diff --git a/release-packaging/Classes/FluidBufNoveltyFeature.sc b/release-packaging/Classes/FluidBufNoveltyFeature.sc
index 868c37a2..1fca9ace 100644
--- a/release-packaging/Classes/FluidBufNoveltyFeature.sc
+++ b/release-packaging/Classes/FluidBufNoveltyFeature.sc
@@ -6,6 +6,10 @@ FluidBufNoveltyFeature : FluidBufProcessor {
 
 		source = source.asUGenInput;
 		features = features.asUGenInput;
+		algorithm = FluidNoveltySlice.prSelectAlgorithm(algorithm) ?? {
+			("FluidBufNoveltySlice: % is not a recognised algorithm")
+			.format(algorithm).throw;
+		};
 
 		source.isNil.if {"FluidBufNoveltyFeature:  Invalid source buffer".throw};
 		features.isNil.if {"FluidBufNoveltyFeature:  Invalid features buffer".throw};
@@ -20,6 +24,11 @@ FluidBufNoveltyFeature : FluidBufProcessor {
 
         source = source.asUGenInput;
         features = features.asUGenInput;
+		algorithm = FluidNoveltySlice.prSelectAlgorithm(algorithm);
+		if (algorithm.isNil or: algorithm.isUGen) {
+			("FluidBufNoveltySlice: % is not a recognised algorithm")
+			.format(algorithm).throw;
+		};
 
         source.isNil.if {"FluidBufNoveltyFeature:  Invalid source buffer".throw};
         features.isNil.if {"FluidBufNoveltyFeature:  Invalid features buffer".throw};
@@ -40,6 +49,11 @@ FluidBufNoveltyFeature : FluidBufProcessor {
 
         source.isNil.if {"FluidBufNoveltyFeature:  Invalid source buffer".throw};
         features.isNil.if {"FluidBufNoveltyFeature:  Invalid features buffer".throw};
+		algorithm = FluidNoveltySlice.prSelectAlgorithm(algorithm);
+		if (algorithm.isNil or: algorithm.isUGen) {
+			("FluidBufNoveltySlice: % is not a recognised algorithm")
+			.format(algorithm).throw;
+		};
 
 		^this.new(
 			server, nil, [features]
diff --git a/release-packaging/Classes/FluidBufNoveltySlice.sc b/release-packaging/Classes/FluidBufNoveltySlice.sc
index b53820e5..82952fea 100644
--- a/release-packaging/Classes/FluidBufNoveltySlice.sc
+++ b/release-packaging/Classes/FluidBufNoveltySlice.sc
@@ -1,11 +1,15 @@
 FluidBufNoveltySlice : FluidBufProcessor {
 
-    *kr  { |source, startFrame = 0, numFrames = -1, startChan = 0, numChans = -1, indices, algorithm = 0, kernelSize = 3, threshold = 0.5, filterSize = 1, minSliceLength = 2, windowSize = 1024, hopSize = -1, fftSize = -1, trig = 1 , blocking = 0| 
+	*kr  { |source, startFrame = 0, numFrames = -1, startChan = 0, numChans = -1, indices, algorithm = 0, kernelSize = 3, threshold = 0.5, filterSize = 1, minSliceLength = 2, windowSize = 1024, hopSize = -1, fftSize = -1, trig = 1 , blocking = 0|
 
         var maxFFTSize = if (fftSize == -1) {windowSize.nextPowerOfTwo} {fftSize};
 
 		source = source.asUGenInput;
 		indices = indices.asUGenInput;
+		algorithm = FluidNoveltySlice.prSelectAlgorithm(algorithm) ?? {
+			("FluidBufNoveltySlice: % is not a recognised algorithm")
+			.format(algorithm).throw;
+		};
 
 		source.isNil.if {"FluidBufNoveltySlice:  Invalid source buffer".throw};
 		indices.isNil.if {"FluidBufNoveltySlice:  Invalid features buffer".throw};
@@ -15,15 +19,20 @@ FluidBufNoveltySlice : FluidBufProcessor {
 	}
 
