 Other equipment choices contribute to the Edge's unique sound.His 1964 Vox AC30 "Top Boost" amplifier (housed in a 1970s cabinet) is favoured for its "sparkle" tone, and is the basis for his sound both in the studio and live.The Edge has also used plectrums manufactured by the German company Herdim that he turns sideways or upside down so the dimpled grip strums against the strings, resulting in a "rasping top end" to his guitar tone.