compensate for the lower fidelity and high-frequency distortion on the inner track. Each groove needed its own monophonic needle and cartridge on its own branch of the tonearm, and each needle was connected to a separate amplifier and speaker. This setup was intended to give a demonstration at a New York audio fair of Cook's cutter heads rather than to sell the record; but soon afterward, the demand for such recordings and the equipment to play them grew, and Cook Records began to produce such records commercially. Cook recorded a vast array of sounds, ranging from railroad sounds to thunderstorms. By 1953, Cook had a catalog of about 25 stereo records for sale to audiophiles. Magnetic tape recording The first stereo recordings using magnetic tape were made in Germany in the early 1940s using Magnetophon recorders. Around 300 recordings were made of various symphonies, most of which were seized by the Red Army at the end of World War II. The recordings were of relatively high fidelity, thanks to the discovery of AC bias. A 1944 recording of Anton Bruckner's Symphony No. 8 directed by Herbert von Karajan and the Orchester der Berliner Staatsoper and a 1944 or 1945 recording of Walter Gieseking playing Beethoven's Piano Concerto No. 5 (with flak fire audible in the background) are the only recordings still known to exist. In the US, stereo magnetic tape recording was demonstrated on standard 1/4-inch tape for the first time in 1952, using two sets of recording and playback heads, upside-down and offset from one another. A year later, Remington Records began recording a number of its sessions in stereo, including performances by Thor Johnson and the Cincinnati Symphony Orchestra. Later that same year, more experimental stereo recordings were conducted with Leopold Stokowski and a group of New York studio musicians at RCA Victor Studios in New York City. In February 1954, the label also recorded a performance of Berlioz' masterpiece The Damnation of Faust by the Boston Symphony Orchestra under the direction of Charles Munch, the success of which led to the practice of regularly recording sessions in stereo. Shortly afterward, RCA Victor recorded the last two NBC Radio broadcast concerts by famed conductor Arturo Toscanini and the NBC Symphony Orchestra, on stereophonic magnetic tape, however, they were never officially released, though they have long been available on pirated LPs and CDs. In the UK, Decca Records began