     *process { |server, source, startFrame = 0, numFrames = -1, startChan = 0, numChans = -1, indices, algorithm= 0, kernelSize = 3, threshold = 0.5, filterSize = 1, minSliceLength = 2, windowSize = 1024, hopSize = -1, fftSize = -1, freeWhenDone = true, action |
-        
+
         var maxFFTSize = if (fftSize == -1) {windowSize.nextPowerOfTwo} {fftSize};
 
         source = source.asUGenInput;
         indices = indices.asUGenInput;
+        algorithm = FluidNoveltySlice.prSelectAlgorithm(algorithm);
+	if (algorithm.isNil or: algorithm.isUGen) {
+            ("FluidBufNoveltySlice: % is not a recognised algorithm")
+            .format(algorithm).throw;
+        };
 
         source.isNil.if {"FluidBufNoveltySlice:  Invalid source buffer".throw};
         indices.isNil.if {"FluidBufNoveltySlice:  Invalid features buffer".throw};
-        
+
 		^this.new(
 			server, nil, [indices]
 		).processList(
@@ -32,15 +41,20 @@ FluidBufNoveltySlice : FluidBufProcessor {
 	}
 
     *processBlocking { |server, source, startFrame = 0, numFrames = -1, startChan = 0, numChans = -1, indices, algorithm= 0, kernelSize = 3, threshold = 0.5, filterSize = 1, minSliceLength = 2, windowSize = 1024, hopSize = -1, fftSize = -1, freeWhenDone = true, action |
-        
+
         var maxFFTSize = if (fftSize == -1) {windowSize.nextPowerOfTwo} {fftSize};
 
         source = source.asUGenInput;
         indices = indices.asUGenInput;
+        algorithm = FluidNoveltySlice.prSelectAlgorithm(algorithm);
+	if (algorithm.isNil or: algorithm.isUGen) {
+            ("FluidBufNoveltySlice: % is not a recognised algorithm")
+            .format(algorithm).throw;
+        };
 
         source.isNil.if {"FluidBufNoveltySlice:  Invalid source buffer".throw};
         indices.isNil.if {"FluidBufNoveltySlice:  Invalid features buffer".throw};
-        
+
 		^this.new(
 			server, nil, [indices]
 		).processList(
diff --git a/release-packaging/Classes/FluidBufOnsetFeature.sc b/release-packaging/Classes/FluidBufOnsetFeature.sc
index 6ea08b01..1b3235c8 100644
--- a/release-packaging/Classes/FluidBufOnsetFeature.sc
+++ b/release-packaging/Classes/FluidBufOnsetFeature.sc
@@ -5,6 +5,10 @@ FluidBufOnsetFeature : FluidBufProcessor {
 
         source = source.asUGenInput;
         features = features.asUGenInput;
+        metric = FluidOnsetSlice.prSelectMetric(metric) ?? {
+            ("FluidBufOnsetSlice: % is not a recognised metric")
+            .format(metric).throw;
+        };
 
         source.isNil.if {"FluidBufOnsetFeature:  Invalid source buffer".throw};
         features.isNil.if {"FluidBufOnsetFeature:  Invalid features buffer".throw};
@@ -18,6 +22,11 @@ FluidBufOnsetFeature : FluidBufProcessor {
 
         source = source.asUGenInput;
         features = features.asUGenInput;
+        metric = FluidOnsetSlice.prSelectMetric(metric);
+	if (metric.isNil or: metric.isUGen) {
+            ("FluidBufOnsetSlice: % is not a recognised metric")
+            .format(metric).throw;
+        };
 
         source.isNil.if {"FluidBufOnsetFeature:  Invalid source buffer".throw};
         features.isNil.if {"FluidBufOnsetFeature:  Invalid features buffer".throw};
@@ -35,6 +44,11 @@ FluidBufOnsetFeature : FluidBufProcessor {
 
