In any home audio system, there are a variety of stationary devices to which the amplifier is connected. The cables connecting your CD/DVD player or turntable to the amplifier are never a problem because you rarely have to move any of these components around. However, having to physically connect a computer to an amplifier in order to play audio over your sound system's speakers can pose difficulties. Using a Bluetooth audio receiver with your computer's Bluetooth capabilities allows you to easily stream music to your speakers and still be able to move your computer almost anywhere.
Shop around for a Bluetooth audio receiver. This will be the module in which to connect your amplifier to stream music to your speakers. Some models are sold with an external transmitter unit which plug into your computer's headphone port. You need this if your computer lacks a built-in Bluetooth chip, or if you plan to use your computer to stream music when more than 30 feet from the receiver.
Connect the receiver to your audio system. The receiver should feature a headphone port into which you can plug the 3.5mm jack, with the other end of the cable being used as an input to your amplifier. Some receiver models may have RCA ports and instead require an RCA-to-RCA cable. If your speakers are designed for computer use and you don't have an external receiver, simply plug their headphone jack into the receiver's port.
Plug in the external transmitter if your model includes one. If not, start streaming the audio over your computer's Bluetooth as per the instructions included with your receiver.