The Hill Audio RPQ-2150 is a 2×15 band stereo graphic EQ and as such the tool of choice to adapt a sound system to a given location or listening requirement. With every sound system offering a different tonal balance and every room providing different acoustic properties, certain frequencies might need boosting or attenuation to balance the sound, and this is what this unit does in perfection. In addition to the 2×15 frequency bands which allow adjustment in either a ±6 dB or ±12 dB range, a 25Hz low-cut filter allows removal of very low-frequency content such as rumble and hum to preserve precious amplification headroom and keep the bottom end clear and punchy. As extra features, a basic active crossover is built-in which allows the direct connection of a subwoofer system, and the PeakID system visually warns of energy accumulations in certain frequency bands which indicate the danger of feedback. Unlike digital EQs, the RPQ-2150 works on a full +20dB maximum level range and hence offers superior headroom. Its usefulness makes this unit is an invaluable improvement to any professional sound system.