,     1.0532173,     1.0536964,     1.0541759,     1.0546554,     1.0551351,     1.0556152, 
+        1.0560954,     1.0565759,     1.0570565,     1.0575374,     1.0580184,     1.0584998,     1.0589813,     1.0594631
+};
--- a/src/synth/dsp/filterlut.cpp
+++ b/src/synth/dsp/filterlut.cpp
@ -1,6 +1,10 @@
-float klut[] = {
-    0.0015708, 0.0017336, 0.0019134, 0.0021118, 0.0023307, 0.0025723, 0.0028390, 0.0031333, 0.0034582, 0.0038167, 0.0042124, 0.0046491, 0.0051311, 0.0056631, 0.0062502, 0.0068982, 
-    0.0076134, 0.0084028, 0.0092740, 0.0102355, 0.0112968, 0.0124681, 0.0137608, 0.0151877, 0.0167625, 0.0185007, 0.0204193, 0.0225369, 0.0248743, 0.0274544, 0.0303024, 0.0334462, 
-    0.0369167, 0.0407480, 0.0449779, 0.0496483, 0.0548053, 0.0605004, 0.0667905, 0.0737388, 0.0814158, 0.0898997, 0.0992782, 0.1096492, 0.1211226, 0.1338222, 0.1478880, 0.1634790, 
-    0.1807770, 0.1999912, 0.2213640, 0.2451794, 0.2717728, 0.3015462, 0.3349871, 0.3726965, 0.4154281, 0.4641461, 0.5201120, 0.5850177, 0.6611994, 0.7519926, 0.8623521, 1.0000000
+float kLUT[] = {
+        0.0015708,     0.0017336,     0.0019134,     0.0021118,     0.0023307,     0.0025723,     0.0028390,     0.0031333, 
+        0.0034582,     0.0038167,     0.0042124,     0.0046491,     0.0051311,     0.0056631,     0.0062502,     0.0068982, 
+        0.0076134,     0.0084028,     0.0092740,     0.0102355,     0.0112968,     0.0124681,     0.0137608,     0.0151877, 
+        0.0167625,     0.0185007,     0.0204193,     0.0225369,     0.0248743,     0.0274544,     0.0303024,     0.0334462, 
+        0.0369167,     0.0407480,     0.0449779,     0.0496483,     0.0548053,     0.0605004,     0.0667905,     0.0737388, 
+        0.0814158,     0.0898997,     0.0992782,     0.1096492,     0.1211226,     0.1338222,     0.1478880,     0.1634790, 
+        0.1807770,     0.1999912,     0.2213640,     0.2451794,     0.2717728,     0.3015462,     0.3349871,     0.3726965, 
+        0.4154281,     0.4641461,     0.5201120,     0.5850177,     0.6611994,     0.7519926,     0.8623521,     1.0000000
 };
--- a/src/synth/dsp/notelut.cpp
+++ b/src/synth/dsp/notelut.cpp
@ -0,0 +1,18 @@
+float noteLUT[] = {
+        8.1757994,     8.6619568,     9.1770239,     9.7227182,    10.3008614,    10.9133825,    11.5623255,    12.2498569, 
+       12.9782715,    13.7500000,    14.5676174,    15.4338531,    16.3515987,    17.3239136,    18.3540478,    19.4454365, 
+       20.6017227,    21.8267651,    23.1246510,    24.4997139,    25.9565430,    27.5000000,    29.1352348,    30.8677063, 
+       32.7031975,    34.6478271,    36.7080956,    38.8908730,    41.2034454,    43.6535301,    46.2493019,    48.9994278, 
+       51.9130859,    55.0000000,    58.2704697,    61.7354126,    65.4063950,    69.2956543,    73.4161911,    77.7817459, 
+       82.4068909,    87.3070602,    92.4986038,    97.9988556,   103.8261719,   110.0000000,   116.5409393,   123.4708252, 
+      130.8127899,   138.5913086,   146.8323822,   155.5634918,   164.8137817,   174.6141205,   184.9972076,   195.9977112, 
+      207.6523438,   220.0000000,   233.0818787,   246.9416504,   261.6255798,   277.1826172,   293.6647644,   311.1269836, 
+      329.6275635,   349.2282410,   369.9944153,   391.9954224,   415.3046875,   440.0000000,   466.1637573,   493.8833008, 
+      523.2511597,   554.3652344,   587.3295288,   622.2539673,   659.2551270,   698.4564819,   739.9888306,   783.9908447, 
+      830.6093750,   880.0000000,   932.3275146,   987.7666016,  1046.5023193,  1108.7304688,  1174.6590576,  1244.5079346, 
+     1318.5102539,  1396.9129639,  1479.9776611,  1567.9816895,  1661.2187500,  1760.0000000,  1864.6550293,  1975.5332031, 
+     2093.0046387,  2217.4609375,  2349.3181152,  2489.0158691,  2637.0205078,  2793.8259277,  2959.9553223,  3135.9633789, 
+     3322.4375000,  3520.0000000,  3729.3100586,  3951.0664062,  4186.0092773,  4434.9218750,  4698.6362305,  4978.0317383, 
+     5274.0410156,  5587.6518555,  5919.9106445,  6271.9267578,  6644.8750000,  7040.0000000,  7458.6201172,  7902.1328125, 
+     8372.0185547,  8869.8437500,  9397.2724609,  9956.0634766, 10548.0820312, 11175.3037109, 11839.8212891, 12543.8535156
+};
--- a/src/synth/synth.cpp
+++ b/src/synth/synth.cpp
@ -1,18 +1,18 @@
-#include <iostream>
+#include <cstdio>