         source = source.asUGenInput;
         features = features.asUGenInput;
+        metric = FluidOnsetSlice.prSelectMetric(metric);
+	if (metric.isNil or: metric.isUGen) {
+            ("FluidBufOnsetSlice: % is not a recognised metric")
+            .format(metric).throw;
+        };
 
         source.isNil.if {"FluidBufOnsetFeature:  Invalid source buffer".throw};
         features.isNil.if {"FluidBufOnsetFeature:  Invalid features buffer".throw};
diff --git a/release-packaging/Classes/FluidBufOnsetSlice.sc b/release-packaging/Classes/FluidBufOnsetSlice.sc
index 2f9a7548..0a3f6d78 100644
--- a/release-packaging/Classes/FluidBufOnsetSlice.sc
+++ b/release-packaging/Classes/FluidBufOnsetSlice.sc
@@ -1,27 +1,37 @@
 FluidBufOnsetSlice : FluidBufProcessor {
-    *kr  { |source, startFrame = 0, numFrames = -1, startChan = 0, numChans = -1, indices, metric = 0, threshold = 0.5, minSliceLength = 2, filterSize = 5, frameDelta = 0, windowSize = 1024, hopSize = -1, fftSize = -1, trig = 1, blocking = 0| 
-        
+
+    *kr  { |source, startFrame = 0, numFrames = -1, startChan = 0, numChans = -1, indices, metric = 0, threshold = 0.5, minSliceLength = 2, filterSize = 5, frameDelta = 0, windowSize = 1024, hopSize = -1, fftSize = -1, trig = 1, blocking = 0|
+
         var maxFFTSize = if (fftSize == -1) {windowSize.nextPowerOfTwo} {fftSize};
 
         source = source.asUGenInput;
         indices = indices.asUGenInput;
+        metric = FluidOnsetSlice.prSelectMetric(metric) ?? {
+            ("FluidBufOnsetSlice: % is not a recognised metric")
+            .format(metric).throw;
+        };
 
         source.isNil.if {"FluidBufOnsetSlice:  Invalid source buffer".throw};
         indices.isNil.if {"FluidBufOnsetSlice:  Invalid features buffer".throw};
-                
+
 		^FluidProxyUgen.kr(\FluidBufOnsetSliceTrigger, -1, source, startFrame, numFrames, startChan, numChans, indices, metric, threshold, minSliceLength, filterSize, frameDelta, windowSize, hopSize, fftSize, maxFFTSize, trig, blocking);
 	}
 
     *process { |server, source, startFrame = 0, numFrames = -1, startChan = 0, numChans = -1, indices, metric = 0, threshold = 0.5, minSliceLength = 2, filterSize = 5, frameDelta = 0, windowSize = 1024, hopSize = -1, fftSize = -1, freeWhenDone = true, action|
-        
+
         var maxFFTSize = if (fftSize == -1) {windowSize.nextPowerOfTwo} {fftSize};
 
         source = source.asUGenInput;
         indices = indices.asUGenInput;
+        metric = FluidOnsetSlice.prSelectMetric(metric);
+	if (metric.isNil or: metric.isUGen) {
+            ("FluidBufOnsetSlice: % is not a recognised metric")
+            .format(metric).throw;
+        };
 
         source.isNil.if {"FluidBufOnsetSlice:  Invalid source buffer".throw};
         indices.isNil.if {"FluidBufOnsetSlice:  Invalid features buffer".throw};
-                
+
 		^this.new(
 			server, nil, [indices]
 		).processList(
@@ -30,15 +40,20 @@ FluidBufOnsetSlice : FluidBufProcessor {
 	}
 
