diff --git a/speech/grpc/src/main/java/com/examples/cloud/speech/StreamingRecognizeClient.java b/speech/grpc/src/main/java/com/examples/cloud/speech/StreamingRecognizeClient.java
index a7da0e81f1e..d1a529a1216 100644
--- a/speech/grpc/src/main/java/com/examples/cloud/speech/StreamingRecognizeClient.java
+++ b/speech/grpc/src/main/java/com/examples/cloud/speech/StreamingRecognizeClient.java
@@ -18,6 +18,7 @@
 
 import static org.apache.log4j.ConsoleAppender.SYSTEM_OUT;
 
+import com.google.auth.oauth2.GoogleCredentials;
 import com.google.cloud.speech.v1beta1.RecognitionConfig;
 import com.google.cloud.speech.v1beta1.RecognitionConfig.AudioEncoding;
 import com.google.cloud.speech.v1beta1.SpeechGrpc;
@@ -28,6 +29,8 @@
 import com.google.protobuf.TextFormat;
 
 import io.grpc.ManagedChannel;
+import io.grpc.ManagedChannelBuilder;
+import io.grpc.auth.ClientAuthInterceptor;
 import io.grpc.stub.StreamObserver;
 
 import org.apache.commons.cli.CommandLine;
@@ -47,6 +50,7 @@
 import java.util.Arrays;
 import java.util.List;
 import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 
 
@@ -84,7 +88,7 @@ public StreamingRecognizeClient(ManagedChannel channel, String file, int samplin
     //Send log4j logs to Console
     //If you are going to run this on GCE, you might wish to integrate with gcloud-java logging.
     //See https://github.com/GoogleCloudPlatform/gcloud-java/blob/master/README.md#stackdriver-logging-alpha
-    
+
     ConsoleAppender appender = new ConsoleAppender(new SimpleLayout(), SYSTEM_OUT);
     logger.addAppender(appender);
   }
@@ -93,6 +97,17 @@ public void shutdown() throws InterruptedException {
     channel.shutdown().awaitTermination(5, TimeUnit.SECONDS);
   }
 
+  static ManagedChannel createChannel(String host, int port) throws IOException {
+    GoogleCredentials creds = GoogleCredentials.getApplicationDefault();
+    creds = creds.createScoped(OAUTH2_SCOPES);
+    ManagedChannel channel =
+        ManagedChannelBuilder.forAddress(host, port)
+            .intercept(new ClientAuthInterceptor(creds, Executors.newSingleThreadExecutor()))
+            .build();
+
+    return channel;
+  }
+
   /** Send streaming recognize requests to server. */
   public void recognize() throws InterruptedException, IOException {
     final CountDownLatch finishLatch = new CountDownLatch(1);
@@ -242,7 +257,7 @@ public static void main(String[] args) throws Exception {
       System.exit(1);
     }
 
-    ManagedChannel channel = AsyncRecognizeClient.createChannel(host, port);
+    ManagedChannel channel = createChannel(host, port);
     StreamingRecognizeClient client = new StreamingRecognizeClient(channel, audioFile, sampling);
     try {
       client.recognize();
diff --git a/speech/grpc/src/main/java/com/examples/cloud/speech/SyncRecognizeClient.java b/speech/grpc/src/main/java/com/examples/cloud/speech/SyncRecognizeClient.java
index cf6208774da..9b8e68efb17 100644
--- a/speech/grpc/src/main/java/com/examples/cloud/speech/SyncRecognizeClient.java
+++ b/speech/grpc/src/main/java/com/examples/cloud/speech/SyncRecognizeClient.java
@@ -16,6 +16,7 @@
 
 package com.examples.cloud.speech;
 
