=== modified file 'mixxx/src/engine/enginefilterblock.cpp'
--- mixxx/src/engine/enginefilterblock.cpp	2012-05-01 14:17:19 +0000
+++ mixxx/src/engine/enginefilterblock.cpp	2013-01-01 00:06:57 +0000
@@ -23,6 +23,7 @@
 #include "engine/enginefilter.h"
 #include "engine/enginefilterbutterworth8.h"
 #include "sampleutil.h"
+#include "util/timer.h"
 
 ControlPotmeter* EngineFilterBlock::s_loEqFreq = NULL;
 ControlPotmeter* EngineFilterBlock::s_hiEqFreq = NULL;
@@ -88,6 +89,10 @@
     memset(m_pTemp1, 0, sizeof(CSAMPLE) * MAX_BUFFER_LEN);
     memset(m_pTemp2, 0, sizeof(CSAMPLE) * MAX_BUFFER_LEN);
     memset(m_pTemp3, 0, sizeof(CSAMPLE) * MAX_BUFFER_LEN);
+
+    m_lowCur = filterpotLow->get();
+    m_midCur = filterpotMid->get();
+    m_highCur = filterpotHigh->get();
 }
 
 EngineFilterBlock::~EngineFilterBlock()
@@ -158,17 +163,36 @@
     if (filterKillHigh->get()==0.)
         fHigh = filterpotHigh->get(); //*1.2;
 
+
 #ifndef __LOFI__
     setFilters();
 #endif
 
+
     low->process(pIn, m_pTemp1, iBufferSize);
     band->process(pIn, m_pTemp2, iBufferSize);
     high->process(pIn, m_pTemp3, iBufferSize);
 
-    SampleUtil::copy3WithGain(pOutput,
-                              m_pTemp1, fLow,
-                              m_pTemp2, fMid,
-                              m_pTemp3, fHigh, iBufferSize);
+    fLow = fLow > 0 ? 0 : 1;
+    fMid = fMid > 0 ? 0 : 1;
+    fHigh = fHigh > 0 ? 0 : 1;
+
+    for (int i = 0; i < iBufferSize; ++i) {
+        pOutput[i] = m_pTemp1[i] * fLow + m_pTemp2[i] * fMid + m_pTemp3[i] * fHigh;
+    }
+    {
+        ScopedTimer t("EngineFilterBlock SampleUtil::rampCopy3WithGain");
+        SampleUtil::rampCopy3WithGain(pOutput,
+                                      m_pTemp1, &m_lowCur, fLow,
+                                      m_pTemp2, &m_midCur, fMid,
+                                      m_pTemp3, &m_highCur, fHigh, iBufferSize);
+    }
+    {
+        ScopedTimer t("EngineFilterBlock SampleUtil::copy3WithGain");
+        SampleUtil::copy3WithGain(pOutput,
+                                  m_pTemp1, fLow,
+                                  m_pTemp2, fMid,
+                                  m_pTemp3, fHigh, iBufferSize);
+    }
 }
 

=== modified file 'mixxx/src/engine/enginefilterblock.h'
--- mixxx/src/engine/enginefilterblock.h	2011-08-11 13:26:39 +0000
+++ mixxx/src/engine/enginefilterblock.h	2012-12-31 23:57:33 +0000
@@ -54,6 +54,8 @@
 
     int ilowFreq, ihighFreq;
     bool blofi;
+
+    CSAMPLE m_lowCur, m_midCur, m_highCur;
 };
 
