All VXi amplifiers feature a convenient Signal Sense and DC Offset method for turn-on management. This allows for VXi amplifiers to turn on and off without the need for a switched 12 volt source of power. This can be useful when a vehicle does not have an easily accessible switched or accessory power source. Since there are no external settings on the amplifiers we must power the amplifier up to connect with the TüN™ software for the initial set up. You can do this by taking a direct lead wire and connect it to the positive battery terminal and run it to the remote terminal of the amplifier or by jumping a wire from the main power input terminal of the amplifier over to the remote input terminal. This will turn on the amplifier temporarily while we set it up for signal sense or DC offset. Take care not to short the wire out at the amplifier terminal or make contact with any metal in the vehicle when doing so. Now that the VXi amplifier is turned on we can get set up for either the signal sense or DC offset turn on mode. (Note: Signal must be connected to input 1 of any VXi amplifier since the Signal Sense function is tied to this input)
TüN™ (PC & Mac)
1. In the SETUP tab, click the “>>” icon to the right of the INPUTS label to expand a drawer showing Input Levels on the left side and the Turn-On Mode selection on the right.
2. Click on the appropriate box to check mark either signal sense or DC offset, as needed.
3. Click the transfer icon in the left margin of the software to transfer the change to the amplifier.
TüN™ Mobile
1. On the SETUP tab within TüN Mobile, click on the 
next to the INPUTS label to open a drawer showing Input Level and other settings.
2. Click on the appropriate box to check mark either signal sense or DC offset.
3. Now click the transfer icon in the left margin of the App to transfer this change over to the amplifier.
Turn-On Management in TüN™ Mobile
TüN™ Express
1. On the Amp Setup page you can choose Remote, DC Offset, or Signal as the desired Turn On Mode.
2. Once the selection is made, click on the in the upper left margin of TüN™ Express and select "Transfer Project to VXi" to transfer this change over to the amplifier.
Now that you have transferred the change of signal sense or DC offset over to the amplifier you can disconnect the temporary direct power lead from the remote terminal of the amplifier and the battery. When the amplifier power is cycled off and on again, the amplifier should power on automatically when audio signal is detected or if DC current is detected through high level signal connection.