If you didn't want to spend a lot of money on this upgrade.This unit can add Bluetooth to your older, pre-Bluetooth/WiFi surround receiver, so you could play songs from your smartphone.

The Esinkin bluetooth receiver contains two methods to supply power: a small AC to DC Power Adapter, and an adequate length of cable for USB power. It doesn't have built-in battery, you need to keep the device powered on to start it

The method of connection to your receiver, is accomplished by a supplied 3.5 plug to RCA Right and Left (Red and White) cable. Of course, the 3.5 plug goes into the rear of the unit and the RCA jacks plug into your receiver. As an alternative, there are two RCA jacks on the rear of the unit, which you can use your own adapter cable to suite your situation.

The operation of the unit is pretty straightforward. When you first plugged it in, it was already on, which is indicated by a small, white light at the bottom front. Push the top button once, and the unit goes into pairing mode. Then your smartphone will paired very quickly, and once paired the light on the unit turned blue. To turn the unit off, you simply hold the button down for 3 seconds, then the light turns white and goes out. Same process to turn it on, which resulted in an auto-connect back to your phone. This bluetooth receiver will connect to as many as you want but can only be connected to one at a time. Before connecting a new device, you need to disconnect the previously connected device so that the new device can be successfully connected.

In fact, you can control the volume convenient. First, you can control the volume from your smartphone, then adjust the level on your receiver to where I want it (kind of loud). From there you can turn it down in an instant, if need be. Remember also to adjust your music playback settings, enhancements or quality including your equalizer and surround sound to get the best clarity and either go up higher on your levels of output sound or you may need to bring it down if your music or sound is distorted.

If i get multiple adapters can i change the bluetooth Search term:name so i know which one i'm connecting to which device? Of course. When paired, they all have the same name, but their internal key pairs will differ, so the device you pair them with (phone, computer) can tell them apart. You'll want to rename them on the device. Renaming it on one device will not change the adapter's name if you pair it with another. You can changed how the phone recognize them after they connected the first time. Ie. will look for "Esinkin BT Adapter". When the phone connects you can then change the name in that phone to "William" or anything, but if any new phone comes on it will show "Esinkin BT Adapter".