diff --git a/.travis.yml b/.travis.yml
index 4d2f9bb..e694ca2 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,7 +11,6 @@ jdk:
 addons:
   apt:
     packages:
-    - praat
     - sox
     - speech-tools
 
diff --git a/README.md b/README.md
index 70724ba..c1d6bf2 100644
--- a/README.md
+++ b/README.md
@@ -6,17 +6,17 @@ A male Scottish English limited-domain unit selection voice for [MaryTTS](http:/
 
 ## Prerequisites
 
-You will need to have [Java](https://www.java.com/), [Praat](http://praat.org/), [SoX](http://sox.sourceforge.net/), and the [Edinburgh Speech Tools](http://www.cstr.ed.ac.uk/projects/speech_tools/) installed.
+You will need to have [Java](https://www.java.com/), [SoX](http://sox.sourceforge.net/), and the [Edinburgh Speech Tools](http://www.cstr.ed.ac.uk/projects/speech_tools/) installed.
 On OSX with [Homebrew](http://brew.sh/), do
 ```
-$ brew cask install java praat
+$ brew cask install java
 $ brew install sox speech-tools
 ```
 as needed.
 
 On Debian-based Linux (including Ubuntu), do
 ```
-$ sudo apt-get install default-jdk praat sox speech-tools
+$ sudo apt-get install default-jdk sox speech-tools
 ```
 accordingly.
 
diff --git a/build.gradle b/build.gradle
index d68ad49..44a1e25 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,6 +1,6 @@
 plugins {
-    id 'de.dfki.mary.voicebuilding-legacy' version '5.2.0'
-    id 'de.dfki.mary.voicebuilding-festvox' version '5.2.0'
+    id 'de.dfki.mary.voicebuilding-legacy' version '5.3.2'
+    id 'de.dfki.mary.voicebuilding-festvox' version '5.3.2'
 }
 
 group 'de.dfki.mary'
diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar
index 3baa851..a5fe1cb 100644
Binary files a/gradle/wrapper/gradle-wrapper.jar and b/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 234357b..be280be 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,5 @@
-#Tue Aug 29 13:50:16 CEST 2017
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.14.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.5-bin.zip
diff --git a/gradlew b/gradlew
index 27309d9..cccdd3d 100755
--- a/gradlew
+++ b/gradlew
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+#!/usr/bin/env sh
 
 ##############################################################################
 ##
@@ -33,11 +33,11 @@ DEFAULT_JVM_OPTS=""
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD="maximum"
 
-warn ( ) {
+warn () {
     echo "$*"
 }
 
-die ( ) {
+die () {
     echo
     echo "$*"
     echo
@@ -154,11 +154,19 @@ if $cygwin ; then
     esac
 fi
 
-# Split up the JVM_OPTS And GRADLE_OPTS values into an array, following the shell quoting and substitution rules
-function splitJvmOpts() {
-    JVM_OPTS=("$@")
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
 }
-eval splitJvmOpts $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS
-JVM_OPTS[${#JVM_OPTS[*]}]="-Dorg.gradle.appname=$APP_BASE_NAME"
+APP_ARGS=$(save "$@")
 
-exec "$JAVACMD" "${JVM_OPTS[@]}" -classpath "$CLASSPATH" org.gradle.wrapper.GradleWrapperMain "$@"
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+  cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"
diff --git a/gradlew.bat b/gradlew.bat
index 832fdb6..f955316 100644
--- a/gradlew.bat
+++ b/gradlew.bat
@@ -49,7 +49,6 @@ goto fail
 @rem Get command-line arguments, handling Windows variants
 
 if not "%OS%" == "Windows_NT" goto win9xME_args
-if "%@eval[2+2]" == "4" goto 4NT_args
 
 :win9xME_args
 @rem Slurp the command line arguments.
@@ -60,11 +59,6 @@ set _SKIP=2
 if "x%~1" == "x" goto execute
 
 set CMD_LINE_ARGS=%*
-goto execute
-
-:4NT_args
-@rem Get arguments from the 4NT Shell from JP Software
-set CMD_LINE_ARGS=%$
 
 :execute
 @rem Setup the command line