[. . . ] - Make sure you do not damage vehicle components when drilling any holes. - The cross sections of the positive and negative cables must not be less than 2. [. . . ] - The cross sections of the positive and negative cables must not be less than 2. - Incorrect installation may cause interference with electronic vehicle systems or your car radio. The final stage must be installed professionally for reasons of safety. The mounting surface must be suitable for the screws provided, and must provide firm support (see Fig. Fit a fuse in the amplifier power line no more than 30 cm from the vehicle battery, in order to protect the battery in the event of a short-circuit between it and the power amplifier. Next, using the Crossover control 3, select a crossover frequency that produces a well-balanced bass sound. You may have to alternate between finely tuning Gain control 1 and Crossover control 3 to optimise the sound. Booming bass with an exaggerated volume can be achieved by setting the crossover to a low frequency. The Phase control should be adjusted so that the bass blends as best as possible into the overall sound and is not heard as a distinct source. Check your tuning of the VRB 8A with the bass control fully turned up and, if necessary, with the loudness turned on. [. . . ] The Phase control should be adjusted so that the bass blends as best as possible into the overall sound and is not heard as a distinct source. Check your tuning of the VRB 8A with the bass control fully turned up and, if necessary, with the loudness turned on. [. . . ]