diff --git a/lib/websocket/driver.rb b/lib/websocket/driver.rb
index 0c3f11d..8306157 100644
--- a/lib/websocket/driver.rb
+++ b/lib/websocket/driver.rb
@@ -33,13 +33,12 @@ module WebSocket
       end
     end
 
-    unless String.instance_methods.include?(:force_encoding)
-      require root + '/utf8_match'
-    end
-
     MAX_LENGTH = 0x3ffffff
     STATES     = [:connecting, :open, :closing, :closed]
 
+    BINARY  = 'ASCII-8BIT'
+    UNICODE = 'UTF-8'
+
     ConnectEvent = Struct.new(nil)
     OpenEvent    = Struct.new(nil)
     MessageEvent = Struct.new(:data)
@@ -94,13 +93,14 @@ module WebSocket
       return false unless @ready_state == 0
       response = handshake_response
       return false unless response
-      @socket.write(Driver.encode(response, :binary))
+      @socket.write(response)
       open unless @stage == -1
       true
     end
 
     def text(message)
-      frame(message)
+      message = message.encode(UNICODE) unless message.encoding.name == UNICODE
+      frame(message, :text)
     end
 
     def binary(message)
@@ -159,14 +159,15 @@ module WebSocket
       case string
         when Array then
           string = string.pack('C*')
-          encoding ||= :binary
+          encoding ||= BINARY
         when String then
-          encoding ||= :utf8
+          encoding ||= UNICODE
       end
-      encodings = {:utf8 => 'UTF-8', :binary => 'ASCII-8BIT'}
-      string.force_encoding(encodings[encoding]) if string.respond_to?(:force_encoding)
-      return nil if encoding == :utf8 and not valid_utf8?(string)
-      string
+      unless string.encoding.name == encoding
+        string = string.dup if string.frozen?
+        string.force_encoding(encoding)
+      end
+      string.valid_encoding? ? string : nil
     end
 
     def self.validate_options(options, valid_keys)
@@ -177,14 +178,6 @@ module WebSocket
       end
     end
 
-    def self.valid_utf8?(string)
-      if defined?(UTF8_MATCH)
-        UTF8_MATCH =~ string ? true : false
-      else
-        string.valid_encoding?
-      end
-    end
-
     def self.websocket?(env)
       connection = env['HTTP_CONNECTION'] || ''
       upgrade    = env['HTTP_UPGRADE']    || ''
diff --git a/lib/websocket/driver/client.rb b/lib/websocket/driver/client.rb
index d2c54b6..0a45534 100644
--- a/lib/websocket/driver/client.rb
+++ b/lib/websocket/driver/client.rb
@@ -53,7 +53,7 @@ module WebSocket
 
       def start
         return false unless @ready_state == -1
-        @socket.write(Driver.encode(handshake_request, :binary))
+        @socket.write(handshake_request)
         @ready_state = 0
         true
       end
diff --git a/lib/websocket/driver/draft75.rb b/lib/websocket/driver/draft75.rb
index 403fcbe..041b725 100644
--- a/lib/websocket/driver/draft75.rb
+++ b/lib/websocket/driver/draft75.rb
@@ -56,7 +56,7 @@ module WebSocket
             when 2 then
               if octet == 0xFF
                 @stage = 0
-                emit(:message, MessageEvent.new(Driver.encode(@buffer, :utf8)))
+                emit(:message, MessageEvent.new(Driver.encode(@buffer, UNICODE)))
               else
                 if @length
                   @skipped += 1
diff --git a/lib/websocket/driver/draft76.rb b/lib/websocket/driver/draft76.rb
index 3643b75..aa28c2c 100644
--- a/lib/websocket/driver/draft76.rb
+++ b/lib/websocket/driver/draft76.rb
@@ -8,7 +8,7 @@ module WebSocket
         super
         input  = @socket.env['rack.input']
         @stage = -1
-        @body  = Driver.encode(input ? input.read : '', :binary)
+        @body  = (input ? input.read : String.new('')).force_encoding(BINARY)
 