+import com.google.auth.oauth2.GoogleCredentials;
 import com.google.cloud.speech.v1beta1.RecognitionAudio;
 import com.google.cloud.speech.v1beta1.RecognitionConfig;
 import com.google.cloud.speech.v1beta1.RecognitionConfig.AudioEncoding;
@@ -25,7 +26,9 @@
 import com.google.protobuf.TextFormat;
 
 import io.grpc.ManagedChannel;
+import io.grpc.ManagedChannelBuilder;
 import io.grpc.StatusRuntimeException;
+import io.grpc.auth.ClientAuthInterceptor;
 
 import org.apache.commons.cli.CommandLine;
 import org.apache.commons.cli.CommandLineParser;
@@ -38,6 +41,7 @@
 import java.net.URI;
 import java.util.Arrays;
 import java.util.List;
+import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -49,15 +53,15 @@ public class SyncRecognizeClient {
 
   private static final Logger logger = Logger.getLogger(SyncRecognizeClient.class.getName());
 
-  private static final List<String> OAUTH2_SCOPES =
-      Arrays.asList("https://www.googleapis.com/auth/cloud-platform");
-
   private final URI input;
   private final int samplingRate;
 
   private final ManagedChannel channel;
   private final SpeechGrpc.SpeechBlockingStub speechClient;
 
+  private static final List<String> OAUTH2_SCOPES =
+      Arrays.asList("https://www.googleapis.com/auth/cloud-platform");
+
   /**
    * Construct client connecting to Cloud Speech server at {@code host:port}.
    */
@@ -78,6 +82,17 @@ public void shutdown() throws InterruptedException {
     channel.shutdown().awaitTermination(5, TimeUnit.SECONDS);
   }
 
+  static ManagedChannel createChannel(String host, int port) throws IOException {
+    GoogleCredentials creds = GoogleCredentials.getApplicationDefault();
+    creds = creds.createScoped(OAUTH2_SCOPES);
+    ManagedChannel channel =
+        ManagedChannelBuilder.forAddress(host, port)
+            .intercept(new ClientAuthInterceptor(creds, Executors.newSingleThreadExecutor()))
+            .build();
+
+    return channel;
+  }
+
   /** Send a non-streaming-recognize request to server. */
   public void recognize() {
     RecognitionAudio audio;
@@ -179,7 +194,7 @@ public static void main(String[] args) throws Exception {
       System.exit(1);
     }
 
-    ManagedChannel channel = AsyncRecognizeClient.createChannel(host, port);
+    ManagedChannel channel = createChannel(host, port);
     SyncRecognizeClient client = new SyncRecognizeClient(channel, URI.create(audioFile), sampling);
     try {
       client.recognize();
diff --git a/speech/grpc/src/test/java/com/examples/cloud/speech/StreamingRecognizeClientTest.java b/speech/grpc/src/test/java/com/examples/cloud/speech/StreamingRecognizeClientTest.java
index c42e521ebff..773af36c707 100644
--- a/speech/grpc/src/test/java/com/examples/cloud/speech/StreamingRecognizeClientTest.java
+++ b/speech/grpc/src/test/java/com/examples/cloud/speech/StreamingRecognizeClientTest.java
@@ -64,9 +64,9 @@ public void test16KHzAudio() throws InterruptedException, IOException {
 
     String host = "speech.googleapis.com";
     int port = 443;
-    ManagedChannel channel = AsyncRecognizeClient.createChannel(host, port);
+    ManagedChannel channel = StreamingRecognizeClient.createChannel(host, port);
     StreamingRecognizeClient client = new StreamingRecognizeClient(channel, path.toString(), 16000);
-    
+
     client.recognize();
     assertThat(writer.toString()).contains("transcript: \"how old is the Brooklyn Bridge\"");
   }
@@ -78,7 +78,7 @@ public void test32KHzAudio() throws InterruptedException, IOException {
 
     String host = "speech.googleapis.com";
     int port = 443;
-    ManagedChannel channel = AsyncRecognizeClient.createChannel(host, port);
+    ManagedChannel channel = StreamingRecognizeClient.createChannel(host, port);
     StreamingRecognizeClient client = new StreamingRecognizeClient(channel, path.toString(), 32000);
 
     client.recognize();