     *processBlocking { |server, source, startFrame = 0, numFrames = -1, startChan = 0, numChans = -1, indices, metric = 0, threshold = 0.5, minSliceLength = 2, filterSize = 5, frameDelta = 0, windowSize = 1024, hopSize = -1, fftSize = -1, freeWhenDone = true, action|
-        
+
         var maxFFTSize = if (fftSize == -1) {windowSize.nextPowerOfTwo} {fftSize};
 
         source = source.asUGenInput;
         indices = indices.asUGenInput;
+        metric = FluidOnsetSlice.prSelectMetric(metric);
+	if (metric.isNil or: metric.isUGen) {
+            ("FluidBufOnsetSlice: % is not a recognised metric")
+            .format(metric).throw;
+        };
 
         source.isNil.if {"FluidBufOnsetSlice:  Invalid source buffer".throw};
         indices.isNil.if {"FluidBufOnsetSlice:  Invalid features buffer".throw};
-                
+
 		^this.new(
 			server, nil, [indices]
 		).processList(
diff --git a/release-packaging/Classes/FluidNoveltyFeature.sc b/release-packaging/Classes/FluidNoveltyFeature.sc
index ddb63139..a83df30f 100644
--- a/release-packaging/Classes/FluidNoveltyFeature.sc
+++ b/release-packaging/Classes/FluidNoveltyFeature.sc
@@ -1,13 +1,19 @@
 FluidNoveltyFeature : FluidRTUGen {
 	*kr { arg in = 0, algorithm = 0, kernelSize = 3, filterSize = 1, windowSize = 1024, hopSize = -1, fftSize = -1, maxFFTSize = -1, maxKernelSize, maxFilterSize;
-        
-        maxKernelSize = maxKernelSize ? kernelSize; 
-        maxFilterSize = maxFilterSize ? filterSize; 
-        
+
+        maxKernelSize = maxKernelSize ? kernelSize;
+        maxFilterSize = maxFilterSize ? filterSize;
+        algorithm = FluidNoveltySlice.prSelectAlgorithm(algorithm)  ?? {
+            ("FluidNoveltySlice: % is not a recognised algorithm").format(algorithm);
+        };
+
 		^this.multiNew('control', in.asAudioRateInput(this), algorithm, kernelSize, maxKernelSize, filterSize, maxFilterSize, windowSize, hopSize, fftSize, maxFFTSize)
 	}
-    
+
 	checkInputs {
+		if([\scalar, \control].includes(inputs.at(1).rate).not) {
+			^(": invalid algorithm");
+		    };
 		if(inputs.at(9).rate != 'scalar') {
 			^(": maxFFTSize cannot be modulated.");
 			};
diff --git a/release-packaging/Classes/FluidNoveltySlice.sc b/release-packaging/Classes/FluidNoveltySlice.sc
index 9dd78dfa..da43d54f 100644
--- a/release-packaging/Classes/FluidNoveltySlice.sc
+++ b/release-packaging/Classes/FluidNoveltySlice.sc
@@ -1,20 +1,35 @@
 FluidNoveltySlice : FluidRTUGen {
 
-	const <spectrum = 0;
-	const <mfcc = 1;
-	const <chroma = 2;
-	const <pitch = 3;
-	const <loudness = 4;
+	const <algorithms = #[\spectrum, \mfcc, \chroma, \pitch, \loudness];
+
+	*prSelectAlgorithm { |sym|
+		if (sym.isUGen) { ^sym };
+		if (sym.isNumber) {
+			if (sym >= 0 && (sym < algorithms.size)) {
+				^sym
+			} {
+				^nil
+			}
+		};
+		^algorithms.indexOf(sym.asSymbol)
+	}
 