         @headers.clear
         @headers['Upgrade'] = 'WebSocket'
@@ -70,7 +70,7 @@ module WebSocket
 
       def send_handshake_body
         return unless signature = handshake_signature
-        @socket.write(Driver.encode(signature, :binary))
+        @socket.write(signature)
         @stage = 0
         open
         parse(@body[BODY_SIZE..-1]) if @body.bytesize > BODY_SIZE
diff --git a/lib/websocket/driver/hybi.rb b/lib/websocket/driver/hybi.rb
index 6c47219..36d1905 100644
--- a/lib/websocket/driver/hybi.rb
+++ b/lib/websocket/driver/hybi.rb
@@ -129,10 +129,6 @@ module WebSocket
         end
       end
 
-      def text(message)
-        frame(message, :text)
-      end
-
       def binary(message)
         frame(message, :binary)
       end
@@ -356,7 +352,7 @@ module WebSocket
 
           when OPCODES[:close] then
             code   = (bytesize >= 2) ? payload.unpack(PACK_FORMATS[2]).first : nil
-            reason = (bytesize > 2)  ? Driver.encode(bytes[2..-1] || [], :utf8) : nil
+            reason = (bytesize > 2)  ? Driver.encode(bytes[2..-1] || [], UNICODE) : nil
 
             unless (bytesize == 0) or
                    (code && code >= MIN_RESERVED_ERROR && code <= MAX_RESERVED_ERROR) or
@@ -374,7 +370,7 @@ module WebSocket
             frame(payload, :pong)
 
           when OPCODES[:pong] then
-            message = Driver.encode(payload, :utf8)
+            message = Driver.encode(payload, UNICODE)
             callback = @ping_callbacks[message]
             @ping_callbacks.delete(message)
             callback.call if callback
@@ -391,7 +387,7 @@ module WebSocket
 
         case message.opcode
           when OPCODES[:text] then
-            payload = Driver.encode(payload, :utf8)
+            payload = Driver.encode(payload, UNICODE)
           when OPCODES[:binary]
             payload = payload.bytes.to_a
         end
diff --git a/lib/websocket/driver/hybi/message.rb b/lib/websocket/driver/hybi/message.rb
index 06fcf94..7a62f9e 100644
--- a/lib/websocket/driver/hybi/message.rb
+++ b/lib/websocket/driver/hybi/message.rb
@@ -14,7 +14,7 @@ module WebSocket
           @rsv2   = false
           @rsv3   = false
           @opcode = nil
-          @data   = Driver.encode('', :binary)
+          @data   = String.new('').force_encoding(BINARY)
         end
 
         def <<(frame)
diff --git a/lib/websocket/driver/proxy.rb b/lib/websocket/driver/proxy.rb
index 6434782..e4891e3 100644
--- a/lib/websocket/driver/proxy.rb
+++ b/lib/websocket/driver/proxy.rb
@@ -44,7 +44,7 @@ module WebSocket
         start   = "CONNECT #{@origin.host}:#{port} HTTP/1.1"
         headers = [start, @headers.to_s, '']
 
-        @socket.write(Driver.encode(headers.join("\r\n"), :binary))
+        @socket.write(headers.join("\r\n"))
         true
       end
 
diff --git a/lib/websocket/driver/server.rb b/lib/websocket/driver/server.rb
index 1cbaf23..f13fde9 100644
--- a/lib/websocket/driver/server.rb
+++ b/lib/websocket/driver/server.rb
@@ -58,7 +58,7 @@ module WebSocket
       end
 
       def write(buffer)
-        @socket.write(Driver.encode(buffer, :binary))
+        @socket.write(buffer)
       end
 
     private
diff --git a/lib/websocket/driver/stream_reader.rb b/lib/websocket/driver/stream_reader.rb
index 90e7172..0ce8683 100644
--- a/lib/websocket/driver/stream_reader.rb
+++ b/lib/websocket/driver/stream_reader.rb
@@ -6,13 +6,13 @@ module WebSocket
       MINIMUM_AUTOMATIC_PRUNE_OFFSET = 128
 
       def initialize
-        @buffer = Driver.encode('', :binary)
+        @buffer = String.new('').force_encoding(BINARY)
         @offset = 0
       end
 
       def put(chunk)
         return unless chunk and chunk.bytesize > 0
-        @buffer << Driver.encode(chunk, :binary)
+        @buffer << chunk.force_encoding(BINARY)
       end
 
