Power Supply: AC DC 6-15V<br> Op Chip: XR1075<br> Recommended voltage: AC DC 12V<br> Working current: 5mA<br> Tone Adjustment: Treble Bass<br> of high resolution sound enhancement processor xr1075<br> For listener, this is reason that " technology can restore true and beautiful sound of scene Treasure.<br> instructions<br> 1. Connect input end to 12V (AC or DC is OK), and connect audio input end to ,<br> The output end is connected with rear power amplifier board, and speaker is connected. (as shown in Figure 2 below)<br> 2. The volume, treble output and bass output can be adjusted; from left to right: the first knob is high<br> The second one is bass adjustment, and last one is volume adjustment. Clockwise rotation increases, counter clockwise rotation decreases volume and high and low sound effects.<br> 3. Turn red key to switch sound effect with one key.<br> Different batches may have slight differences in appearance, which not affect use<br> Colour:Red<br> Material:ABS<br> Package Contents:<br> 1 x Audio Preamplifier<br> Only above package content, other products are not included.<br> Note: Light reflection and different displays may cause color of item in picture a little different from real thing. The measurement allowed error is +/- 1-3cm.