 	*ar { arg in = 0, algorithm = 0, kernelSize = 3, threshold = 0.8, filterSize = 1, minSliceLength = 2, windowSize = 1024, hopSize = -1, fftSize = -1, maxFFTSize = -1, maxKernelSize, maxFilterSize;
-        
+
         maxKernelSize = maxKernelSize ? kernelSize;
-        maxFilterSize = maxFilterSize ? filterSize; 
-        
+        maxFilterSize = maxFilterSize ? filterSize;
+
+        algorithm = this.prSelectAlgorithm(algorithm)  ?? {
+            ("FluidNoveltySlice: % is not a recognised algorithm").format(algorithm);
+        };
+
 		^this.multiNew('audio', in.asAudioRateInput(this), algorithm, kernelSize, maxKernelSize, threshold, filterSize,  maxFilterSize, minSliceLength, windowSize, hopSize, fftSize, maxFFTSize)
 	}
 
 	checkInputs {
+		if([\scalar, \control].includes(inputs.at(1).rate).not) {
+			^(": invalid algorithm");
+		    };
 		if(inputs.at(11).rate != 'scalar') {
 			^(": maxFFTSize cannot be modulated.");
 			};
diff --git a/release-packaging/Classes/FluidOnsetFeature.sc b/release-packaging/Classes/FluidOnsetFeature.sc
index 894b3e90..d5b7786a 100644
--- a/release-packaging/Classes/FluidOnsetFeature.sc
+++ b/release-packaging/Classes/FluidOnsetFeature.sc
@@ -1,8 +1,16 @@
 FluidOnsetFeature : FluidRTUGen {
 	*kr { arg in = 0, metric = 0, filterSize = 5, frameDelta = 0, windowSize = 1024, hopSize = -1, fftSize = -1, maxFFTSize = -1;
+
+		metric = FluidOnsetSlice.prSelectMetric(metric) ?? {
+			("% is not a recognised metric").format(metric);
+		};
+
 		^this.multiNew('control', in.asAudioRateInput(this), metric, filterSize, frameDelta, windowSize, hopSize, fftSize, maxFFTSize)
 	}
 	checkInputs {
+		if([\scalar, \control].includes(inputs.at(1).rate).not) {
+			^(": invalid metric");
+		    };
 		if(inputs.at(7).rate != 'scalar') {
 			^(": maxFFTSize cannot be modulated.");
 			};
diff --git a/release-packaging/Classes/FluidOnsetSlice.sc b/release-packaging/Classes/FluidOnsetSlice.sc
index 91dd2c8d..507e1286 100644
--- a/release-packaging/Classes/FluidOnsetSlice.sc
+++ b/release-packaging/Classes/FluidOnsetSlice.sc
@@ -1,20 +1,42 @@
 FluidOnsetSlice : FluidRTUGen {
 
-	const <power = 0;
-	const <hfc = 1;
-	const <flux = 2;
-	const <mkl = 3;
-	const <is = 4;
-	const <cosine = 5;
-	const <phase = 6;
-	const <wphase = 7;
-	const <complex = 8;
-	const <rcomplex = 9;
+	const <metrics = #[
+		\power,
+		\hfc,
+		\flux,
+		\mkl,
+		\is,
+		\cosine,
+		\phase,
+		\wphase,
+		\complex,
+		\rcomplex,
+	];
+
+	*prSelectMetric { |sym|
+		if (sym.isUGen) { ^sym };
+		if (sym.isNumber) {
+			if (sym >= 0 && (sym < metrics.size)) {
+				^sym
+			} {
+				^nil
+			}
+		};
+		^metrics.indexOf(sym.asSymbol)
+	}
 
 	*ar { arg in = 0, metric = 0, threshold = 0.5, minSliceLength = 2, filterSize = 5, frameDelta = 0, windowSize = 1024, hopSize = -1, fftSize = -1, maxFFTSize = -1;
+
+		metric = this.prSelectMetric(metric) ?? {
+			("% is not a recognised metric").format(metric);
+		};
+
 		^this.multiNew('audio', in.asAudioRateInput(this), metric, threshold, minSliceLength, filterSize, frameDelta, windowSize, hopSize, fftSize, maxFFTSize)
 	}
 	checkInputs {
+		if([\scalar, \control].includes(inputs.at(1).rate).not) {
+			^(": invalid metric");
+		    };
 		if(inputs.at(9).rate != 'scalar') {
 			^(": maxFFTSize cannot be modulated.");
 			};