       # Read bytes from the data:
@@ -42,7 +42,7 @@ module WebSocket
         buffer_size = @buffer.bytesize
 
         if @offset > buffer_size
-          @buffer = Driver.encode('', :binary)
+          @buffer = String.new('').force_encoding(BINARY)
         else
           @buffer = @buffer.byteslice(@offset, buffer_size - @offset)
         end
diff --git a/lib/websocket/driver/utf8_match.rb b/lib/websocket/driver/utf8_match.rb
deleted file mode 100644
index b0fc7af..0000000
--- a/lib/websocket/driver/utf8_match.rb
+++ /dev/null
@@ -1,6 +0,0 @@
-module WebSocket
-  class Driver
-    # http://www.w3.org/International/questions/qa-forms-utf-8.en.php
-    UTF8_MATCH = /^([\x00-\x7F]|[\xC2-\xDF][\x80-\xBF]|\xE0[\xA0-\xBF][\x80-\xBF]|[\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}|\xED[\x80-\x9F][\x80-\xBF]|\xF0[\x90-\xBF][\x80-\xBF]{2}|[\xF1-\xF3][\x80-\xBF]{3}|\xF4[\x80-\x8F][\x80-\xBF]{2})*$/
-  end
-end
diff --git a/spec/websocket/driver/draft75_spec.rb b/spec/websocket/driver/draft75_spec.rb
index 1ab8f00..4cbd88d 100644
--- a/spec/websocket/driver/draft75_spec.rb
+++ b/spec/websocket/driver/draft75_spec.rb
@@ -90,7 +90,7 @@ describe WebSocket::Driver::Draft75 do
             "WebSocket-Origin: http://www.example.com\r\n" +
             "WebSocket-Location: ws://www.example.com/socket\r\n" +
             "\r\n")
-        expect(socket).to receive(:write).with(WebSocket::Driver.encode "\x00Hi\xFF", :binary)
+        expect(socket).to receive(:write).with(WebSocket::Driver.encode "\x00Hi\xFF", WebSocket::Driver::BINARY)
 
         driver.frame("Hi")
         driver.start
diff --git a/spec/websocket/driver/draft76_spec.rb b/spec/websocket/driver/draft76_spec.rb
index 39aa1e7..7c3a8b1 100644
--- a/spec/websocket/driver/draft76_spec.rb
+++ b/spec/websocket/driver/draft76_spec.rb
@@ -137,7 +137,7 @@ describe WebSocket::Driver::Draft76 do
             "Sec-WebSocket-Location: ws://www.example.com/socket\r\n" +
             "\r\n")
         expect(socket).to receive(:write).with(response)
-        expect(socket).to receive(:write).with(WebSocket::Driver.encode "\x00Hi\xFF", :binary)
+        expect(socket).to receive(:write).with(WebSocket::Driver.encode "\x00Hi\xFF", WebSocket::Driver::BINARY)
 
         driver.frame("Hi")
         driver.start
@@ -191,7 +191,7 @@ describe WebSocket::Driver::Draft76 do
 
           it "sends any frames queued before the handshake was complete" do
             expect(socket).to receive(:write).with(response)
-            expect(socket).to receive(:write).with(WebSocket::Driver.encode "\x00hello\xFF", :binary)
+            expect(socket).to receive(:write).with(WebSocket::Driver.encode "\x00hello\xFF", WebSocket::Driver::BINARY)
             driver.frame("hello")
             driver.parse(body)
             expect(@bytes).to eq [0, 104, 101, 108, 108, 111, 255]