The Porsche 911 cars have a variety of amplified audio options, depending on what is in the car affects what fitting parts are required when installing a new stereo.
The information below describes the different original audio equipment that is in these cars, this information is needed to make sure the correct parts are used when fitting a new stereo.
2004 - 2009 models
Unlike the Boxster and Cayman, the 911 cars were all fitted with the high end PCM2 and 2.1 head units. These units have ISO connectors at the rear.
There are two types of audio systems in 911s, ASK amplifier, known as the Sound Package Plus system (SPP) and Bose premium amplifier. The ASK amplifier has audio supplied to it from the head unit from the normal speaker ISO connector, a +12v feed turns on the amplifier. The Bose amplifier has a fibre optic connection from the head unit.
The image below shows the connection at the radio for cars with the ASK and Bose amplifiers.
The left image is a car with an ASK amplifier, all 4 channels are populated in the speaker ISO and there is an amplifier turn on wire (thin black with red stripe) in the power ISO connector. The image to the right has a Bose amplifier, there are no speaker wires present, the audio is sent to the amplifier via the orange fibre optic cables. Note: the car with the ASK amplifier also has fibre optic cables, these connect the head unit to the CD changer, they do not carry audio to the ASK amplifier.
The type of amplifier can be identified by looking at the wiring behind the radio, as per above images, or by looking at the door speakers. Cars with Bose amplifiers will have Bose branding on the speaker grills. See the image below.
2009 - 2012 models
Like the earlier version 911, the 2009 to 2012 models are only fitted with the high end PCM 3 head units, the CDR30 unit is not an option like the Boxster and Cayman. The PCM3 units have a quadlock connector at the rear instead of ISO connectors like the earlier model. They have the same options of ASK and Bose amplified audio systems.
The type of amp can be identified in the same way as the earlier model, either by the Bose branding on the speakers grills or by looking at the connectors at the back of the radio.
Below shows a car with ASK amplifier (image 1) and a car with Bose amplifier (image 2). Note how the car with an ASK amplifier has speaker wires present in the quadlock connector and the car with Bose does not.