diff --git a/modules/juce_audio_basics/utilities/juce_GenericInterpolator.h b/modules/juce_audio_basics/utilities/juce_GenericInterpolator.h
index 084927d24d..acc798b24a 100644
--- a/modules/juce_audio_basics/utilities/juce_GenericInterpolator.h
+++ b/modules/juce_audio_basics/utilities/juce_GenericInterpolator.h
@@ -39,6 +39,16 @@ namespace juce
 template <class InterpolatorTraits, int memorySize>
 class JUCE_API  GenericInterpolator
 {
+    static auto processReplacingCallback()
+    {
+        return [] (auto, auto newValue) { return newValue; };
+    }
+
+    static auto processAddingCallback (float gain)
+    {
+        return [gain] (auto oldValue, auto newValue) { return oldValue + gain * newValue; };
+    }
+
 public:
     GenericInterpolator() noexcept                        { reset(); }
 
@@ -81,7 +91,11 @@ public:
                  float* outputSamples,
                  int numOutputSamplesToProduce) noexcept
     {
-        return interpolate (speedRatio, inputSamples, outputSamples, numOutputSamplesToProduce);
+        return interpolateImpl (speedRatio,
+                                inputSamples,
+                                outputSamples,
+                                numOutputSamplesToProduce,
+                                processReplacingCallback());
     }
 
     /** Resamples a stream of samples.
@@ -106,8 +120,13 @@ public:
                  int numInputSamplesAvailable,
                  int wrapAround) noexcept
     {
-        return interpolate (speedRatio, inputSamples, outputSamples,
-                            numOutputSamplesToProduce, numInputSamplesAvailable, wrapAround);
+        return interpolateImpl (speedRatio,
+                                inputSamples,
+                                outputSamples,
+                                numOutputSamplesToProduce,
+                                numInputSamplesAvailable,
+                                wrapAround,
+                                processReplacingCallback());
     }
 
     /** Resamples a stream of samples, adding the results to the output data
@@ -131,7 +150,11 @@ public:
                        int numOutputSamplesToProduce,
                        float gain) noexcept
     {
-        return interpolateAdding (speedRatio, inputSamples, outputSamples, numOutputSamplesToProduce, gain);
+        return interpolateImpl (speedRatio,
+                                inputSamples,
+                                outputSamples,
+                                numOutputSamplesToProduce,
+                                processAddingCallback (gain));
     }
 
     /** Resamples a stream of samples, adding the results to the output data
@@ -162,8 +185,13 @@ public:
                        int wrapAround,
                        float gain) noexcept
     {
-        return interpolateAdding (speedRatio, inputSamples, outputSamples,
-                                  numOutputSamplesToProduce, numInputSamplesAvailable, wrapAround, gain);
+        return interpolateImpl (speedRatio,
+                                inputSamples,
+                                outputSamples,
+                                numOutputSamplesToProduce,
+                                numInputSamplesAvailable,
+                                wrapAround,
+                                processAddingCallback (gain));
     }
 
 private:
@@ -255,10 +283,89 @@ private:
     }
 
     //==============================================================================
-    int interpolate (double speedRatio,
-                     const float* input,
-                     float* output,
-                     int numOutputSamplesToProduce) noexcept
+    template <typename Process>
+    int interpolateImpl (double speedRatio,
+                         const float* input,
+                         float* output,
+                         int numOutputSamplesToProduce,
+                         int numInputSamplesAvailable,
+                         int wrap,
+                         Process process)
+    {
+        auto originalIn = input;
+        auto pos = subSamplePos;
+        bool exceeded = false;
+
+        const auto pushSample = [&]
+        {
+            if (exceeded)
+            {
+                pushInterpolationSample (0.0);
+            }
+            else
+            {
+                pushInterpolationSample (*input++);
+
+                if (--numInputSamplesAvailable <= 0)
+                {
+                    if (wrap > 0)
+                    {
+                        input -= wrap;
+                        numInputSamplesAvailable += wrap;
+                    }
+                    else
+                    {
+                        exceeded = true;
+                    }
+                }
+            }
+        };
+
+        if (speedRatio < 1.0)
+        {
+            for (int i = numOutputSamplesToProduce; --i >= 0;)
+            {
+                if (pos >= 1.0)
+                {
+                    pushSample();
+                    pos -= 1.0;
+                }
+
+                *output = process (*output, InterpolatorTraits::valueAtOffset (lastInputSamples, (float) pos, indexBuffer));
+                ++output;
+                pos += speedRatio;
+            }
+        }
+        else
+        {
+            for (int i = numOutputSamplesToProduce; --i >= 0;)
+            {
+                while (pos < speedRatio)
+                {
+                    pushSample();
+                    pos += 1.0;
+                }
+
+                pos -= speedRatio;
+                *output = process (*output, InterpolatorTraits::valueAtOffset (lastInputSamples, jmax (0.0f, 1.0f - (float) pos), indexBuffer));
+                ++output;
+            }
+        }
+
+        subSamplePos = pos;
+
+        if (wrap == 0)
+            return (int) (input - originalIn);
+
+        return ((int) (input - originalIn) + wrap) % wrap;
+    }
+
+    template <typename Process>
+    int interpolateImpl (double speedRatio,
+                         const float* input,
+                         float* output,
+                         int numOutputSamplesToProduce,
+                         Process process)
     {
         auto pos = subSamplePos;
         int numUsed = 0;
@@ -271,213 +378,8 @@ private:
                 pos -= 1.0;
             }
 
