Alpine is one of the leading manufacturers of car audio and automotive navigation systems. It is an esteemed name in the business of high quality, high price in-car audio systems, which are popularly known as head units. This company is a subsidiary of Alps Electric Co., and is based in Iwaki-City, Fukushima Prefecture, Japan. It provides a diverse range of products such as amplifiers, speakers, subwoofers, and signal processing equipment. Alpine has manufactured various innovative products including the first automotive navigation system, first in-car computerized equalizer, first in-dash 3-CD changer, etc.

The Alpine 3331 Band Graphic Equalizer is one of the innovative products from the Alpine range of audio products that offers excellent system control in a compact package with 11 independently adjustable frequency bands. The Alpine 3331 supports the center frequencies at 31.5 Hz, 63 Hz, 125 Hz, 190 Hz, 250 Hz, 500 Hz, 1 KHz, 2.2 KHz, 4.5 KHz, 9 KHz. In addition, the equalizer has a 18 KHz to 30 KHz frequency response. The 3331 is boasts a high-pass and low-pass crossovers with 18 db/oct and is adjustable between crossover frequency of 50 Hz and 120 Hz. It has built-in three sets of preamp outputs, subwoofer level control, subwoofer phase switch, and an easy input level indicator. The integrated BBE sound processor offers crystal clear sound and enhances the music by manipulating phase relationships and pumping up bass response.

The Alpine 3331 also features additional controls such as fader control, separate sub-control with crossover and amplifier line driver. It boasts of a cool looks that will complement any head unit.