 #include "synth/synth.h"

 void Synth::noteOn(int ch, int note, int vel) {
    channels[ch].noteOn(note, vel);
-    std::cout << "Note On: ch=" << ch << " note=" << note << " vel=" << vel << std::endl;
+    printf("Note On: ch=%d note=%d vel=%d\n", ch, note, vel);
 }

 void Synth::noteOff(int ch, int note) {
    channels[ch].noteOff(note);
-    std::cout << "Note Off: ch=" << ch << " note=" << note << std::endl;
+    printf("Note Off: ch=%d note=%d\n", ch, note);
 }

 void Synth::control(int ch, int cc, int val) {
    channels[ch].control(cc, val);
-    std::cout << "Controller: ch=" << ch << " cc=" << cc << " val=" << val << std::endl;
+    printf("Controller: ch=%d cc=%d val=%d\n", ch, cc, val);
 }
--- a/src/synth/voicemanager.cpp
+++ b/src/synth/voicemanager.cpp
@ -1,4 +1,4 @@
-#include <iostream>
+#include <cstdio>

 #include "synth/voicemanager.h"

@ -20,10 +20,11 @@ Voice * VoiceManager::get(channel_t channel) {
    voiceData.serial = serial++;
    voiceData.voice.reset();

+    putchar('\n');
    for(VoiceData& vd : voices) {
-        std::cout << "channel=" << vd.channel << " serial=" << vd.serial << " idle=" << vd.voice.isIdle() << " note=" << vd.voice.note << std::endl;
+        printf("channel=%d serial=%d idle=%d note=%d\n", vd.channel, vd.serial, vd.voice.isIdle(), vd.voice.note);
    }
-    std::cout << std::endl;
+    putchar('\n');

    return &voiceData.voice;
 }
@ -38,4 +39,4 @@ Voice** VoiceManager::getChannelVoices(channel_t channel) {
    }
    *voice = NULL;
    return result;
-}
+}
--- a/src/synthapp.cpp
+++ b/src/synthapp.cpp
@ -1,6 +1,6 @@
 #include <cstdlib>
+#include <cstdio>
 #include <cmath>
-#include <iostream>

 #include "synth/globals.h"

@ -10,6 +10,7 @@
 using namespace std;

 // PortAudio callback for audio I/O
+bool firstPACallback = true;
 static int paCallback(
        const void *inputBuffer,
        void *outputBuffer,
@ -20,6 +21,11 @@ static int paCallback(
    
    SynthApp *app = (SynthApp*) userData;

+    if(firstPACallback) {
+        printf("Buffer size is %ld frames\n", framesPerBuffer);
+        firstPACallback = false;
+    }
+
    PmEvent events[16];
    int numEvents = Pm_Read(app->pmStream, events, 16);
    for(int i = 0; i < numEvents; ++i) {
@ -40,13 +46,6 @@ static int paCallback(
            int val = Pm_MessageData2(msg);
            app->synth.control(ch, cc, val);
        }
-        /*
-        cout << "MIDI:";
-        for(int j = 0; j < 24; j += 8) {
-            cout << " " << hex << ((msg >> j) & 0xFF);
-        }
-        cout << endl;
-        */
    }

    float *out = (float*) outputBuffer;
@ -90,19 +89,22 @@ bool SynthApp::OnInit() {
    }