-            *output++ = InterpolatorTraits::valueAtOffset (lastInputSamples, (float) pos, indexBuffer);
-            pos += speedRatio;
-            --numOutputSamplesToProduce;
-        }
-
-        subSamplePos = pos;
-        return numUsed;
-    }
-
-    int interpolate (double speedRatio,
-                     const float* input, float* output,
-                     int numOutputSamplesToProduce,
-                     int numInputSamplesAvailable,
-                     int wrap) noexcept
-    {
-        auto originalIn = input;
-        auto pos = subSamplePos;
-        bool exceeded = false;
-
-        if (speedRatio < 1.0)
-        {
-            for (int i = numOutputSamplesToProduce; --i >= 0;)
-            {
-                if (pos >= 1.0)
-                {
-                    if (exceeded)
-                    {
-                        pushInterpolationSample (0.0f);
-                    }
-                    else
-                    {
-                        pushInterpolationSample (*input++);
-
-                        if (--numInputSamplesAvailable <= 0)
-                        {
-                            if (wrap > 0)
-                            {
-                                input -= wrap;
-                                numInputSamplesAvailable += wrap;
-                            }
-                            else
-                            {
-                                exceeded = true;
-                            }
-                        }
-                    }
-
-                    pos -= 1.0;
-                }
-
-                *output++ = InterpolatorTraits::valueAtOffset (lastInputSamples, (float) pos, indexBuffer);
-                pos += speedRatio;
-            }
-        }
-        else
-        {
-            for (int i = numOutputSamplesToProduce; --i >= 0;)
-            {
-                while (pos < speedRatio)
-                {
-                    if (exceeded)
-                    {
-                        pushInterpolationSample (0);
-                    }
-                    else
-                    {
-                        pushInterpolationSample (*input++);
-
-                        if (--numInputSamplesAvailable <= 0)
-                        {
-                            if (wrap > 0)
-                            {
-                                input -= wrap;
-                                numInputSamplesAvailable += wrap;
-                            }
-                            else
-                            {
-                                exceeded = true;
-                            }
-                        }
-                    }
-
-                    pos += 1.0;
-                }
-
-                pos -= speedRatio;
-                *output++ = InterpolatorTraits::valueAtOffset (lastInputSamples, jmax (0.0f, 1.0f - (float) pos), indexBuffer);
-            }
-        }
-
-        subSamplePos = pos;
-
-        if (wrap == 0)
-            return (int) (input - originalIn);
-
-        return ((int) (input - originalIn) + wrap) % wrap;
-    }
-
-    int interpolateAdding (double speedRatio,
-                           const float* input,
-                           float* output,
-                           int numOutputSamplesToProduce,
-                           int numInputSamplesAvailable,
-                           int wrap,
-                           float gain) noexcept
-    {
-        auto originalIn = input;
-        auto pos = subSamplePos;
-        bool exceeded = false;
-
-        if (speedRatio < 1.0)
-        {
-            for (int i = numOutputSamplesToProduce; --i >= 0;)
-            {
-                if (pos >= 1.0)
-                {
-                    if (exceeded)
-                    {
-                        pushInterpolationSample (0.0);
-                    }
-                    else
-                    {
-                        pushInterpolationSample (*input++);
-
-                        if (--numInputSamplesAvailable <= 0)
-                        {
-                            if (wrap > 0)
-                            {
-                                input -= wrap;
-                                numInputSamplesAvailable += wrap;
-                            }
-                            else
-                            {
-                                numInputSamplesAvailable = true;
-                            }
-                        }
-                    }
-
-                    pos -= 1.0;
-                }
-
-                *output++ += gain * InterpolatorTraits::valueAtOffset (lastInputSamples, (float) pos, indexBuffer);
-                pos += speedRatio;
-            }
-        }
-        else
-        {
-            for (int i = numOutputSamplesToProduce; --i >= 0;)
-            {
-                while (pos < speedRatio)
-                {
-                    if (exceeded)
-                    {
-                        pushInterpolationSample (0.0);
-                    }
-                    else
-                    {
-                        pushInterpolationSample (*input++);
-
-                        if (--numInputSamplesAvailable <= 0)
-                        {
-                            if (wrap > 0)
-                            {
-                                input -= wrap;
-                                numInputSamplesAvailable += wrap;
-                            }
-                            else
-                            {
-                                exceeded = true;
-                            }
-                        }
-                    }
-
-                    pos += 1.0;
-                }
-
-                pos -= speedRatio;
-                *output++ += gain * InterpolatorTraits::valueAtOffset (lastInputSamples, jmax (0.0f, 1.0f - (float) pos), indexBuffer);
-            }
-        }
-
-        subSamplePos = pos;
-
-        if (wrap == 0)
-            return (int) (input - originalIn);
-
-        return ((int) (input - originalIn) + wrap) % wrap;
-    }
-
-    int interpolateAdding (double speedRatio,
-                           const float* input,
-                           float* output,
-                           int numOutputSamplesToProduce,
-                           float gain) noexcept
-    {
-        auto pos = subSamplePos;
-        int numUsed = 0;
-
-        while (numOutputSamplesToProduce > 0)
-        {
-            while (pos >= 1.0)
-            {
-                pushInterpolationSample (input[numUsed++]);
-                pos -= 1.0;
-            }
-
-            *output++ += gain * InterpolatorTraits::valueAtOffset (lastInputSamples, (float) pos, indexBuffer);
+            *output = process (*output, InterpolatorTraits::valueAtOffset (lastInputSamples, (float) pos, indexBuffer));
+            ++output;
             pos += speedRatio;
             --numOutputSamplesToProduce;
         }