 #endif

=== modified file 'mixxx/src/sampleutil.cpp'
--- mixxx/src/sampleutil.cpp	2011-12-08 11:47:54 +0000
+++ mixxx/src/sampleutil.cpp	2013-01-01 00:01:09 +0000
@@ -423,19 +423,19 @@
                                const CSAMPLE* pSrc2, CSAMPLE gain2,
                                const CSAMPLE* pSrc3, CSAMPLE gain3,
                                int iNumSamples) {
-    if (gain1 == 0.0f) {
-        return copy2WithGain(pDest, pSrc2, gain2, pSrc3, gain3, iNumSamples);
-    }
-    if (gain2 == 0.0f) {
-        return copy2WithGain(pDest, pSrc1, gain1, pSrc3, gain3, iNumSamples);
-    }
-    if (gain3 == 0.0f) {
-        return copy2WithGain(pDest, pSrc1, gain1, pSrc2, gain2, iNumSamples);
-    }
-    if (m_sOptimizationsOn) {
-        return sseCopy3WithGain(pDest, pSrc1, gain1, pSrc2, gain2,
-                                pSrc3, gain3, iNumSamples);
-    }
+    // if (gain1 == 0.0f) {
+    //     return copy2WithGain(pDest, pSrc2, gain2, pSrc3, gain3, iNumSamples);
+    // }
+    // if (gain2 == 0.0f) {
+    //     return copy2WithGain(pDest, pSrc1, gain1, pSrc3, gain3, iNumSamples);
+    // }
+    // if (gain3 == 0.0f) {
+    //     return copy2WithGain(pDest, pSrc1, gain1, pSrc2, gain2, iNumSamples);
+    // }
+    // if (m_sOptimizationsOn) {
+    //     return sseCopy3WithGain(pDest, pSrc1, gain1, pSrc2, gain2,
+    //                             pSrc3, gain3, iNumSamples);
+    // }
 
     for (int i = 0; i < iNumSamples; ++i) {
         pDest[i] = pSrc1[i] * gain1 + pSrc2[i] * gain2 + pSrc3[i] * gain3;
@@ -443,6 +443,34 @@
 }
 
 // static
+void SampleUtil::rampCopy3WithGain(CSAMPLE* pDest,
+                                   const CSAMPLE* pSrc1, CSAMPLE* oldGain1, CSAMPLE gain1,
+                                   const CSAMPLE* pSrc2, CSAMPLE* oldGain2, CSAMPLE gain2,
+                                   const CSAMPLE* pSrc3, CSAMPLE* oldGain3, CSAMPLE gain3,
+                                   int iNumSamples) {
+
+  CSAMPLE a = *oldGain1;
+  const CSAMPLE da = (gain1 - a)/iNumSamples;
+
+  CSAMPLE b = *oldGain2;
+  const CSAMPLE db = (gain2 - b)/iNumSamples;
+
+  CSAMPLE c = *oldGain3;
+  const CSAMPLE dc = (gain3 - c)/iNumSamples;
+
+
+  for (int i = 0; i < iNumSamples; ++i) {
+      a += da; b += db; c += dc;
+      pDest[i] = pSrc1[i] * a + pSrc2[i] * b + pSrc3[i] * c;
+  }
+
+	// update  current gain of the calling instance
+	*oldGain1 = a;
+  *oldGain1 = b;
+  *oldGain1 = c;
+}
+
+// static
 void SampleUtil::sseCopy3WithGain(CSAMPLE* pDest,
                                   const CSAMPLE* pSrc1, CSAMPLE gain1,
                                   const CSAMPLE* pSrc2, CSAMPLE gain2,

=== modified file 'mixxx/src/sampleutil.h'
--- mixxx/src/sampleutil.h	2012-04-08 02:31:42 +0000
+++ mixxx/src/sampleutil.h	2012-12-31 23:57:09 +0000
@@ -87,6 +87,12 @@
                               const CSAMPLE* pSrc3, CSAMPLE gain3,
                               int iNumSamples);
 
+    static void rampCopy3WithGain(CSAMPLE* pDest,
+                                  const CSAMPLE* pSrc1, CSAMPLE* oldGain1, CSAMPLE gain1,
+                                  const CSAMPLE* pSrc2, CSAMPLE* oldGain2, CSAMPLE gain2,
+                                  const CSAMPLE* pSrc3, CSAMPLE* oldGain3, CSAMPLE gain3,
+                                  int iNumSamples);
+
     // Copies the sum of each channel, multiplied by its gain into pDest
     static void copy4WithGain(CSAMPLE* pDest,
                               const CSAMPLE* pSrc1, CSAMPLE gain1,