The Warm Audio WA-MPX is an authentic reproduction of one of the most revered microphone tube preamps that pioneered the birth of rock 'n' roll & radio-ready hits. During the golden-era of tape recording, this style of vintage tube preamp became the signature sound in the signal chain of hit recordings including Elvis Presley, Kurt Cobain, Les Paul and Bing Crosby - and is a sound that is still pursued by today's biggest artists. With premium components, true-to-original circuit design and tape saturation control, the WA-MPX authentically reproduces all the analog tone of the original to bring vintage warmth & color to your sound.