    int pmDeviceCount = Pm_CountDevices();
-    cout << "Select MIDI input device:" << endl;
+    putchar('\n');
+    printf("Select MIDI input device:\n\n");
    for(int i = 0; i < pmDeviceCount; ++i) {
        const PmDeviceInfo* deviceInfo = Pm_GetDeviceInfo(i);
        if(!deviceInfo->input) {
            continue;
        }
-        cout << i << ". " << deviceInfo->name << endl;
+        printf("%d. %s\n", i, deviceInfo->name);
    }
+    putchar('\n');
    int pmDeviceIndex;
    for(;;) { // loop for input until valid choice is made
-        string input;
-        getline(cin, input);
-        //string input = "1";
+        printf("Number: ");
+        char input[4];
+        fgets(input, 4, stdin);
+        //const char* input = "1";
        try {
            pmDeviceIndex = stoi(input);
            if(     pmDeviceIndex >= 0 &&
@ -111,23 +113,27 @@ bool SynthApp::OnInit() {
                break;
            }
        } catch(...) { } // stoi() throws an exeption for invalid integers
-        cout << "Invalid selection" << endl;   
+        printf("Invalid selection\n");
    }

+    putchar('\n');
+
    PaHostApiIndex paDeviceCount = Pa_GetDeviceCount();
-    cout << "Select audio output device:" << endl;
+    printf("Select audio output device:\n\n");
    for(int i = 0; i < paDeviceCount; ++i) {
        const PaDeviceInfo* deviceInfo = Pa_GetDeviceInfo(i);
        if(deviceInfo->maxOutputChannels < 2) {
            continue;
        }
-        cout << i << ". " << deviceInfo->name << " (" << Pa_GetHostApiInfo(deviceInfo->hostApi)->name << ")" << endl;
+        printf("%d. %s (%s)\n", i, deviceInfo->name, Pa_GetHostApiInfo(deviceInfo->hostApi)->name);
    }
+    putchar('\n');
    PaHostApiIndex paDeviceIndex;
    for(;;) { // loop for input until valid choice is made
-        string input;
-        getline(cin, input);
-        //string input = "4";
+        printf("Number: ");
+        char input[4];
+        fgets(input, 4, stdin);
+        //const char* input = "5";
        try {
            paDeviceIndex = stoi(input);
            if(     paDeviceIndex >= 0 &&
@ -136,11 +142,11 @@ bool SynthApp::OnInit() {
                break;
            }
        } catch(...) { } // stoi() throws an exeption for invalid integers
-        cout << "Invalid selection" << endl;   
+        printf("Invalid selection\n");
    }

    // Open MIDI input
-    PmError pmError = Pm_OpenInput(
+    pmErr = Pm_OpenInput(
        &pmStream,
        pmDeviceIndex,
        NULL,
@ -151,18 +157,25 @@ bool SynthApp::OnInit() {
        handlePMError(pmErr);
    }

+    const PaDeviceInfo* deviceInfo = Pa_GetDeviceInfo(paDeviceIndex);
+
+    putchar('\n');
+    printf("Default sample rate is %.0f Hz\n", deviceInfo->defaultSampleRate);
+    printf("Default low input latency is %.0f samples\n", deviceInfo->defaultSampleRate * deviceInfo->defaultLowOutputLatency);
+    putchar('\n');
+
    // Configure/start audio output stream
    PaStreamParameters paStreamParams;
    paStreamParams.device = paDeviceIndex;
    paStreamParams.channelCount = 2;
    paStreamParams.sampleFormat = paFloat32;
-    paStreamParams.suggestedLatency = 512.0 / SAMPLE_RATE;
+    paStreamParams.suggestedLatency = deviceInfo->defaultLowOutputLatency;
    paStreamParams.hostApiSpecificStreamInfo = NULL;
    paErr = Pa_OpenStream(
        &paStream,
        NULL,               // no input channels
        &paStreamParams,    // stereo output
-        SAMPLE_RATE,
+        deviceInfo->defaultSampleRate,
        0,                  // frames per buffer
        paNoFlag,
        paCallback,
@ -176,7 +189,7 @@ bool SynthApp::OnInit() {
    }

    const PaStreamInfo *paStreamInfo = Pa_GetStreamInfo(paStream);
-    cout << "Latency: " << round(1000 * paStreamInfo->outputLatency) << " ms" << endl;
+    printf("Reported latency is %d frames\n", (int) round(SAMPLE_RATE * paStreamInfo->outputLatency));

    wxFrame *frame = new SynthFrame();
    frame->Show(true);
@ -197,7 +210,7 @@ int SynthApp::OnExit() {
        handlePMError(pmErr);
    }
    Pa_Terminate();
-    cout << "Terminating" << endl;
+    printf("\nTerminating\n");

    return 0;
 }
--- a/xctrace-command.txt
+++ b/xctrace-command.txt
@ -1 +1 @@
- xctrace record --template 'Time Profiler' --target-stdin - --target-stdout - --launch ./build/main
+xctrace record --template 'Time Profiler' --launch ./build/main